Productive infection of normal CD40-activated human B lymphocytes by HIV-1

Replication kinetics and cell tropism of an immunosuppressive feline leukaemia virus

“…Interestingly, FIV tropism studies also suggest that CD4 cells harbour a higher provirus load early in infection and that B cells may become a major reservoir in chronically infected cats (Dean et al, 1993;English et al, 1993). While B cells can be infected by human immunodeficiency virus (HIV; Poulin et aL, 1994), this is thought to be a very minor host cell population overall. Thus, among a broad array of retroviruses, CD4 + T lymphocytes appear to be a frequent early target cell whereas B cells are subsequent reservoirs for some retroviruses.…”

Tyrosine kinase and cAMP‐dependent protein kinase activities in CD40‐activated human B lymphocytes

“…In addition, we previously demonstrated that proliferating CD40-stimulated human B lymphocytes are permissive to productive infection by HIV-1 [36], signifying that the HIV-1 LTR promoter is active under these conditions. EMSA performed using nuclear extracts from CD40-stimulated B cells and NF-xB binding sequences from HIV-1 LTR gave results similar to those obtained using the immunoglobulin x light chain sequence (data not shown).…”

Characterization of the CD154-Positive and CD40-Positive Cellular Subsets Required for Pathogenesis in Retrovirus-Induced Murine Immunodeficiency

“…Particularly relevant to the present study, several recent reports have defined CD154-CD40 interactions that may be important to HIV infectivity and/or pathogenesis. In a study by Poulin et al (42), human B lymphocytes activated in vitro with murine cell surface-presented CD154 in the presence of interleukin-4 became infectable by HIV type 1 (HIV-1). When such infected B cells were cocultured with an HIV-1-susceptible CD4 ϩ T-cell line, B-T cell fusion and syncytium formation led to direct infection of the T cells (42).…”

“…In a study by Poulin et al (42), human B lymphocytes activated in vitro with murine cell surface-presented CD154 in the presence of interleukin-4 became infectable by HIV type 1 (HIV-1). When such infected B cells were cocultured with an HIV-1-susceptible CD4 ϩ T-cell line, B-T cell fusion and syncytium formation led to direct infection of the T cells (42). In a follow-up report, it was further found that culturing freshly isolated B lymphocytes with soluble oligomeric CD154 plus interleukin-4 upregulated B-cell CD4 and CXCR4 receptor expression, with subsequent greatly increased susceptibility to infection by T-cell-tropic and dualtropic strains of HIV but not by macrophagetropic strains.…”