Impairment of pneumococcal antigen specific isotype-switched Igg memory B-cell immunity in HIV infected Malawian adults.
Pneumococcal disease is associated with a particularly high morbidity and mortality amongst adults in HIV endemic countries. Our previous findings implicating a B-cell defect in HIV-infected children from the same population led us to comprehensively characterize B-cell subsets in minimally symptomatic HIV-infected Malawian adults and investigate the isotype-switched IgG memory B-cell immune response to the pneumococcus. We show that similar to vertically acquired HIV-infected Malawian children, horizontally acquired HIV infection in these adults is associated with IgM memory B-cell (CD19(+) CD27(+) IgM(+) IgD(+)) depletion, B-cell activation and impairment of specific IgG B-cell memory to a range of pneumococcal proteins. Our data suggest that HIV infection affects both T-cell independent and T-cell dependent B-cell maturation, potentially leading to impairment of humoral responses to extracellular pathogens such as the pneumococcus, and thus leaving this population susceptible to invasive disease.
School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom ; Malawi Liverpool Wellcome Trust Clinical Research Programme, University of Malawi College of Medicine, Blantyre, Malawi.
Oluwadamilola H
OH
Iwajomo
Adam
A
Finn
Abiodun D
AD
Ogunniyi
Neil A
NA
Williams
Robert S
RS
Heyderman
D000328:Adult; D000942:Antigens, Bacterial / Q000097:blood* / Q000276:immunology; D016175:B-Lymphocyte Subsets / Q000276:immunology / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D006678:HIV / Q000276:immunology; D015658:HIV Infections / Q000097:blood / Q000150:complications / Q000276:immunology* / Q000821:virology; D006801:Humans; D017578:Immunoglobulin Class Switching; D007074:Immunoglobulin G / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood*; D007156:Immunologic Memory; D008213:Lymphocyte Activation; D008212:Lymphocyte Depletion; D008295:Malawi; D008297:Male; D011018:Pneumonia, Pneumococcal / Q000097:blood / Q000150:complications / Q000276:immunology* / Q000382:microbiology; D013296:Streptococcus pneumoniae / Q000276:immunology*
D000942:Antigens, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M