Acceptability of children's testing for HIV infection during routine care activities in the Pediatrics Department of Sourô Sanou Teaching Hospital in Bobo-Dioulasso (Burkina Faso)

Background

In order to contribute to the fight against the pediatric HIV infection, we have assessed, through a study in which we have systematically proposed to carry out children's testing, the rate of acceptability and the feasibility of children's HIV testing during the routine activities of the department. We have also analyzed the reasons for the acceptability or the refusal of the child's HIV testing by the accompanying person.

Detection of Memory B Activity Against a Therapeutic Protein in Treatment-Naïve Subjects

Bridging immunoassays commonly used to detect and characterize immunogenicity during biologic development do not provide direct information on the presence or development of a memory anti-drug antibody (ADA) response. In this study, a B cell ELISPOT assay method was used to evaluate pre-existing ADA for anti-TNFR1 domain antibody, GSK1995057, an experimental biologic in treatment naive subjects. This assay utilized a 7-day activation of PBMCs by a combination of GSK1995057 (antigen) and polyclonal stimulator followed by GSK1995057-specific ELISPOT for the enumeration of memory B cells that have differentiated into antibody secreting cells (ASC) in vitro. We demonstrated that GSK1995057-specific ASC were detectable in treatment-naïve subjects with pre-existing ADA; the frequency of drug-specific ASC was low and ranged from 1 to 10 spot forming units (SFU) per million cells. Interestingly, the frequency of drug-specific ASC correlated with the ADA level measured using an in vitro ADA assay. We further confirmed that the ASC originated from CD27⁺ memory B cells, not from CD27^?-naïve B cells. Our data demonstrated the utility of the B cell ELISPOT method in therapeutic protein immunogenicity evaluation, providing a novel way to confirm and characterize the cell population producing pre-existing ADA. This novel application of a B cell ELISPOT assay informs and characterizes immune memory activity regarding incidence and magnitude associated with a pre-existing ADA response.