Malaria vaccine candidate: design of a multivalent subunit α-helical coiled coil poly-epitope

A new strategy for the rapid identification of new malaria antigens based on protein structural motifs was previously described. We identified and evaluated the malaria vaccine potential of fragments of several malaria antigens containing α-helical coiled coil protein motifs. By taking advantage of the relatively short size of these structural fragments, we constructed different poly-epitopes in which 3 or 4 of these segments were joined together via a non-immunogenic linker. Only peptides that are targets of human antibodies with anti-parasite in vitro biological activities were incorporated. One of the constructs, P181, was well recognized by sera and peripheral blood mononuclear cells (PBMC) of adults living in malaria-endemic areas. Affinity purified antigen-specific human antibodies and sera from P181-immunized mice recognised native proteins on malaria-infected erythrocytes in both immunofluorescence and western blot assays. In addition, specific antibodies inhibited parasite development in an antibody dependent cellular inhibition (ADCI) assay. Naturally induced antigen-specific human antibodies were at high titers and associated with clinical protection from malaria in longitudinal follow-up studies in Senegal.     

Comparison of INNO-LiPA HPV Genotyping v2 with PCR product subcloning and sequencing for identification of genital human papillomavirus genotypes in African women

The performance characteristics of the INNO-LiPA Genotyping v2 test for human papillomavirus (HPV) identification were assessed by comparing results with those obtained by PCR product sequencing after subcloning, in genital samples from 20 highly sexually exposed African women. The INNO-LiPA HPV Genotyping v2 test identified more HPV types than subcloning/sequencing (56 versus 37, respectively). Overall, 86.5% (32/37) of the HPV types identified by subcloning/sequencing were identified by the INNO-LiPA HPV Genotyping v2 test, whereas 57.1% (32/56) of the HPV types identified by the INNO-LiPA HPV Genotyping v2 test were identified by subcloning/sequencing. Of the 20 clinical samples tested, 7 had identical types detected under both methods and a further 11 had more types detected under INNO-LiPA HPV Genotyping v2 than subcloning/sequencing. Of the remaining two samples, the same number of types were detected under both methods, but different types were detected. INNO-LiPA HPV Genotyping v2 test appears as a valid method for identifying HPV subtypes in women with multiple HPV infection.     

Validity of impedance-based predictions of total body water as measured by 2H dilution in African HIV/AIDS outpatients

Measurements of body composition are crucial in identifying HIV-infected patients at risk of malnutrition. No information is available on the validity of indirect body composition methods in African HIV-infected outpatients. Our first aim was to test the validity of fifteen published equations, developed in whites, African-Americans and/or Africans who were or not HIV-infected, for predicting total body water (TBW) from bioelectrical impedance analysis (BIA) in HIV-infected patients. The second aim was to develop specific predictive equations. Thirty-four HIV-infected patients without antiretroviral treatment and oedema at the beginning of the study (age 39 (SD 7) years, BMI 18.7 (SD3.7) kg/m2, TBW 30.4 (SD7.2) kg) were measured at inclusion then 3 and 6 months later. In the resulting eighty-eight measurements, we compared TBW values predicted from BIA to those measured by 2H dilution. Range of bias values was 0.1-4.3 kg, and errors showed acceptable values (2.2-3.4 kg) for fourteen equations and a high value (10.4) for one equation. Two equations developed in non-HIV-infected subjects showed non-significant bias and could be used in African HIV-infected patients. In the other cases, poor agreement indicated a lack of validity. Specific equations developed from our sample showed a higher precision of TBW prediction when using resistance at 1000 kHz (1.7 kg) than at 50 kHz (2.3 kg), this latter precision being similar to that of the valid published equations (2.3 and 2.8 kg). The valid published or developed predictive equations should be cross-validated in large independent samples of African HIV-infected patients.