[Proliferation and anti-tumor activity of lymphocytes and their effect on normal phenotype of autologous bone marrow hematopoietic cells in patients with paroxysmal nocturnal hemoglobinuria].

There is a hypothesis that paroxysmal nocturnal hemoglobinuria (PNH) hematopoitic stem cells are resistant to the cytotoxic effect of T cells because they lack glycosylphosphatidylinositol (GPI)-linked proteins. The aim of this study is to investigate proliferation and anti-tumor activity of lymphocytes in patients with PNH, and also to assay the effect on normal cell (CD59(+)) phenotype in bone marrow of PNH patient by autologous lymphocytes in vitro. MTT assay for detection of lymphocytes proliferation and its anti-tumor effect was driven to delineate T cell reactive function. The CD34(-) and CD34(+) bone marrow cells (selected by means of immunomagnetic method) as well as unsorted marrow cells in PNH patients were cultured together with autologous CD59(+) or CD59(-) lymphocytes, their cultured supernatant, extrinsic IFN-gamma and IL-2 in a liquid culture system. CD59(+) cells were counted by flow cytometry after 10 day culture in vitro. The results showed that there were no differences in the proliferation ability of lymphocytes between each group: controls 1.42 +/- 0.46, unsorted PNH lymphocytes 1.40 +/- 0.35, CD59(-) 1.30 +/- 0.40, and CD59(+) PNH lymphocytes 1.40 +/- 0.42. Anti-tumor effect of lymphocytes declined in PNH patients when compared with control [(50.00 +/- 28.67)% vs. (76.13 +/- 10.15)%]. The proportion of CD59(+) cells diminished significantly after culture with autologous lymphocytes, their supernatant, extrinsic IFN-gamma or IL-2 (P < 0.01) in groups of unsorted, CD34(+) and CD34(-) bone marrow cells. No significant difference was found between groups of CD59(-) and CD59(+) lymphocytes, or CD34(-) and CD34(+) marrow cells. It is concluded that turbulences of immune regulations may be involved in pathogenesis of PNH.