Nutrient Deficiencies and Potential Alteration in Plasma Levels of Naturally Acquired Malaria-Specific Antibody Responses in Tanzanian Children (original) (raw)

Impact of IgG response to malaria-specific antigens and immunity against malaria in pre-school children in Ghana. A cluster randomized, placebo-controlled trial

2021

Background Iron fortification and micronutrient initiatives, specifically, vitamin A, and zinc supplementation are the most cost-effective developmental strategies against malnutrition and health emergencies in pre-school children. Iron-deficiency among pre-school children have been documented, however, studies evaluating the impact of immunoglobulin G (IgG) isotype responses among iron-fortified pre-school children in malaria endemic communities has not been assessed. We evaluated the impact of iron fortification on the IgG responses to GLURP R0, GLURP R2 and MSP3 FVO malaria-specific antigens among pre-school children in malaria endemic areas. Methods This community-based, placebo-controlled, double-blinded, cluster-randomized trial study was conducted in Wenchi Municipal and Tain District of Bono Region. The trial was registered at ClinicalTrials.gov-registered trial (Identifier: NCT01001871). Ethical approval was obtained and informed consent were sought from each participant pa...

Effect of Supplementation with Zinc and Other Micronutrients on Malaria in Tanzanian Children: A

2016

Background: It is uncertain to what extent oral supplementation with zinc can reduce episodes of malaria in endemic areas. Protection may depend on other nutrients. We measured the effect of supplementation with zinc and other nutrients on malaria rates. Methods and Findings: In a 262 factorial trial, 612 rural Tanzanian children aged 6–60 months in an area with intense malaria transmission and with height-for-age z-score#21.5 SD were randomized to receive daily oral supplementation with either zinc alone (10 mg), multi-nutrients without zinc, multi-nutrients with zinc, or placebo. Intervention group was indicated by colour code, but neither participants, researchers, nor field staff knew who received what intervention. Those with Plasmodium infection at baseline were treated with artemether-lumefantrine. The primary outcome, an episode of malaria, was assessed among children reported sick at a primary care clinic, and pre-defined as current Plasmodium infection with an inflammatory...

Comparative analysis of the Immunoglobulin G antibodies (IgG and IgG subclass) responses in children (≤15 years) with severe and uncomplicated malaria in Buea, South West region, Cameroon

Infectious Diseases and Herbal Medicine, 2020

Studies assessing the immunoglobulin G (IgG) antibody responses in severe malaria are not readily available. This study was designed to compare the IgG and IgG1-4 antibody responses in severe malaria and its major clinical presentations (cerebral malaria, severe malarial anemia and respiratory distress) in children (≤15 years) in Buea, Cameroon. In a hospital-based cross-sectional comparative study, children presenting for consultation at the outpatient department/Emergency unit of the Buea Regional Hospital were enrolled and assigned into one of three groups: severe malaria, uncomplicated malaria and negative controls. Baseline characteristics were determined; blood glucose level was measured by glucometer, complete blood count was performed using an automated heamatology analyser and participants were screened for malaria parasites by light microscopy and severe malaria was categorized based on WHO criteria. Total IgG and IgG1-4 antibodies were measured using standard ELISA with Plasmodium falciparum 19-KDa C-terminal region of merozoite surface protein 1 (P.fMSP-1 19) antigen as capture antigen. A total of 236 participants were enrolled comprising: 66 severe malaria, 70 uncomplicated malaria and 100 negative controls. The participants in the different groups were similar with regards to their ages (p=0.06) and gender (p=0.900). Children with severe malaria had significantly higher levels of anti-P.fMSP-1 19 IgG4 (p<0.0001) antibodies and significantly lower levels of anti-P.fMSP-1 19 IgG1 (p<0.0001) and IgG3 (p<0.0001) antibodies. There was no significant variation in the IgG antibody responses between the major clinical forms of severe malaria. The study finding of significantly higher levels of the non-cytophilic antibody IgG4 is suggestive of the role the antibody plays in the pathogenesis of severe malaria. Larger studies investigating how these immune effector cells vary in the major phenotypes of severe malaria are recommended.

Plasma zinc concentrations are depressed during the acute phase response in children with falciparum malaria

The Journal of nutrition, 2005

Plasma concentrations of some micronutrients are altered in the setting of acute infectious or inflammatory stress. Previous studies have provided conflicting evidence concerning the extent and direction of changes in plasma zinc concentrations during the acute phase response. We carried out an observational cohort study in 689 children enrolled in a randomized trial of zinc supplementation during acute falciparum malaria in order to evaluate the relation between plasma zinc concentration and the acute phase response. Plasma zinc was measured by atomic absorption spectrophotometry. On admission, 70% of all subjects had low plasma zinc (<9.2 micromol/L). Multivariate analysis of predictors of admission plasma zinc showed that admission C-reactive protein (CRP), parasite density, and study site were the most important predictors. Predictors of changes in plasma zinc from admission to 72 h included baseline CRP, change in CRP, treatment group, study site, and baseline zinc concentra...

Effect of IgG3 Hinge Region Length Polymorphisms on Iron Fortification among Rural Pre-School Ghanaian Children and Its Associated Risk to Malaria and Anaemia

2021

Sub-Saharan African pre-school children have an interdependence among immune response, infection resistance and adaptive effect of the dietary intake. However, the long hinge region of immunoglobulin G3 makes binding easy to malaria antigens and receptors, eliciting a more protective response among subclasses of immunoglobulin G. However, it is unknown if iron-containing multimicronutrients are associated with risk of anaemia and malaria in pre-school children with hinge region G3 immunoglobulin polymorphism living in high malaria transmission areas. We aimed to determine the impact of iron fortification in pre-school children with immunoglobulin G3 hinge region length polymorphisms and their associated risk of malaria and anaemia in rural Ghana. This retrospective controlled, double blind, randomized population study was conducted over six months in rural Ghana among 6 to 35-month-old infants and young children. Participants were randomly allocated either ironfree multimicronutrien...

Age-dependent association between IgG2 and IgG3 subclasses to Pf332-C231 antigen and protection from malaria, and induction of protective antibodies by sub-patent malaria infections, in Daraweesh

Vaccine, 2010

The certainty of the protective role of acquired immunity in malaria is the major drive for malaria vaccine development. In this study, we measured the levels of total IgG and IgG subclasses to four candidate malaria vaccine antigens; MSP2-3D7, MSP2-FC27, AMA-1 and Pf332-C231, in plasma obtained from a cohort of 136 donors from Daraweesh in Sudan. The cohort was followed for malaria infection for 9 years. After an initial analysis, the immune response to Pf332-C231 antigen was the only one found associated with protection, thus taken for further analysis. The number of previous clinical malaria episodes experienced by the donors was used as an index for relative protection. The number of these episodes was found to be negatively correlated with the levels of pre-existing total IgG, IgG2 and IgG3 to Pf332-C231 (correlation coefficient, CC – 0.215, p = 0.012; CC – 0.195, p = 0.023 and CC – 0.211, p = 0.014, respectively), and also with age (CC – 0.311, p < 0.001). Unexpectedly, equal levels of Pf332-C231 antibodies were induced by both patent and sub-patent infections regardless of the number of previous malaria episodes (1–7). Combining the correlation analysis with a multi-linear regression, three variable markers for protection were emerged, two age-dependent, the antibody response to Pf332-C231 and an unidentified marker (likely immune response to other antigens), and the third was an age-independent unidentified marker (possibly gene polymorphisms). In conclusion, this report suggests a protective effect for IgG subclasses to Pf332-C231 antigen against malaria.