HLA-G1 influences Ab responses and the cytokine environment in vivo. (A) Presence of specific antibodies against antigens derived from the human melanoma cell line (M8-pcDNA lysate) at days 6, 13, 20, and 27 after recovery of plasma as detected by slot-blot analysis. Data are from 1 representative experiment of 3. (B) Detection of specific Ab against melanoma Ag at day 27 by flow cytometry. Plasma dilutions were 1:500, 1:1000, and 1:5000. (C) Plasma concentrations of cytokines from naive mice or mice injected with tumor cells were quantified by ELISA. Green and red arrows indicate the cytokines with levels increased or decreased by HLA-G, respectively. M8-HLA-G1 tum⁺ indicates plasma collected at day 6; M8-HLA-G1 tum⁻, plasma collected at day 20.