Breadth of humoral immune responses to the C-terminus of the circumsporozoite protein is associated with protective efficacy induced by the RTS,S malaria vaccine.

Breadth of humoral immune responses to the C-terminus of the circumsporozoite protein is associated with protective efficacy induced by the RTS,S malaria vaccine. Vaccine. 2021 Jan 08;: Authors: Chaudhury S, MacGill RS, Early AM, Bolton JS, King CR, Locke E, Pierson T, Wirth DF, Neafsey DE, Bergmann-Leitner ES Abstract The circumsporozoite protein (CSP) is the main surface antigen of malaria sporozoites, a prime vaccine target, and is known to have polymorphisms in the C-terminal region. Vaccines using a single allele may have lower efficacy against genotypic variants. Recent studies have found evidence suggesting the efficacy of the CSP-based RTS,S malaria vaccine may be limited against P. falciparum CSP alleles that diverge from the 3D7 vaccine allele, particularly in this polymorphic C-terminal region. In order to assess the breadth of the RTS,S-induced antibody responses against CSP C-terminal antigenic variants, we used a novel multiplex assay to measure reactivity of serum samples from a recent RTS,S study against C-terminal peptides from 3D7 and seven additional CSP alleles that broadly represent the genetic diversity found in circulating P. falciparum field isolates. We found that responses to the variants showed, on average, a ~ 30-fold reduction in reactivity relative to the vaccine-matched 3D7 allele. The extent of this reduction, ranging from 21 to 69-fold, correlated with the number of polymorphisms between the variant...
Source: Vaccine - Category: Allergy & Immunology Authors: Tags: Vaccine Source Type: research