Assessment and characterization of the cytolytic T lymphocyte response against Epstein–Barr virus in patients with non-Hodgkin’s lymphoma after autologous peripheral blood stem cell transplantation

Abstract

Summary:The cytolytic T lymphocyte (CTL) response has often been used to assess the reconstitution of T cell function after allogeneic or autologous bone marrow transplantation (BMT). Less is known, however, about the reconstitution of the CTL response after peripheral blood stem cell transplantation (PBSCT). Therefore, we investigated the CTL response against Epstein-Barr virus (EBV) of patients undergoing autologous PBSCT. CTLs of six patients with relapsed non-Hodgkin's lymphoma and multiple myeloma were established before and at different times after PBSCT by in vitro stimulation of peripheral blood lymphocytes with autologous EBVtransformed lymphoblastoid cell lines (LCLs). The efficiency of T cell priming by LCLs was assessed at the time of initiation of CTL lines; the proliferative response was strongly reduced during the first 4 months and increased 5 months or more following PBSCT. Cytolytic activity was measured after three or four restimulations of CTLs. All patients investigated had a detectable EBV-specific CTL response which was poor during the first weeks after transplantation, accompanied by a strong non-MHC-restricted cytotoxic activity and a high proportion of CD56-positive T cells. Five or more months after PBSCT, a specific CTL response against EBV was seen which was similar to the situation prior to PBSCT, while the unspecific cytotoxic response decreased. Blocking experiments with monoclonal anti-CD3, anti-CD8 or anti-MHC I antibodies resulted in substantial inhibition of autologous LCL lysis, whereas anti-CD4 or anti-MHC II antibodies had no effect. Finally, autologous PHA blasts of a patient with the HLA haplotype A1/9+, B5/8+, Cw4/7+, were loaded with various EBNA-derived nonapeptides known to be presented by HLA B8 or A11, and exposed to autologous, EBV-directed In the last few years, autologous peripheral blood stem cell transplantation (PBSCT) has been established as a standard treatment for relapsed aggressive non-Hodgkin's lymphoma and has proven advantageous when compared with autologous or allogeneic bone marrow transplantation (BMT). 1-5 However, in contrast to autologous or allogeneic BMT, little information is available concerning the reconstitution of the immune system following autologous peripheral blood stem cell transplantation (PBSCT). As after BMT, the CD4/CD8 ratio seems to be inversed after PBSCT, but lymphocyte subpopulations and functions recover more rapidly, including the proliferative response to mitogens and the cytotoxic activity of lymphocytes after stimulation with high-dose IL-2 (lymphocyte-activated killer cells, LAK). [6][7][8][9][10] Previous investigations mainly examined non-specific lymphocyte functions in patients undergoing autologous PBSCT and the reconstitution of the antigen-specific cytolytic T lymphocyte (CTL) response has not been evaluated so far. Therefore, we examined the CTL response of these patients to Epstein-Barr virus (EBV), a widespread lymphotropic herpes virus. Most people are infected with EBV by adulthood, and the life-long persist...

Reconstitution of the cellular immune response after autologous peripheral blood stem cell transplantation in patients with non‐Hodgkin's lymphoma

“…Indeed, the present study showed a strong lysis of K562 cells in some patients, providing evidence for the contribution of MHC-unrestricted cytotoxicity. Immunophenotyping con®rmed the existence of CD3/CD56 cells after autologous PBSCT, and these cells may have acted as non-MHC-restricted effector cells in our experiments, as has been shown for a subset of CD3 lymphocytes with NK celllike properties (Falk et al, 1995;Nossner et al, 1996;Mingari et al, 1998). As it is known that certain viruses or tumours may escape from the speci®c CTL response in vivo, these unspeci®c effector mechanisms may play a very important role in host defence against viral pathogens or tumour cells (Maudsley & Pound, 1991;Schendel et al, 1997).…”

“…We have shown previously that, in patients with haematological malignancies who underwent autologous PBSCT, the cytolytic activity directed against EBV‐immortalized B‐lymphoblastoid cell lines (LCL) could be characterized as similar to that of healthy persons. It is directed against EBV‐derived peptides and MHC I restricted; the main effector cells are CD3+/CD8+ ( Nolte et al ., 1998 ).…”

Successful treatment of post-transplant lymphoproliferative disorder in autologous blood stem cell transplant recipients

“…2 Risk factors have not been defined for ASCT, but authors have speculated on the role of T cell depleting the autograft, concurrent CMV infection, and impaired cytolytic T cell response specifically to EBV. 3,7 In the autologous bone marrow patients with PTLD reported previously, three were in the context of T cell-depleted grafts, and one in a B celldepleted graft. 4,[8][9][10] One patient was also on prednisone as part of his treatment for PCP and CMV pneumonitis.…”

Combination of Intensive Chemotherapy and Anticancer Vaccines in the Treatment of Human Malignancies: The Hematological Experience

“…Defective proliferation of both CD4 + and CD8 + T cells in response to antiCD3 and antiCD2 persists for at least for 2–4 months, and this seems to be caused by defective IL-2 responsiveness [64, 66]. Furthermore, the specific cytotoxic T cell response against Epstein-Barr virus is significantly impaired for 2–5 months [67], whereas the frequency of circulating cytokine-secreting T helper cells and IL-2 responding T cells can be decreased for up to 5 years posttransplant [68]. …”