The Reed-Sternberg cell/lymphocyte rosette. I. Properties of rosettes formed between Hodgkin's cell lines and allogeneic lymphocytes.

The properties of rosettes formed between the Hodgkin's cell lines, L428 and L591, and allogeneic peripheral blood mononuclear cell populations have been investigated. Immunocytochemical analysis showed that the majority of adherent cells were T-cells of both the CD4 and CD8 subsets. Only relatively few B-cells and monocytes were seen to adhere. However, when peripheral blood mononuclear cell populations were fractionated, it was found that monocytes were as good as T-cells at forming rosettes with both L428 and L591, though B-cells were shown to be poor at forming such associations. Treatment of both L428 and L591 with neuraminidase resulted in a significant reduction (P less than 0.01) in the mean number of adherent lymphocytes and in the numbers of Hodgkin's tumour cells which formed rosettes. Smaller, less significant effects were observed for Cytochalasin B and trypsin. EDTA (10(-2) M) at pH 7.2 had no significant effect on rosetting for L428 or L591. Adherence of allogeneic lymphocytes to L428 or L591 was pH dependent but did not appear to correlate with cell surface charge. Treatment of L428 cells with Fab fragments prepared from the IgG fraction of a hyperimmune rabbit anti-L428 antiserum, significantly (P less than 0.05) inhibited the adherence of allogeneic lymphocytes, but only when used at high concentration. The binding requirements of the Hodgkin's cell lines with allogeneic peripheral blood lymphocytes, as described in this study, appear to be quite different from those described for freshly isolated Hodgkin's tumour cells with autologous intratumoral lymphocytes. This suggests that the two phenomena may be unrelated. There would appear to be an absolute requirement for cell surface sialic acid for allogeneic lymphocyte attachment to the HD cell lines. This might suggest that the receptor-ligand system involved contains sialic acid as an integral part of the cell surface receptor structure involved in recognition of the appropriate ligand.