Kalyani Putty - Academia.edu (original) (raw)

Papers by Kalyani Putty

Research paper thumbnail of Development and evaluation of NS1 protein based i-ELISA for serodiagnosis of Bluetongue disease

Development and evaluation of NS1 protein based i-ELISA for serodiagnosis of Bluetongue disease

Indian Journal of Small Ruminants, 2022

Research paper thumbnail of Comparative Neuropathology of Major Indian Bluetongue Virus Serotypes in a Neonatal BALB/c Mouse Model

Journal of Comparative Pathology, 2018

Bluetongue virus (BTV) is neurotropic in nature, especially in ruminant fetuses and in-utero infe... more Bluetongue virus (BTV) is neurotropic in nature, especially in ruminant fetuses and in-utero infection results in abortion and congenital brain malformations. The aim of the present study was to compare the neuropathogenicity of major Indian BTV serotypes 1, 2, 10, 16 and 23 by gross and histopathological lesions and virus distribution in experimentally infected neonatal BALB/c mice. Each BTV serotype (20 ml of inoculum containing 1 Â 10 5 tissue culture infectious dose [TCID] 50 /ml of virus) was inoculated intracerebrally into 3-day-old mice, while a control group was inoculated with mock-infected cell culture medium. Infection with BTV serotypes 1, 2 and 23 led to 65e70% mortality at 7e9 days post infection (dpi) and caused severe necrotizing encephalitis with neurodegenerative changes in neurons, swelling and proliferation of vascular endothelial cells in the cerebral cortex, cerebellum, midbrain and brainstem. In contrast, infection with BTV serotypes 10 and 16 led to 25e30% mortality at 9e11 dpi and caused mild neuropathological lesions. BTV antigen was detected by immunohistochemistry, direct fluorescence antibody technique and confocal microscopy in the cytoplasm of neuronal cells of the hippocampus, grey matter of the cerebral cortex and vascular endothelial cells in the midbrain and brainstem of BTV-1,-2,-10,-16 and-23 infected groups from 3 to 20 dpi. BTV nucleic acid was detected in the infected brain tissues from as early as 24 h up to 20 dpi by VP7 gene segment-based onestep reverse transcriptase polymerase chain reaction. This study of the relative neurovirulence of BTV serotypes is likely to help design suitable vaccination and control strategies for the disease.

Research paper thumbnail of Epidemiology of Bluetongue in India

Epidemiology of Bluetongue in India

Transboundary and Emerging Diseases, 2014

Bluetongue (BT) is an insectborne endemic disease in India. Although infections are observed in d... more Bluetongue (BT) is an insectborne endemic disease in India. Although infections are observed in domestic and wild ruminants, the clinical disease and mortality are observed only in sheep, especially in the southern states of the country. The difference in disease patterns in different parts of the country could be due to varied climatic conditions, sheep population density and susceptibility of the sheep breeds to BT. Over the five decades after the first report of BT in 1964, most of the known serotypes of bluetongue virus (BTV) have been reported from India either by virus isolation or by detection of serotype-specific antibodies. There have been no structured longitudinal studies to identify the circulating serotypes throughout the country. At least ten serotypes were isolated between 1967 and 2000 (BTV-1-4, 6, 9, 16-18, 23). Since 2001, the All-India Network Programme on Bluetongue and other laboratories have isolated eight different serotypes (BTV-1-3, 9, 10, 12, 16, 21). Genetic analysis of these viruses has revealed that some of them vary substantially from reference viruses, and some show high sequence identity with modified live virus vaccines used in different parts of the world. These observations have highlighted the need to develop diagnostic capabilities, especially as BT outbreaks are still declared based on clinical signs. Although virus isolation and serotyping are the gold standards, rapid methods based on the detection of viral nucleic acid may be more suitable for India. The epidemiological investigations also have implications for vaccine design. Although only a handful serotypes may be involved in causing outbreaks every year, the combination of serotypes may change from year to year. For effective control of BT in India, it may be pertinent to introduce sentinel and vector traps systems for identification of the circulating serotypes and to evaluate herd immunity against different serotypes, so that relevant strains can be included in vaccine formulations.

Research paper thumbnail of Quantitative and qualitative assessment of serum- and inflammatory mediator-induced migration of carp (Cyprinus carpio) head kidney neutrophils in vitro

Fish & Shellfish Immunology, 2006

A quantitative transmigration system, permitting the harvest of transmigrated cells for further a... more A quantitative transmigration system, permitting the harvest of transmigrated cells for further analysis, was used to study carp head kidney (HK) granulocyte migration in vitro. Pooled carp serum and leukotriene B4 (LTB-4), but not recombinant human C-X-C chemokine ligand 8 (rhCXCL8), recombinant human complement component 5a (rhC5a) or N-formyl-methionyl-leucyl-phenylalanine (FMLP) induced strong migration (up to 70%) of carp HK granulocytes. The transmigrated cells were viable (!96%) and uniform (purity !97%). After serum-as well as LTB-4-induced transmigration granulocytes produced the same amounts of reactive oxygen species (ROS) as non-migrated cells in HK cell suspension. Their morphology, staining characteristics and flow cytometric scatter characteristics, plus their ability to produce ROS characterised the transmigrated granulocytes as neutrophils. The quantitative transmigration system described here could also serve as an excellent tool for the selective attraction and isolation of highly purified carp neutrophils from HK cell suspensions.

Research paper thumbnail of A new multiplex RT-PCR assay for serotyping of bluetongue virus

IJBT Vol.19(3) [July 2020], Jul 1, 2020

Among all viral diseases affecting small ruminants, bluetongue is the one that affects adversely ... more Among all viral diseases affecting small ruminants, bluetongue is the one that affects adversely to an alarming extent. The current available diagnosis/serotyping of bluetongue virus (BTV) is time consuming, costly, and requires to screen individually for each of the 29 distinct serotypes. The present study was conducted with the objective of developing a multiplex reverse transcription PCR (mRT-PCR) assay for serotyping of BTV, especially for serotypes BTV-1, 2, 9, 12, 16, 21 and 23 predominantly circulating in India. The type specific primers for the selected BTV serotypes were designed targeting the serotype specific segment-2 region of BTV based on the reference serotype sequences of Indian isolates available in GenBank. The mRT-PCR was conducted in two groups-group A for BTV-1, 9, 12, 21 and group B for BTV-2, 16 and 23. A panel of 25 BT suspected clinical samples were typed by mRT-PCR. The results were further validated by the gold standard serum neutralization test (SNT). A seroprevalence of 60% for BTV-2, 10% for BTV-9, 15% for BTV-1, 10% for BTV-16 and 5% for BTV-23 were observed. Further, we noticed that there was a mixed serotype infection in 10% of BTV positive samples. In conclusion, we report the development of a novel mRT-PCR assay for a rapid and costeffective nucleic acid based serotyping of BTV having the specificity same as SNT.

Research paper thumbnail of Comparative evaluation of the effect of L-Arginine and L-Homoarginine supplementation on reproductive physiology in ewes

Comparative evaluation of the effect of L-Arginine and L-Homoarginine supplementation on reproductive physiology in ewes

Research in Veterinary Science

Research paper thumbnail of Comparative evaluation of the effect of L-Arginine and L-Homoarginine supplementation on reproductive physiology in ewes

Comparative evaluation of the effect of L-Arginine and L-Homoarginine supplementation on reproductive physiology in ewes

Research in Veterinary Science

Research paper thumbnail of First report of canine bufavirus in India

Archives of Virology, 2022

Canine bufavirus (CBuV), a novel protoparvovirus of dogs that is associated with enteric and resp... more Canine bufavirus (CBuV), a novel protoparvovirus of dogs that is associated with enteric and respiratory symptoms, has been reported only in Italy and China. The enteric prevalence of CBuV in India was investigated, and the nearly complete genome sequence (4292 bp) was amplified and reconstructed for one strain. A nucleotide sequence alignment indicated 93.42-98.81% identity to the other available CBuV sequences and 70.88-73.39% and 54.4-54.8% identity to human bufavirus and canine parvovirus 2 (CPV-2), respectively. The current strain is most closely related to Chinese CBuV strains, which together form an Asian lineage. This first report of the prevalence of CBuV in India emphasizes the need for further epidemiological surveillance.

Research paper thumbnail of Antagonistic effect of ursolic acid on Staphylococcal biofilms

Veterinary World, 2018

Aim: The present study was carried out to study the effect of ursolic acid (UA) as a potential an... more Aim: The present study was carried out to study the effect of ursolic acid (UA) as a potential anti-biofilm agent in dispersing the biofilm generated by Staphylococcus aureus isolated from milk samples of crossbred dairy cows on the day of drying. Further, in the S. aureus isolates, the presence of intracellular adherence gene locus involved in biofilm production (icaD) was investigated. Materials and Methods: A total of 50 S. aureus strains were isolated over a period of 3 months from 200 milk samples collected from crossbred dairy cows on the day of drying. These isolates were subjected for biofilm detection by Congo red agar (CRA), microtiter plate assay (MTP), and polymerase chain reaction specific for icaD gene. The antagonistic effect of biofilm formation by UA was studied using different concentrations (30 µg/ml and 60 µg/ml) of UA and compared with the control group. Results: Among the 50 S. aureus subjected for biofilm detection, 34 and 40 isolates were detected as biofilm agents by CRA and MTP methods, respectively. The in vitro studies on the effect of UA in inhibiting biofilm formation by S. aureus using MTP assay showed 71.5% and 48.6% inhibition at UA concentrations of 60 µg/ml and 30 µg/ml, respectively, with a significant difference (p<0.05) between the treated and untreated isolates, which was further evident by scanning electron microscopy. Interestingly, the isolates that were tested to be resistant through Antibiotic Sensitivity Test to commonly used antibiotics were found to be sensitive to all the tested antibiotics following UA treatment at both the tested concentrations. Furthermore, molecular detection of icaD gene for biofilm detection revealed that all the isolates that were positive by MTP had icaD gene. Conclusion: Increased incidence of biofilm agents in dairy infections must be considered as an alarming situation. UA treatment significantly enhanced the sensitivity of the microbial pathogens to commonly used antibiotics. Hence, attention must be paid toward implementation of new strategies such as therapeutic regimes with a combination of antibiotic and anti-biofilm agents for effective treatment of infections in dairy farms.

Research paper thumbnail of Type-specific seroprevalence of bluetongue in India during 2018 and 2019

Background and Aim: Bluetongue (BT) is a major disease of sheep and goats and is endemic to India... more Background and Aim: Bluetongue (BT) is a major disease of sheep and goats and is endemic to India. It is known to cause significant economic losses to the sheep industry. The current study aimed to determine the type-specific seroprevalence of BT in sheep population of India during 2018-2019. Materials and Methods: Blood samples (n=405) were collected from 6 months to 1 year old sheep from six districts (Nalgonda, Karimnagar, Khammam, Mahabubnagar, Warangal, and Ranga Reddy) of Telangana state, India. Group- and type-specific seroprevalence (against BT virus [BTV] serotypes BTV-1, 2, 4, 5, 9, 10, 12, 16, 21, 23, and 24) was studied by competitive enzyme-linked immunosorbent assay and serum neutralization test, respectively. Results: Results showed an overall seroprevalence of 14.81% (n=60) with the highest seroprevalence of 50% in Khammam district. Seroprevalence of BTV-1, 2, 4, 5, 9, 10, 12, 16, 21, 23, and 24 was noted as 16.66%, 11.66%, 31.66%, 11.66%, 05%, 6.66%, 16.66%, 8.33%, ...

Research paper thumbnail of Infection kinetics and antibody responses in Deccani sheep during experimental infection and superinfection with bluetongue virus serotypes 4 and 16

Veterinary World, 2019

Aim: The current study was designed to understand the infection kinetics and antibody responses o... more Aim: The current study was designed to understand the infection kinetics and antibody responses of major circulating serotypes of bluetongue virus (BTV) in India, i.e., BTV-4 and BTV-16 through experimental infection and superinfection of Deccani sheep, a popular breed of sheep found in the southern states of India. Materials and Methods: Experimental infection with 106 TCID50/ml BTV-4 was followed by superinfection with BTV-16 and vice versa. Along with observing for clinical signs and immunological responses in the experimentally infected sheep, the effect of infection of one specific serotype on the outcome of superinfection with a different serotype was also studied. Results: Certain interesting findings have been made in the course of experimental infection, such as prominent signs of infection in BTV-4 infection, mild or no clinical signs in BTV-16-infected and superinfected animals, and non-seroconversion of one of the BTV-16-superinfected animals. In addition, BTV was isolat...

Research paper thumbnail of Standardization and application of real-time polymerase chain reaction for rapid detection of bluetongue virus

Veterinary world, 2018

The present study was designed to standardize real-time polymerase chain reaction (PCR) for detec... more The present study was designed to standardize real-time polymerase chain reaction (PCR) for detecting the bluetongue virus from blood samples of sheep collected during outbreaks of bluetongue disease in the year 2014 in Andhra Pradesh and Telangana states of India. A 10-fold serial dilution of Plasmid PUC59 with bluetongue virus (BTV) NS3 insert was used to plot the standard curve. BHK-21 and KC cells were used for propagation of virus BTV-9 at a TCID50/ml of 10 ml and RNA was isolated by the Trizol method. Both reverse transcription-PCR and real-time PCR using TaqMan probe were carried out with RNA extracted from virus-spiked culture medium and blood to compare the sensitivity by means of finding out the limit of detection (LoD). The results were verified by inoculating the detected and undetected dilutions onto cell cultures with further cytological (cytopathic effect) and molecular confirmation (by BTV-NS1 group-specific PCR). The standardized technique was then applied to field ...

Research paper thumbnail of Dual Infection with Bluetongue Virus Serotypes and First-Time Isolation of Serotype 5 in India

Transboundary and emerging diseases, Jan 21, 2016

Bluetongue is endemic in India and has been reported from most Indian states. Of late, the clinic... more Bluetongue is endemic in India and has been reported from most Indian states. Of late, the clinical disease is most frequently seen in the states of Andhra Pradesh, Telangana (erstwhile Andhra Pradesh state), Tamil Nadu and Karnataka. Our analysis of diagnostic samples from bluetongue outbreaks during 2010-2011 from the state of Karnataka identified bluetongue virus (BTV) serotype 5 (BTV-5) for the first time in India. One of the diagnostic samples (CH1) and subsequent virus isolate (IND2010/02) contained both BTV-2 and BTV-5. Segment 2 (seg-2) sequence data (400 bp: nucleotides 2538-2921) for IND2010/02-BTV5, showed 94.3% nucleotide identity to BTV-5 from South Africa (Accession no. AJ585126), confirming the virus serotype and also indicating that Seg-2 was derived from a Western topotype, which is in contrast to serotype 2, that belongs to an Eastern topotype. BTV-5 has been recently reported from Africa, China, French islands and the Americas. Although the exact source of the Ind...

Research paper thumbnail of Role of eukaryotic Sel-1 like repeat containing genes in Helicobacter pylori evolution and pathogenesis

This study ~hp468: 594-617 189bp AmplifIcation of fragment of hepC for performing RT-PCR This stu... more This study ~hp468: 594-617 189bp AmplifIcation of fragment of hepC for performing RT-PCR This study ureA: 695•771 This study meA" 501-529 271bp AmplifICation of fragment of ureA for performing RT-PCR This study recA: 23-4 This study recA: 180-209 206bp AmolifICation of fragment of recA for performing RT-PCR This study GAPDH" 369-389 This study

Research paper thumbnail of Vaccination with Embryonic Stem Cells Protects against Lung Cancer: Is a Broad-Spectrum Prophylactic Vaccine against Cancer Possible?

PLoS ONE, 2012

The antigenic similarity between tumors and embryos has been appreciated for many years and refle... more The antigenic similarity between tumors and embryos has been appreciated for many years and reflects the expression of embryonic gene products by cancer cells and/or cancer-initiating stem cells. Taking advantage of this similarity, we have tested a prophylactic lung cancer vaccine composed of allogeneic murine embryonic stem cells (ESC). Naïve C57BL/6 mice were vaccinated with ESC along with a source of granulocyte macrophage-colony stimulating factor (GM-CSF) in order to provide immunostimulatory adjuvant activity. Vaccinated mice were protected against subsequent challenge with implantable Lewis lung carcinoma (LLC). ESC-induced anti-tumor immunity was not due to a non-specific ''allo-response'' as vaccination with allogeneic murine embryonic fibroblasts did not protect against tumor outgrowth. Vaccine efficacy was associated with robust tumor-reactive primary and memory CD8 + T effector responses, Th1 cytokine response, higher intratumoral CD8 + T effector/CD4 + CD25 + Foxp3 + T regulatory cell ratio, and reduced myeloid derived suppressor cells in the spleen. Prevention of tumorigenesis was found to require a CD8-mediated cytotoxic T lymphocyte (CTL) response because in vivo depletion of CD8 + T lymphocytes completely abrogated the protective effect of vaccination. Importantly, this vaccination strategy also suppressed the development of lung cancer induced by the combination of carcinogen administration and chronic pulmonary inflammation. Further refinement of this novel vaccine strategy and identification of shared ESC/tumor antigens may lead to immunotherapeutic options for lung cancer patients and, perhaps more importantly, could represent a first step toward the development of prophylactic cancer vaccines.

Research paper thumbnail of Helicobacter pylori Evolution: Lineage- Specific Adaptations in Homologs of Eukaryotic Sel1-Like Genes

PLoS Computational Biology, 2007

Geographic partitioning is postulated to foster divergence of Helicobacter pylori populations as ... more Geographic partitioning is postulated to foster divergence of Helicobacter pylori populations as an adaptive response to local differences in predominant host physiology. H. pylori's ability to establish persistent infection despite host inflammatory responses likely involves active management of host defenses using bacterial proteins that may themselves be targets for adaptive evolution. Sequenced H. pylori genomes encode a family of eight or nine secreted proteins containing repeat motifs that are characteristic of the eukaryotic Sel1 regulatory protein, whereas the related Campylobacter and Wolinella genomes each contain only one or two such ''Sel1-like repeat'' (SLR) genes (''slr genes''). Signatures of positive selection (ratio of nonsynonymous to synonymous mutations, d N /d S ¼ x. 1) were evident in the evolutionary history of H. pylori slr gene family expansion. Sequence analysis of six of these slr genes (hp0160, hp0211, hp0235, hp0519, hp0628, and hp1117) from representative East Asian, European, and African H. pylori strains revealed that all but hp0628 had undergone positive selection, with different amino acids often selected in different regions. Most striking was a divergence of Japanese and Korean alleles of hp0519, with Japanese alleles having undergone particularly strong positive selection (x J. 25), whereas alleles of other genes from these populations were intermingled. Homology-based structural modeling localized most residues under positive selection to SLR protein surfaces. Rapid evolution of certain slr genes in specific H. pylori lineages suggests a model of adaptive change driven by selection for fine-tuning of host responses, and facilitated by geographic isolation. Characterization of such local adaptations should help elucidate how H. pylori manages persistent infection, and potentially lead to interventions tailored to diverse human populations.

Research paper thumbnail of The Genome Sequence of Bluetongue Virus Type 2 from India: Evidence for Reassortment between Eastern and Western Topotype Field Strains

Journal of Virology, 2012

Bluetongue virus type 2, isolated in India in 1982 (IND1982/01), was obtained from the Orbivirus ... more Bluetongue virus type 2, isolated in India in 1982 (IND1982/01), was obtained from the Orbivirus Reference Collection at IAH Pirbright ( http://www.reoviridae.org/dsRNA_virus_proteins/ReoID/btv-2.htm#IND1982/01 ). Full genome sequencing and phylogenetic analyses show that IND1982/01 is a reassortant virus containing genome segments derived from both eastern and western topotypes. These data will help to identify further reassortment events involving this or other virus lineages in the subcontinent.

Research paper thumbnail of Control of Tumor-Associated Macrophage Alternative Activation by Macrophage Migration Inhibitory Factor

The Journal of Immunology, 2013

Tumor stromal alternatively activated macrophages are important determinants of antitumor T lymph... more Tumor stromal alternatively activated macrophages are important determinants of antitumor T lymphocyte responses, intratumoral neovascularization, and metastatic dissemination. Our recent efforts to investigate the mechanism of macrophage migration inhibitory factor (MIF) in antagonizing antimelanoma immune responses reveal that macrophage-derived MIF participates in macrophage alternative activation in melanoma-bearing mice. Both peripheral and tumor-associated macrophages (TAMs) isolated from melanoma bearing MIF-deficient mice display elevated proinflammatory cytokine expression and reduced anti-inflammatory, immunosuppressive, and proangiogenic gene products compared with macrophages from tumor-bearing MIF wild-type mice. Moreover, TAMs and myeloid-derived suppressor cells from MIF-deficient mice exhibit reduced T lymphocyte immunosuppressive activities compared with those from their wild-type littermates. Corresponding with reduced tumor immunosuppression and neo-angiogenic potential by TAMs, MIF deficiency confers protection against transplantable s.c. melanoma outgrowth and melanoma lung metastatic colonization. Finally, we report for the first time, to our knowledge, that our previously discovered MIF small molecule antagonist, 4-iodo-6-phenylpyrimidine, recapitulates MIF deficiency in vitro and in vivo, and attenuates tumor-polarized macrophage alternative activation, immunosuppression, neoangiogenesis, and melanoma tumor outgrowth. These studies describe an important functional contribution by MIF to TAM alternative activation and provide justification for immunotherapeutic targeting of MIF in melanoma patients.

Research paper thumbnail of SARS‐CoV‐2 variants and spike mutations involved in second wave of COVID‐19 pandemic in India

SARS‐CoV‐2 variants and spike mutations involved in second wave of COVID‐19 pandemic in India

Transboundary and Emerging Diseases, 2022

Research paper thumbnail of A Comprehensive Molecular Survey of Viral Pathogens Associated with Canine Gastroenteritis During 2018-21

A Comprehensive Molecular Survey of Viral Pathogens Associated with Canine Gastroenteritis During 2018-21

Viral pathogens account for major aetiology of canine gastroenteritis in India. However, till dat... more Viral pathogens account for major aetiology of canine gastroenteritis in India. However, till date, there was no structured comprehensive study reported on the viral aetiology of canine gastroenteritis in India. To elucidate this, 475 rectal swabs collected over a period of three years (2018-2021) from clinical canine gastroenteritis cases were screened by real-time PCR for the presence of six majorly known enteric viruses (Canine parvovirus -2 (CPV-2), canine distemper virus (CDV), canine adenovirus-2 (CAdV-2), canine corona virus (CCoV), canine astrovirus (CaAstV), canine rotavirus (CRV)). 71.6% of the samples were found to harbour at least one of the five viruses tested (CPV-2/2a/2b/2c, CDV, CAdV-2, CCoV and CaAstV), whereas, there was no evidence of CRV. The overall incidence rate for each virus was found highest at 64.8% for CPV-2/2a/2b/2c (2a: 21.1%, 2b: 77.4%, 2c: 1.5%), followed by 8% for CDV, 7.2% for CaAstV, 5.9% for CCoV and 4.6% for CAdV-2 with 16.8% incidence for coinfe...

Research paper thumbnail of Development and evaluation of NS1 protein based i-ELISA for serodiagnosis of Bluetongue disease

Development and evaluation of NS1 protein based i-ELISA for serodiagnosis of Bluetongue disease

Indian Journal of Small Ruminants, 2022

Research paper thumbnail of Comparative Neuropathology of Major Indian Bluetongue Virus Serotypes in a Neonatal BALB/c Mouse Model

Journal of Comparative Pathology, 2018

Bluetongue virus (BTV) is neurotropic in nature, especially in ruminant fetuses and in-utero infe... more Bluetongue virus (BTV) is neurotropic in nature, especially in ruminant fetuses and in-utero infection results in abortion and congenital brain malformations. The aim of the present study was to compare the neuropathogenicity of major Indian BTV serotypes 1, 2, 10, 16 and 23 by gross and histopathological lesions and virus distribution in experimentally infected neonatal BALB/c mice. Each BTV serotype (20 ml of inoculum containing 1 Â 10 5 tissue culture infectious dose [TCID] 50 /ml of virus) was inoculated intracerebrally into 3-day-old mice, while a control group was inoculated with mock-infected cell culture medium. Infection with BTV serotypes 1, 2 and 23 led to 65e70% mortality at 7e9 days post infection (dpi) and caused severe necrotizing encephalitis with neurodegenerative changes in neurons, swelling and proliferation of vascular endothelial cells in the cerebral cortex, cerebellum, midbrain and brainstem. In contrast, infection with BTV serotypes 10 and 16 led to 25e30% mortality at 9e11 dpi and caused mild neuropathological lesions. BTV antigen was detected by immunohistochemistry, direct fluorescence antibody technique and confocal microscopy in the cytoplasm of neuronal cells of the hippocampus, grey matter of the cerebral cortex and vascular endothelial cells in the midbrain and brainstem of BTV-1,-2,-10,-16 and-23 infected groups from 3 to 20 dpi. BTV nucleic acid was detected in the infected brain tissues from as early as 24 h up to 20 dpi by VP7 gene segment-based onestep reverse transcriptase polymerase chain reaction. This study of the relative neurovirulence of BTV serotypes is likely to help design suitable vaccination and control strategies for the disease.

Research paper thumbnail of Epidemiology of Bluetongue in India

Epidemiology of Bluetongue in India

Transboundary and Emerging Diseases, 2014

Bluetongue (BT) is an insectborne endemic disease in India. Although infections are observed in d... more Bluetongue (BT) is an insectborne endemic disease in India. Although infections are observed in domestic and wild ruminants, the clinical disease and mortality are observed only in sheep, especially in the southern states of the country. The difference in disease patterns in different parts of the country could be due to varied climatic conditions, sheep population density and susceptibility of the sheep breeds to BT. Over the five decades after the first report of BT in 1964, most of the known serotypes of bluetongue virus (BTV) have been reported from India either by virus isolation or by detection of serotype-specific antibodies. There have been no structured longitudinal studies to identify the circulating serotypes throughout the country. At least ten serotypes were isolated between 1967 and 2000 (BTV-1-4, 6, 9, 16-18, 23). Since 2001, the All-India Network Programme on Bluetongue and other laboratories have isolated eight different serotypes (BTV-1-3, 9, 10, 12, 16, 21). Genetic analysis of these viruses has revealed that some of them vary substantially from reference viruses, and some show high sequence identity with modified live virus vaccines used in different parts of the world. These observations have highlighted the need to develop diagnostic capabilities, especially as BT outbreaks are still declared based on clinical signs. Although virus isolation and serotyping are the gold standards, rapid methods based on the detection of viral nucleic acid may be more suitable for India. The epidemiological investigations also have implications for vaccine design. Although only a handful serotypes may be involved in causing outbreaks every year, the combination of serotypes may change from year to year. For effective control of BT in India, it may be pertinent to introduce sentinel and vector traps systems for identification of the circulating serotypes and to evaluate herd immunity against different serotypes, so that relevant strains can be included in vaccine formulations.

Research paper thumbnail of Quantitative and qualitative assessment of serum- and inflammatory mediator-induced migration of carp (Cyprinus carpio) head kidney neutrophils in vitro

Fish & Shellfish Immunology, 2006

A quantitative transmigration system, permitting the harvest of transmigrated cells for further a... more A quantitative transmigration system, permitting the harvest of transmigrated cells for further analysis, was used to study carp head kidney (HK) granulocyte migration in vitro. Pooled carp serum and leukotriene B4 (LTB-4), but not recombinant human C-X-C chemokine ligand 8 (rhCXCL8), recombinant human complement component 5a (rhC5a) or N-formyl-methionyl-leucyl-phenylalanine (FMLP) induced strong migration (up to 70%) of carp HK granulocytes. The transmigrated cells were viable (!96%) and uniform (purity !97%). After serum-as well as LTB-4-induced transmigration granulocytes produced the same amounts of reactive oxygen species (ROS) as non-migrated cells in HK cell suspension. Their morphology, staining characteristics and flow cytometric scatter characteristics, plus their ability to produce ROS characterised the transmigrated granulocytes as neutrophils. The quantitative transmigration system described here could also serve as an excellent tool for the selective attraction and isolation of highly purified carp neutrophils from HK cell suspensions.

Research paper thumbnail of A new multiplex RT-PCR assay for serotyping of bluetongue virus

IJBT Vol.19(3) [July 2020], Jul 1, 2020

Among all viral diseases affecting small ruminants, bluetongue is the one that affects adversely ... more Among all viral diseases affecting small ruminants, bluetongue is the one that affects adversely to an alarming extent. The current available diagnosis/serotyping of bluetongue virus (BTV) is time consuming, costly, and requires to screen individually for each of the 29 distinct serotypes. The present study was conducted with the objective of developing a multiplex reverse transcription PCR (mRT-PCR) assay for serotyping of BTV, especially for serotypes BTV-1, 2, 9, 12, 16, 21 and 23 predominantly circulating in India. The type specific primers for the selected BTV serotypes were designed targeting the serotype specific segment-2 region of BTV based on the reference serotype sequences of Indian isolates available in GenBank. The mRT-PCR was conducted in two groups-group A for BTV-1, 9, 12, 21 and group B for BTV-2, 16 and 23. A panel of 25 BT suspected clinical samples were typed by mRT-PCR. The results were further validated by the gold standard serum neutralization test (SNT). A seroprevalence of 60% for BTV-2, 10% for BTV-9, 15% for BTV-1, 10% for BTV-16 and 5% for BTV-23 were observed. Further, we noticed that there was a mixed serotype infection in 10% of BTV positive samples. In conclusion, we report the development of a novel mRT-PCR assay for a rapid and costeffective nucleic acid based serotyping of BTV having the specificity same as SNT.

Research paper thumbnail of Comparative evaluation of the effect of L-Arginine and L-Homoarginine supplementation on reproductive physiology in ewes

Comparative evaluation of the effect of L-Arginine and L-Homoarginine supplementation on reproductive physiology in ewes

Research in Veterinary Science

Research paper thumbnail of Comparative evaluation of the effect of L-Arginine and L-Homoarginine supplementation on reproductive physiology in ewes

Comparative evaluation of the effect of L-Arginine and L-Homoarginine supplementation on reproductive physiology in ewes

Research in Veterinary Science

Research paper thumbnail of First report of canine bufavirus in India

Archives of Virology, 2022

Canine bufavirus (CBuV), a novel protoparvovirus of dogs that is associated with enteric and resp... more Canine bufavirus (CBuV), a novel protoparvovirus of dogs that is associated with enteric and respiratory symptoms, has been reported only in Italy and China. The enteric prevalence of CBuV in India was investigated, and the nearly complete genome sequence (4292 bp) was amplified and reconstructed for one strain. A nucleotide sequence alignment indicated 93.42-98.81% identity to the other available CBuV sequences and 70.88-73.39% and 54.4-54.8% identity to human bufavirus and canine parvovirus 2 (CPV-2), respectively. The current strain is most closely related to Chinese CBuV strains, which together form an Asian lineage. This first report of the prevalence of CBuV in India emphasizes the need for further epidemiological surveillance.

Research paper thumbnail of Antagonistic effect of ursolic acid on Staphylococcal biofilms

Veterinary World, 2018

Aim: The present study was carried out to study the effect of ursolic acid (UA) as a potential an... more Aim: The present study was carried out to study the effect of ursolic acid (UA) as a potential anti-biofilm agent in dispersing the biofilm generated by Staphylococcus aureus isolated from milk samples of crossbred dairy cows on the day of drying. Further, in the S. aureus isolates, the presence of intracellular adherence gene locus involved in biofilm production (icaD) was investigated. Materials and Methods: A total of 50 S. aureus strains were isolated over a period of 3 months from 200 milk samples collected from crossbred dairy cows on the day of drying. These isolates were subjected for biofilm detection by Congo red agar (CRA), microtiter plate assay (MTP), and polymerase chain reaction specific for icaD gene. The antagonistic effect of biofilm formation by UA was studied using different concentrations (30 µg/ml and 60 µg/ml) of UA and compared with the control group. Results: Among the 50 S. aureus subjected for biofilm detection, 34 and 40 isolates were detected as biofilm agents by CRA and MTP methods, respectively. The in vitro studies on the effect of UA in inhibiting biofilm formation by S. aureus using MTP assay showed 71.5% and 48.6% inhibition at UA concentrations of 60 µg/ml and 30 µg/ml, respectively, with a significant difference (p<0.05) between the treated and untreated isolates, which was further evident by scanning electron microscopy. Interestingly, the isolates that were tested to be resistant through Antibiotic Sensitivity Test to commonly used antibiotics were found to be sensitive to all the tested antibiotics following UA treatment at both the tested concentrations. Furthermore, molecular detection of icaD gene for biofilm detection revealed that all the isolates that were positive by MTP had icaD gene. Conclusion: Increased incidence of biofilm agents in dairy infections must be considered as an alarming situation. UA treatment significantly enhanced the sensitivity of the microbial pathogens to commonly used antibiotics. Hence, attention must be paid toward implementation of new strategies such as therapeutic regimes with a combination of antibiotic and anti-biofilm agents for effective treatment of infections in dairy farms.

Research paper thumbnail of Type-specific seroprevalence of bluetongue in India during 2018 and 2019

Background and Aim: Bluetongue (BT) is a major disease of sheep and goats and is endemic to India... more Background and Aim: Bluetongue (BT) is a major disease of sheep and goats and is endemic to India. It is known to cause significant economic losses to the sheep industry. The current study aimed to determine the type-specific seroprevalence of BT in sheep population of India during 2018-2019. Materials and Methods: Blood samples (n=405) were collected from 6 months to 1 year old sheep from six districts (Nalgonda, Karimnagar, Khammam, Mahabubnagar, Warangal, and Ranga Reddy) of Telangana state, India. Group- and type-specific seroprevalence (against BT virus [BTV] serotypes BTV-1, 2, 4, 5, 9, 10, 12, 16, 21, 23, and 24) was studied by competitive enzyme-linked immunosorbent assay and serum neutralization test, respectively. Results: Results showed an overall seroprevalence of 14.81% (n=60) with the highest seroprevalence of 50% in Khammam district. Seroprevalence of BTV-1, 2, 4, 5, 9, 10, 12, 16, 21, 23, and 24 was noted as 16.66%, 11.66%, 31.66%, 11.66%, 05%, 6.66%, 16.66%, 8.33%, ...

Research paper thumbnail of Infection kinetics and antibody responses in Deccani sheep during experimental infection and superinfection with bluetongue virus serotypes 4 and 16

Veterinary World, 2019

Aim: The current study was designed to understand the infection kinetics and antibody responses o... more Aim: The current study was designed to understand the infection kinetics and antibody responses of major circulating serotypes of bluetongue virus (BTV) in India, i.e., BTV-4 and BTV-16 through experimental infection and superinfection of Deccani sheep, a popular breed of sheep found in the southern states of India. Materials and Methods: Experimental infection with 106 TCID50/ml BTV-4 was followed by superinfection with BTV-16 and vice versa. Along with observing for clinical signs and immunological responses in the experimentally infected sheep, the effect of infection of one specific serotype on the outcome of superinfection with a different serotype was also studied. Results: Certain interesting findings have been made in the course of experimental infection, such as prominent signs of infection in BTV-4 infection, mild or no clinical signs in BTV-16-infected and superinfected animals, and non-seroconversion of one of the BTV-16-superinfected animals. In addition, BTV was isolat...

Research paper thumbnail of Standardization and application of real-time polymerase chain reaction for rapid detection of bluetongue virus

Veterinary world, 2018

The present study was designed to standardize real-time polymerase chain reaction (PCR) for detec... more The present study was designed to standardize real-time polymerase chain reaction (PCR) for detecting the bluetongue virus from blood samples of sheep collected during outbreaks of bluetongue disease in the year 2014 in Andhra Pradesh and Telangana states of India. A 10-fold serial dilution of Plasmid PUC59 with bluetongue virus (BTV) NS3 insert was used to plot the standard curve. BHK-21 and KC cells were used for propagation of virus BTV-9 at a TCID50/ml of 10 ml and RNA was isolated by the Trizol method. Both reverse transcription-PCR and real-time PCR using TaqMan probe were carried out with RNA extracted from virus-spiked culture medium and blood to compare the sensitivity by means of finding out the limit of detection (LoD). The results were verified by inoculating the detected and undetected dilutions onto cell cultures with further cytological (cytopathic effect) and molecular confirmation (by BTV-NS1 group-specific PCR). The standardized technique was then applied to field ...

Research paper thumbnail of Dual Infection with Bluetongue Virus Serotypes and First-Time Isolation of Serotype 5 in India

Transboundary and emerging diseases, Jan 21, 2016

Bluetongue is endemic in India and has been reported from most Indian states. Of late, the clinic... more Bluetongue is endemic in India and has been reported from most Indian states. Of late, the clinical disease is most frequently seen in the states of Andhra Pradesh, Telangana (erstwhile Andhra Pradesh state), Tamil Nadu and Karnataka. Our analysis of diagnostic samples from bluetongue outbreaks during 2010-2011 from the state of Karnataka identified bluetongue virus (BTV) serotype 5 (BTV-5) for the first time in India. One of the diagnostic samples (CH1) and subsequent virus isolate (IND2010/02) contained both BTV-2 and BTV-5. Segment 2 (seg-2) sequence data (400 bp: nucleotides 2538-2921) for IND2010/02-BTV5, showed 94.3% nucleotide identity to BTV-5 from South Africa (Accession no. AJ585126), confirming the virus serotype and also indicating that Seg-2 was derived from a Western topotype, which is in contrast to serotype 2, that belongs to an Eastern topotype. BTV-5 has been recently reported from Africa, China, French islands and the Americas. Although the exact source of the Ind...

Research paper thumbnail of Role of eukaryotic Sel-1 like repeat containing genes in Helicobacter pylori evolution and pathogenesis

This study ~hp468: 594-617 189bp AmplifIcation of fragment of hepC for performing RT-PCR This stu... more This study ~hp468: 594-617 189bp AmplifIcation of fragment of hepC for performing RT-PCR This study ureA: 695•771 This study meA" 501-529 271bp AmplifICation of fragment of ureA for performing RT-PCR This study recA: 23-4 This study recA: 180-209 206bp AmolifICation of fragment of recA for performing RT-PCR This study GAPDH" 369-389 This study

Research paper thumbnail of Vaccination with Embryonic Stem Cells Protects against Lung Cancer: Is a Broad-Spectrum Prophylactic Vaccine against Cancer Possible?

PLoS ONE, 2012

The antigenic similarity between tumors and embryos has been appreciated for many years and refle... more The antigenic similarity between tumors and embryos has been appreciated for many years and reflects the expression of embryonic gene products by cancer cells and/or cancer-initiating stem cells. Taking advantage of this similarity, we have tested a prophylactic lung cancer vaccine composed of allogeneic murine embryonic stem cells (ESC). Naïve C57BL/6 mice were vaccinated with ESC along with a source of granulocyte macrophage-colony stimulating factor (GM-CSF) in order to provide immunostimulatory adjuvant activity. Vaccinated mice were protected against subsequent challenge with implantable Lewis lung carcinoma (LLC). ESC-induced anti-tumor immunity was not due to a non-specific ''allo-response'' as vaccination with allogeneic murine embryonic fibroblasts did not protect against tumor outgrowth. Vaccine efficacy was associated with robust tumor-reactive primary and memory CD8 + T effector responses, Th1 cytokine response, higher intratumoral CD8 + T effector/CD4 + CD25 + Foxp3 + T regulatory cell ratio, and reduced myeloid derived suppressor cells in the spleen. Prevention of tumorigenesis was found to require a CD8-mediated cytotoxic T lymphocyte (CTL) response because in vivo depletion of CD8 + T lymphocytes completely abrogated the protective effect of vaccination. Importantly, this vaccination strategy also suppressed the development of lung cancer induced by the combination of carcinogen administration and chronic pulmonary inflammation. Further refinement of this novel vaccine strategy and identification of shared ESC/tumor antigens may lead to immunotherapeutic options for lung cancer patients and, perhaps more importantly, could represent a first step toward the development of prophylactic cancer vaccines.

Research paper thumbnail of Helicobacter pylori Evolution: Lineage- Specific Adaptations in Homologs of Eukaryotic Sel1-Like Genes

PLoS Computational Biology, 2007

Geographic partitioning is postulated to foster divergence of Helicobacter pylori populations as ... more Geographic partitioning is postulated to foster divergence of Helicobacter pylori populations as an adaptive response to local differences in predominant host physiology. H. pylori's ability to establish persistent infection despite host inflammatory responses likely involves active management of host defenses using bacterial proteins that may themselves be targets for adaptive evolution. Sequenced H. pylori genomes encode a family of eight or nine secreted proteins containing repeat motifs that are characteristic of the eukaryotic Sel1 regulatory protein, whereas the related Campylobacter and Wolinella genomes each contain only one or two such ''Sel1-like repeat'' (SLR) genes (''slr genes''). Signatures of positive selection (ratio of nonsynonymous to synonymous mutations, d N /d S ¼ x. 1) were evident in the evolutionary history of H. pylori slr gene family expansion. Sequence analysis of six of these slr genes (hp0160, hp0211, hp0235, hp0519, hp0628, and hp1117) from representative East Asian, European, and African H. pylori strains revealed that all but hp0628 had undergone positive selection, with different amino acids often selected in different regions. Most striking was a divergence of Japanese and Korean alleles of hp0519, with Japanese alleles having undergone particularly strong positive selection (x J. 25), whereas alleles of other genes from these populations were intermingled. Homology-based structural modeling localized most residues under positive selection to SLR protein surfaces. Rapid evolution of certain slr genes in specific H. pylori lineages suggests a model of adaptive change driven by selection for fine-tuning of host responses, and facilitated by geographic isolation. Characterization of such local adaptations should help elucidate how H. pylori manages persistent infection, and potentially lead to interventions tailored to diverse human populations.

Research paper thumbnail of The Genome Sequence of Bluetongue Virus Type 2 from India: Evidence for Reassortment between Eastern and Western Topotype Field Strains

Journal of Virology, 2012

Bluetongue virus type 2, isolated in India in 1982 (IND1982/01), was obtained from the Orbivirus ... more Bluetongue virus type 2, isolated in India in 1982 (IND1982/01), was obtained from the Orbivirus Reference Collection at IAH Pirbright ( http://www.reoviridae.org/dsRNA_virus_proteins/ReoID/btv-2.htm#IND1982/01 ). Full genome sequencing and phylogenetic analyses show that IND1982/01 is a reassortant virus containing genome segments derived from both eastern and western topotypes. These data will help to identify further reassortment events involving this or other virus lineages in the subcontinent.

Research paper thumbnail of Control of Tumor-Associated Macrophage Alternative Activation by Macrophage Migration Inhibitory Factor

The Journal of Immunology, 2013

Tumor stromal alternatively activated macrophages are important determinants of antitumor T lymph... more Tumor stromal alternatively activated macrophages are important determinants of antitumor T lymphocyte responses, intratumoral neovascularization, and metastatic dissemination. Our recent efforts to investigate the mechanism of macrophage migration inhibitory factor (MIF) in antagonizing antimelanoma immune responses reveal that macrophage-derived MIF participates in macrophage alternative activation in melanoma-bearing mice. Both peripheral and tumor-associated macrophages (TAMs) isolated from melanoma bearing MIF-deficient mice display elevated proinflammatory cytokine expression and reduced anti-inflammatory, immunosuppressive, and proangiogenic gene products compared with macrophages from tumor-bearing MIF wild-type mice. Moreover, TAMs and myeloid-derived suppressor cells from MIF-deficient mice exhibit reduced T lymphocyte immunosuppressive activities compared with those from their wild-type littermates. Corresponding with reduced tumor immunosuppression and neo-angiogenic potential by TAMs, MIF deficiency confers protection against transplantable s.c. melanoma outgrowth and melanoma lung metastatic colonization. Finally, we report for the first time, to our knowledge, that our previously discovered MIF small molecule antagonist, 4-iodo-6-phenylpyrimidine, recapitulates MIF deficiency in vitro and in vivo, and attenuates tumor-polarized macrophage alternative activation, immunosuppression, neoangiogenesis, and melanoma tumor outgrowth. These studies describe an important functional contribution by MIF to TAM alternative activation and provide justification for immunotherapeutic targeting of MIF in melanoma patients.

Research paper thumbnail of SARS‐CoV‐2 variants and spike mutations involved in second wave of COVID‐19 pandemic in India

SARS‐CoV‐2 variants and spike mutations involved in second wave of COVID‐19 pandemic in India

Transboundary and Emerging Diseases, 2022

Research paper thumbnail of A Comprehensive Molecular Survey of Viral Pathogens Associated with Canine Gastroenteritis During 2018-21

A Comprehensive Molecular Survey of Viral Pathogens Associated with Canine Gastroenteritis During 2018-21

Viral pathogens account for major aetiology of canine gastroenteritis in India. However, till dat... more Viral pathogens account for major aetiology of canine gastroenteritis in India. However, till date, there was no structured comprehensive study reported on the viral aetiology of canine gastroenteritis in India. To elucidate this, 475 rectal swabs collected over a period of three years (2018-2021) from clinical canine gastroenteritis cases were screened by real-time PCR for the presence of six majorly known enteric viruses (Canine parvovirus -2 (CPV-2), canine distemper virus (CDV), canine adenovirus-2 (CAdV-2), canine corona virus (CCoV), canine astrovirus (CaAstV), canine rotavirus (CRV)). 71.6% of the samples were found to harbour at least one of the five viruses tested (CPV-2/2a/2b/2c, CDV, CAdV-2, CCoV and CaAstV), whereas, there was no evidence of CRV. The overall incidence rate for each virus was found highest at 64.8% for CPV-2/2a/2b/2c (2a: 21.1%, 2b: 77.4%, 2c: 1.5%), followed by 8% for CDV, 7.2% for CaAstV, 5.9% for CCoV and 4.6% for CAdV-2 with 16.8% incidence for coinfe...