Chatchai Tayapiwatana - Academia.edu (original) (raw)

Papers by Chatchai Tayapiwatana

Journal of Genetic Syndromes & Gene Therapy, Nov 22, 2013

e-Polymers, 2008

To obtain molecularly imprinted polymers capable of selective rebinding with nicotinamide (NAM), ... more To obtain molecularly imprinted polymers capable of selective rebinding with nicotinamide (NAM), NAM imprinted polymers were synthesized via bulk polymerization using various functional monomers and cross-linkers. The NAM recognition properties of these polymers were investigated in organic and aqueous solvents by equilibrium rebinding experiments. The results show that the imprinted polymer prepared using 1:4:4 molar ratio of NAM/MAA/TRIM in dichloromethane exhibited the greatest NAM binding capacity and selectivity. This polymer is potentially valuable for the analysis of NAM in complex matrices where selective isolation and identification are needed.

Journal of Associated Medical Sciences, 2022

Background: Neck pain is associated with scapular dyskinesis and impaired axio-scapular and shoul... more Background: Neck pain is associated with scapular dyskinesis and impaired axio-scapular and shoulder muscle activity and function. However, there is little research on force steadiness, specifically during shoulder motion in patients with neck pain with scapular dyskinesis. Its relationship with characteristics of neck pain is also unknown. Objectives: to investigate force steadiness at 20% and 50% of MVC of shoulder abduction (30 degrees) in persons with neck pain with scapular dyskinesis compared to asymptomatic controls and to determine its relationships with characteristics of neck pain. Materials and methods: Fifty-two women and men (26 neck pain with scapular dyskinesis and 26 asymptomatic controls) were recruited to the study. Force steadiness of 30 degrees of shoulder abduction was measured at 20% and 50% of maximal voluntary contraction (MVC) and coefficient of variation (CV) of force values were calculated. Characteristics of neck pain included neck pain intensity, duratio...

Antibiotics

Isoniazid (INH) is an antibiotic that is widely used to treat tuberculosis (TB). Adaptation to en... more Isoniazid (INH) is an antibiotic that is widely used to treat tuberculosis (TB). Adaptation to environmental stress is a survival strategy for Mycobacterium tuberculosis and is associated with antibiotic resistance development. Here, mycobacterial adaptation following INH treatment was studied using a multi-stress system (MS), which mimics host-derived stress. Mtb H37Rv (drug-susceptible), mono-isoniazid resistant (INH-R), mono-rifampicin resistant (RIF-R), and multidrug-resistant (MDR) strains were cultivated in the MS with or without INH. The expression of stress-response genes (hspX, tgs1, icl1, and sigE) and lipoarabinomannan (LAM)-related genes (pimB, mptA, mptC, dprE1, dprE2, and embC), which play important roles in the host–pathogen interaction, were measured using real-time PCR. The different adaptations of the drug-resistant (DR) and drug-susceptible (DS) strains were presented in this work. icl1 and dprE1 were up-regulated in the DR strains in the MS, implying their roles ...

BMC Biotechnology, Jan 29, 2008

Background: Expression of intracellular antibodies (intrabodies) has become a broadly applicable ... more Background: Expression of intracellular antibodies (intrabodies) has become a broadly applicable technology for generation of phenotypic knockouts in vivo. The method uses surface depletion of cellular membrane proteins to examine their biological function. In this study, we used this strategy to block the transport of cell surface molecule CD147 to the cell membrane. Phage display technology was introduced to generate the functional antibody fragment to CD147, and we subsequently constructed a CD147-specific scFv that was expressed intracellularly and retained in the endoplasmic reticulum by adenoviral gene transfer. Results: The recombinant antibody fragments, Fab and scFv, of the murine monoclonal antibody (clone M6-1B9) reacted specifically to CD147 by indirect enzyme-linked immunosorbent assays (ELISA) using a recombinant CD147-BCCP as a target. This indicated that the Fab-and scFv-M6-1B9 displaying on phage surfaces were correctly folded and functionally active. We subsequently constructed a CD147-specific scFv, scFv-M6-1B9-intrabody, in 293A cells. The expression of CD147 on 293A cell surface was monitored at 36 h after transduction by flow cytometry and demonstrated remarkable reduction. Colocalization of scFv-M6-1B9 intrabody with CD147 in the ER network was depicted using a 3D deconvolution microscopy system. Conclusion: The results suggest that our approach can generate antibody fragments suitable for decreasing the expression of CD147 on 293A cells. This study represents a step toward understanding the role of the cell surface protein, CD147.

International Journal of Molecular Sciences, Nov 30, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

PubMed, Aug 14, 2023

Background: Adult-onset immunodeficiency (AOID) is associated with the presence of anti-interfero... more Background: Adult-onset immunodeficiency (AOID) is associated with the presence of anti-interferon gamma autoantibodies (anti-IFN-γ autoAbs), which neutralizes IFN-γ signaling and leads to susceptibility to intracellular opportunistic infections. However, measuring neutralizing autoAbs is not practical for general clinical laboratories. Objective: This study aims to develop a competitive immunochromatographic (IC) strip test for detecting autoAbs that recognize the same epitope as a potent neutralizing antibody. Methods: The competitive IC strip test detecting autoAbs that recognize the same epitope as mouse anti-IFN-γ monoclonal antibody, clone B27 (B27 mAb) was fabricated and used to determine B27 epitope recognizing autoAb (B27 AAb) in AOID plasma. The competitive ELISA was used as a comparative method. AR patients. Results: The efficacy of the IC strip test was compared with competitive ELISA and found a percent positive agreement of 91.30%, a percent negative agreement of 79.31%, and a percent overall agreement of 84.62%. Conclusions: The results from the competitive IC strip test were consistent with those from competitive ELISA, indicating that the generated IC strip could detect B27 AAb in AOID plasma.

Analytica Chimica Acta, Sep 1, 2019

Integrated Ferroelectrics, Jun 20, 2014

ABSTRACT The ankyrin repeat (AR) can be used as a versatile scaffold for protein–protein interact... more ABSTRACT The ankyrin repeat (AR) can be used as a versatile scaffold for protein–protein interactions. It consists of a 33-residues sequence motif found in proteins with diverse functions, such as transcription initiation, cell cycle regulation, cytoskeletal integrity, ion transport, and cell–cell signaling. Using AR with high affinity for the Escherichia coli maltose binding protein (MBP) as our model system, we explored a structure-based computational protocol to probe and characterize binding affinity hot-spots at protein–protein interfaces. In this study, the long time scale dynamics simulations with GPU accelerated molecular dynamics (MD) simulations in AMBER12 have been performed to locate the hot-spots of protein-protein interaction by the analysis of the Molecular Mechanics–Poisson-Boltzmann Surface Area/Generalized Born Solvent Area (MM-PBSA/GBSA) of the MD trajectories. The two designed AR systems with different binding affinities from ELISA were simulated. Our calculations gave the absolute binding affinity predictions which are in agreement with the kinetic experiment. The difference in binding affinity of the two selected clones is due to the framework mutations which are mostly conserved at a β-hairpin/loop region. AR domain is most probably not affected by the alteration of this framework from the long time scale MDs.

2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC)

Protease inhibitors (PIs) have been used to treat various types of symptoms or diseases. However,... more Protease inhibitors (PIs) have been used to treat various types of symptoms or diseases. However, current PIs block the protease activity by targeting the protease active site which has been shown to be sensitive to the off-target effect due to crossreactivity with protease homologues. An alternative approach to inhibiting protease activity is to target the substrate, specifically by blocking the substrate cleavage site. We propose to employ synthetic biology approach to create a synthetic E. coli to be used as a protease inhibitor detecting biomachine that can effectively isolate intrabodies, a new generation of protease inhibitor drug. The in vivo selection system, comprised of three biological devices, i.e., protease activity detector, protease generator and protease blocking devices, is based on the ability to transport folded protein of the E. coli twin-arginine translocation (Tat) pathway and antibiotic resistance of TEM-1 β-lactamase (Bla) using as reporter protein. By linking protease degradation to antibiotic resistance, we can isolate the suitable intrabodies simply by plating cells containing appropriate devices on solid agar containing β-lactam ring antibiotics. As a proof of concept, we applied a previously isolated HIV-1 p17 intrabody (scFvp17) that binds to the C-terminus of HIV-1 matrix protein (p17) to our synthetic E. coli. This work demonstrated that binding of scFvp17 to its epitope on p17 can physically interfere with HIV-1 protease activity and inhibit proteolytic cleavage at the p17Δp24 cleavage site when expressed in the designed format. The device was optimized by varying plating conditions such as incubation temperatures, induction levels, and Carbenicillin concentrations which was used as selection pressure. The feasibility of this assay has opened the door to protease inhibitor selection which can be used for various applications such as optimization of the current protease inhibitors and selection of new ones.

Assembly and budding in the late-stage of human immunodeficiency virus type 1 (HIV-1) production ... more Assembly and budding in the late-stage of human immunodeficiency virus type 1 (HIV-1) production relies on the polymerization of Gag protein at the inner leaflet of the plasma membrane. We previously generated an ankyrin repeat protein (Ank1D4) that specifically interacts with the CAp24 protein. This study aimed to improve the binding activity of Ank1D4 by generating two platforms for the Ank1D4 dimer. The design of these constructs featured a distinct orientation of monomeric Ank1D4 connected by a linker peptide (G S) . The binding surfaces in either dimer generated from the C-terminus of the Ank1D4 monomer linked with the N-terminus of another monomer (Ank1D4 ) or its inverted form (Ank1D4 ), similar to monomeric Ank1D4. The interaction of Ank1D4 with CAp24 from capture ELISA was significantly greater than that of Ank1D4 and the parental Ank1D4. The bifunctional characteristic of Ank1D4 was further demonstrated using sandwich ELISA. The binding kinetics of these ankyrins were eval...

PLOS ONE

Genome editing in human induced pluripotent stem cells (hiPSCs) offers a potential tool for study... more Genome editing in human induced pluripotent stem cells (hiPSCs) offers a potential tool for studying gene functions in disease models and correcting genetic mutations for cell-based therapy. Precise transgene insertion in hiPSCs represents a significant challenge. In the past decade, viral transduction has been widely used due to its high transduction efficiency; however, it can result in random transgene integration and variable transgene copy numbers. Non-viral-based strategies are generally safer but limited by their low transfection efficiency in hiPSCs. Recently, genome engineering using adeno-associated virus (AAV) vectors has emerged as a promising gene delivery approach due to AAVs’ low immunogenicity, toxicity, and ability to infect a broad range of cells. The following protocol describes the workflow for genome editing in hiPSCs using the CRISPR/Cas9 ribonucleoprotein (RNP) complex combined with the recombinant AAV serotype 6 (AAV6) donor vectors to introduce a gene of int...

IEEE Conference Proceedings, 2017

Viruses, 2017

Human immunodeficiency virus (HIV) is a causative agent of acquired immune deficiency syndrome (A... more Human immunodeficiency virus (HIV) is a causative agent of acquired immune deficiency syndrome (AIDS). Highly active antiretroviral therapy (HAART) can slow down the replication of HIV-1, leading to an improvement in the survival of HIV-1-infected patients. However, drug toxicities and poor drug administration has led to the emergence of a drug-resistant strain. HIV-1 immunotherapy has been continuously developed, but antibody therapy and HIV vaccines take time to improve its efficiency and have limitations. HIV-1-specific chimeric antigen receptor (CAR)-based immunotherapy founded on neutralizing antibodies is now being developed. In HIV-1 therapy, anti-HIV chimeric antigen receptors showed promising data in the suppression of HIV-1 replication; however, autologous transfusion is still a problem. This has led to the development of effective peptides and proteins for an alternative HIV-1 treatment. In this paper, we provide a comprehensive review of potent anti-HIV-1 peptides and proteins that reveal promising therapeutic activities. The inhibitory mechanisms of each therapeutic molecule in the different stages of the HIV-1 life cycle will be discussed herein.

Frontiers in Immunology, 2019

Adult-onset immunodeficiency (AOID) with anti-interferon-γ (IFN-γ) autoantibodies (autoAbs) is an... more Adult-onset immunodeficiency (AOID) with anti-interferon-γ (IFN-γ) autoantibodies (autoAbs) is an emerging immunodeficiency syndrome in Asian countries. The presence of neutralizing anti-IFN-γ autoAbs are significantly associated with severe disseminated opportunistic infections. However, the characteristics of the neutralizing antibodies in patients are poorly defined. To better understand the properties of the anti-IFN-γ autoAbs in patients with opportunistic infections, a simplified competitive-binding ELISA was developed. The domains recognized by anti-IFN-γ autoAbs were assessed based on their competition with commercial neutralizing mouse anti-IFN-γ monoclonal antibodies (mAbs). First, the binding affinity and neutralizing capacity of these mAbs (clones B27, B133.5, and MD-1) were characterized. Kinetic analysis and epitope binning using bio-layer interferometry showed the comparable binding affinity of these mAbs to full-length IFN-γ and to the adjacent binding region. These mAbs did not recognize the synthetic 20-mer peptides and inhibited IFN-γ-mediated functions differently. In a competitive-binding ELISA, the anti-IFN-γ autoAbs in AOID serum blocked B27, B133.5, and MD-1 mAb binding. This evidence suggested that the autoAbs that competed with neutralizing mouse anti-IFN-γ mAbs recognized a discontinuous epitope of homodimeric IFN-γ as these mAbs. The patient autoAbs that recognized the B27 epitope exhibited strong neutralizing activity that was determined by the functional analysis. Our results demonstrated the heterogeneity of the autoAbs against IFN-γ in AOID patients and the different patterns among individuals. These data expand upon the fundamental knowledge of neutralizing anti-IFN-γ autoAbs in AOID patients.

International Journal of Molecular Sciences

Several anti-HIV scaffolds have been proposed as complementary treatments to highly active antire... more Several anti-HIV scaffolds have been proposed as complementary treatments to highly active antiretroviral therapy. AnkGAG1D4, a designed ankyrin repeat protein, formerly demonstrated anti-HIV-1 replication by interfering with HIV-1 Gag polymerization. However, the improvement of the effectiveness was considered. Recently, the dimeric molecules of AnkGAG1D4 were accomplished in enhancing the binding activity against HIV-1 capsid (CAp24). In this study, the interaction of CAp24 against the dimer conformations was elucidated to elaborate the bifunctional property. The accessibility of the ankyrin binding domains was inspected by bio-layer interferometry. By inverting the second module of dimeric ankyrin (AnkGAG1D4NC-CN), the CAp24 interaction KD was significantly reduced. This reflects the capability of AnkGAG1D4NC-CN in simultaneously capturing CAp24. On the contrary, the binding activity of dimeric AnkGAG1D4NC-NC was indistinguishable from the monomeric AnkGAG1D4. The bifunctional pr...

Vaccine

Background CoronaVac was administered as the primary COVID-19 vaccine for Thai health care worker... more Background CoronaVac was administered as the primary COVID-19 vaccine for Thai health care workers (HCWs) in early 2021 in response to the epidemic of new variants. This study aimed to evaluate the dynamic of humoral immune response as well as the short-term side effects resulting from the booster dose of BNT162b2 following completion of a CoronaVac double-dose in Thai HCWs. Methods This study was conducted at a teaching hospital in Northern Thailand during August and September 2021. The participants were 50 HCWs who were vaccinated with 2 doses of CoronaVac and were scheduled to receive a booster dose of BNT162b2. Anti-SARS-CoV-2 IgG antibodies levels and short-term side effects were assessed. The anti-RBD level was determined using Architect SARS-CoV-2 IgG II Quant (Abbott). Result Of the 50 participants, 37 were female. The median age was 33.0 years old. The average time between the second CoronaVac shot and the BNT162b2 booster shot was 81.7 days (SD = 25.0). The median anti-SARS-CoV-2 IgG antibody level on booster vaccination date, as well as day 14, and day 28 after the booster were 335.5 AU/ml, 31,613.5 AU/ml, and 20,311.9 AU/ml, respectively. Fourteen days after the booster, 94% of participants had anti-SARS-CoV-2 IgG antibody levels higher than 50.0 AU/ml. Being female, higher log anti-SARS-CoV-2 IgG antibodies prior to booster vaccination, and longer interval between the second shot and the booster shot were found to be significantly associated with higher levels of anti-SARS-CoV-2 IgG antibodies at both day 14 and day 28 after the booster. There were no reports of serious adverse events. Conclusion A booster dose of BNT162B2 promoted a high level of anti-SARS-CoV-2 IgG antibodies among HCWs who received 2 doses of CoronaVac. The time between the second CoronaVac shot and the booster shot should be at least three months. There were no severe adverse effects observed.

Chiang Mai University Journal of Natural Sciences, 2018

Ankyrin repeat protein is a novel class of non-antibody binding protein that can be applied as an... more Ankyrin repeat protein is a novel class of non-antibody binding protein that can be applied as an alternative antiretroviral agent. Engineered ankyrin targeting the HIV-1 matrix (MA) would be a promising agent to interfere with HIV replication, since MA plays a major role in multiple processes of the viral life cycle. In this study, MA-specific ankyrin (Ank GAG G31) was isolated from an artificial ankyrin library using a semi-automated selection process with biotinylated MA-streptavidin magnetic beads. The Ank GAG G31-recognition site on MA was determined using both indirect and competitive ELISAs with overlapping MA tri-helical fragments and pentadecapeptides. The Ank GAG G31 showed the highest binding signal to the MA-fragments covering helices 2-3-4 and peptides corresponding to helix 2 (residues 25-43), which were found as the target epitope. This finding was further analyzed by molecular modeling and docking. The rational models of Ank GAG G31-MA complex indicated that the strong binding interaction was shown on helix 2 at key residues K27 MA , K30 M , and K32 MA. Taken together, the identification of the binding domain on the MA target improves our understanding of the Ank GAG G31-MA interaction and provides the information necessary to design innovative protein targeting of the MA protein.