TIME-COURSE OF THE RECOVERY OF CELLULAR IMMUNE FUNCTION AFTER HIGH-DOSE CHEMOTHERAPY AND PERIPHERAL-BLOOD PROGENITOR-CELL TRANSPLANTATION FOR HIGH-GRADE NON-HODGKINS-LYMPHOMA

Chemotherapy induces high remission rates in high-grade lymphoma. Howe ver relapse remains a major problem, One approach to this is myeloabla tive chemotherapy with transplantation of autologous bone marrow or pe ripheral blood progenitor cells (PBPC). Immunological mechanisms have been suggested to play a role in the prevention of relapse after trans plantation. We investigated the recovery of cellular immune functions after high-dose chemotherapy and PBPC transplantation in 5 patients wi th high grade non-Hodgkin's lymphoma, All patients showed rapid recons titution of natural killer (NK) and inducible lymphokine-activated kil ler (LAK)-activity 10-14 days after transplantation. Four of 5 patient s showed higher levels of LAK-generation in the post-transplant period compared with levels prior to myeloablative treatment, Absolute lymph ocyte counts in peripheral blood reached 1.0 x 10(9)/l between days 10 and 13 with a predominance of CD8(+) cells and an inversion of the CD 4/CD8 ratio, Four of 5 patients had a transient increase in CD56(+) an d CD16(+) cell counts post-transplant. No change in the proportion of CD25(+) cells was noted, These results show that PBPC transplantation leads to a rapid recovery of cellular immune functions after myeloabla tive chemotherapy and provides evidence for an increased presence of L AK precursor cells early in the post-transplant period which can be ac tivated by IL-2 to exert high levels of cytotoxicity.