Decreased frequency of CD300a⁺ B cells in HIV-infected patients. PBMCs from healthy donors (HD), HIV-aviremic (HIV-AVIR) patients, and HIV-viremic (HIV-VIR) patients were labeled with anti-CD10, anti-CD19, anti-CD20, anti-CD21, anti-CD27, and anti-CD300a mAb. The lymphocyte gate was determined according to the forward and side scatter parameters. (A) The percentage of CD300a⁺ cells in the CD19⁺ gate (B cells) was determined. Each symbol represents a different donor. (B) The percentage of CD300a⁺ cells among CD21⁺ B cells (left panel) and CD21⁻ B cells (right panel) was determined.