Parasite Specific Antibody Increase Induced by an Episode of Acute P. falciparum Uncomplicated Malaria

Abstract

IntroductionThere is no approved vaccine for malaria, and precisely how human antibody responses to malaria parasite components and potential vaccine molecules are developed and maintained remains poorly defined. In this study, antibody anamnestic or memory response elicited by a single episode of P. falciparum infection was investigated.MethodsThis study involved 362 malaria patients aged between 6 months to 60 years, of whom 19% were early-diagnosed people living with HIV/AIDS (PLWHA). On the day malaria was diagnosed and 42 days later, blood specimens were collected. Parasite density, CD4+ cells, and antibodies specific to synthetic peptides representing antigenic regions of the P. falciparum proteins GLURP, MSP3 and HRPII were measured.ResultsOn the day of malaria diagnosis, Immunoglobulin (IgG) antibodies against GLURP, MSP3 and HRP II peptides were present in the blood of 75%, 41% and 60% of patients, respectively. 42 days later, the majority of patients had boosted their serum IgG antibody more than 1.2 fold. The increase in level of IgG antibody against the peptides was not affected by parasite density at diagnosis. The median CD4+ cell counts of PLWHAs and HIV negative individuals were not statistically different, and median post-infection increases in anti-peptide IgG were similar in both groups of patients.ConclusionIn the majority (70%) of individuals, an infection of P. falciparum elicits at least 20% increase in level of anti-parasite IgG. This boost in anti-P. falciparum IgG is not affected by parasite density on the day of malaria diagnosis, or by HIV status.

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

“…This observation was consistent with a study conducted in Malawi [28]. On the contrary, Kaddumukasa and colleagues reported that gender was not significantly associated with increase IgG response against GLURP, HRPII and MSP3 antigens in Uganda [29].…”

Serology reveals micro-differences in Plasmodium falciparum transmission in the Hohoe municipality of Ghana

“…Also, parasitaemic children in the rural communities had higher total IgG responses to MSP2-3D7 and CSP, while no differences were observed in the urban settlements between parasitaemic and non-parasitaemic children. Parasite specific antibody responses can be boosted by Plasmodium infection by an estimated increase in level (Kaddumukasa et al, 2015) and thus the high responses observed in the rural settlements are likely to reflect the higher parasite prevalence there. The low responses and low seroprevalence in the urban settlement may be due to the awareness of the population about malaria-related illness and protecting children from infection risk.…”

Suitability of IgG responses to multiple Plasmodium falciparum antigens as markers of transmission intensity and pattern

“…Infection with P . falciparum is generally thought to boost parasite-specific antibody responses by about 20% [ 44 ]. In the current study, parasitaemic (microscopic and sub-microscopic individuals) in both Hohoe and Keta districts had higher antibody levels compared to the non-parasitaemic individuals ( S1 Fig ) indicating that persisting parasitaemia does trigger continuous antibody production [ 45 , 46 ].…”