Lymphocyte populations in autopsy bone marrow sections from recipients of allogeneic marrow and non-transplant sudden death cases.

Femoral marrow, obtained at autopsy, was stained using immunohistological techniques, for T (CD2+) cells, B (CD19+) cells, helper/inducer (CD4+) T cells, suppressor/cytotoxic (CD8+) T cells and natural killer (HNK1+) cells. The numbers present in 13 recipients of allogeneic marrow, 14 to 140 days after transplantation, were compared with those in marrows from nine subjects with no haematological or malignant conditions. In marrow sections from non-transplant subjects, approximately 8% nucleated cells were CD2+ with CD4+ and CD8+ cells present in nearly equal numbers; 1-3% were CD19+ and generally less than 1% HNK1+. The percentages of CD19+ and CD4+ cells were significantly reduced after bone marrow transplantation but, if a correction factor for marrow cellularity was introduced, then CD2+ and CD8+ cell values were also low. The findings were compared with the number of cells transplanted, the time after transplantation, presence of graft-versus-host disease or infection and peripheral blood white cell count, but no correlation was found.