Analysis of antibody responses to selected Plasmodium falciparum merozoite surface antigens in mild and cerebral malaria and associations with clinical outcomes.

Merozoite surface proteins (MSPs) are critical for parasite invasion; they represent attractive targets for antibody-based protection against clinical malaria. To identify protection-associated target MSPs, the present study analysed antibody responses to whole merozoite extract (ME) and to defined MSP recombinant antigens in hospitalized patients from a low endemic urban area as a function of disease severity (mild versus cerebral malaria). Sera from 110 patients with confirmed severe cerebral malaria (CM) and 91 patients with mild malaria (MM) were analysed (mean age = 29 years) for total and subclass immunoglobulin (Ig)G to ME and total IgG to MSP1p19, MSP2, MSP3, MSP4 and MSP5 by enzyme-linked immunosorbent assay (ELISA). Functional antibody responses were evaluated using the antibody-dependent respiratory burst (ADRB) assay in a subset of sera. There was a trend towards higher IgG1 and IgG4 levels to ME in CM compared to MM; only ME IgM responses differed significantly between fatal and surviving CM patients. Increased prevalence of IgG to individual MSPs was found in the CM compared to the MM group, including significantly higher levels of IgG to MSP4 and MSP5 in the former. Sera from fatal (24·5%) versus surviving cases showed significantly lower IgG to MSP1p19 and MSP3 (P < 0·05). ADRB assay readouts correlated with high levels of anti-MSP IgG, and trended higher in sera from patients with surviving compared to fatal CM outcome (P = 0·07). These results document strong differential antibody responses to MSP antigens as targets of protective immunity against CM and in particular MSP1p19 and MSP3 as prognostic indicators.

[Frequency of micoalbuminuria during diabetes in Dakar (Senegal)]. / Frequence de la microalbuminurie au cours du diabète à Dakar (Sénégal).

Nephropathy is one of the complications occuring during diabetes diagnosed via microalbuminuria. From 1992 to 1999, five hundred and eighty seven (587) diabetic patients were recruited in groups A (n = 270) and B (n=317). Microalbuminuria was determined by immunonepheletry for A and immunoturbidimetry for B. The results pointed out respectively 15.5% and 20.19% pathological cases (NS). Considering the distribution of patients with microalbuminuria according to the type of diabetes there were 16.12% type 1 and 15.07% type 2 in group A against 22.60% and 18.13% in group B ; no stastically significant differences were observed either in the same group or from one group to another. These frequencies would reflect the situation in the nineties; they are lower than those encountered in other populations. Nevertheless monitoring is needed through a regular schedule to prevent nephropathy.