Flow-cytometry analysis of (A) total CD19+ (left panel), CD19+CD1c+CD1a- (middle panel), and CD19+CD1c+CD1a+ (right panel) B-cells, (B) total CD19+CD138+ (left panel), CD19+CD138+CD1c+CD1a- (middle panel) and CD19+CD138+CD1c+CD1a+ (right panel) plasmablasts, (C) total CD19-CD138+ (left panel), CD19-CD138+CD1c+CD1a- (middle panel) and CD19-CD138+CD1c+CD1a+ (right panel) plasma cells, (D) total CD138+IgG+ (left panel), CD138+IgG+CD1c+CD1a- (middle panel) and CD138+IgG+CD1c+CD1a+ (right panel) plasmablasts and plasma cells. Cells were gated on live CD45+ CDKPAN- cells and were negative for CD3, CD56 and CD66. Relative frequencies were calculated vs total live CD45+CDKPAN- cells (A,B,C and D) left panels, vs total CD19+ B-cells (A) middle and right panels, vs total CD138+CD19+plamablasts (B) middle and right panels, vs total CD19-CD138+ plasma cells (C) middle and right panels, and vs CD138+IgG+ plasmablasts and plasma cells (D) middle and right panels. Data are presented as mean ± SD. Statistical significance of differences in the relative frequencies (%) were evaluated with Mann Whitney U test for pair-wise comparisons between HESNs and the two other groups. *p < 0.05, **p < 0.01 and ***p < 0.001. HIV, human immunodeficiency virus; CSWs, commercial sex workers; HESN, HIV Highly-Exposed Seronegative. SD, standard deviation.