Cancer patients' lymphocytes contain CD3+ CD4+ cells that proliferate in response to autologous tumor cells in the presence of exogenous low-dose interleukin-2 and autologous accessory cells

Clonal analysis of peripheral blood lymphocytes from three patients with advanced neuroblastoma receiving recombinant interleukin-2 and interferon alpha

In this study we have investigated, at the population and the clonal levels, the immunophenotypes and the non-specific cytotoxic functions of peripheral blood lymphocytes from three stage IV neuroblastoma patients receiving treatment with recombinant interleukin-2 (IL-2) and interferon alpha (IFN alpha). Both IL-2 alone and the combination of IL-2 and IFN alpha caused an in vivo expansion of CD56+, CD3- NK cells most of which expressed the p75 molecule, i.e. the beta chain of the IL-2 receptor. Peripheral blood mononuclear cells (PBMC), drawn after treatment, displayed an increased NK activity, but no lymphokine-activated killer (LAK) activity. However, the subsequent in vitro culture of PBMC with high-dose IL-2 induced the generation of a potent LAK activity, which was mediated by an expanded population of CD3+, CD8+ T cells. Finally lymphocytes that had been isolated after cytokine therapy were cloned, in the presence of low-dose phytohemagglutin, immediately or following culture with IL-2. Clones derived from LAK cells expanded in vitro had predominantly a CD3+, CD8+ immunophenotype, whereas those raised from freshly separated lymphocytes were either CD3+, CD4+ or CD3+, CD8+ in equal proportions. Most of the above clones were poorly or not at all cytolytic against NK-sensitive or NK-resistant targets. In contrast, the few NK clones obtained (CD3-, CD56+) lysed all targets with high efficiency.

Human allogeneic melanoma-reactive T-helper lymphocyte clones: functional analysis of lymphocyte-melanoma interactions

Lymphocyte clones were isolated from CD4+ peripheral-blood lymphocytes (PBL) of melanoma (Me) patient 9923 (HLA-DR7, DQw2, w6), co-cultured for 30 days with autologous accessory cells, allogeneic Me (Me 1811) (HLA-DR7, DQw1, w2), IL-1 beta (2 U/ml) and IL-2 (15 IU/ml). The 55 clones tested displayed a CD3+, CD4+, CD8-, T-cell receptor (TCR) alpha/beta+, gamma/delta- phenotype. Twenty clones were assayed for proliferation in the presence of Me 1811 and B-lymphoblastoid cell line (LCL) 1811, both expressing HLA-class-I and -II (DR7 and DQw2 shared with patient 9923), intercellular adhesion molecule-1 (ICAM-1) and lymphocyte-function-associated antigen-3 (LFA-3) molecules. Eight clones were found to be reactive to Me 1811 but not to LCL 1811. Specificity analysis of these 8 clones revealed that each of them proliferated only to Me 1811, not to other 14 Me and 12 different LCL, suggesting recognition of melanoma-associated antigen (MAA) expressed on the stimulating Me. One clone (103) was analyzed in more detail. A wider specificity analysis showed that it reacted to Me 1811 but not to 10 other Me expressing or not HLA-DR7, 5 normal melanocyte cultures (2 of them typing HLA-DR7-positive when exposed to interferon-gamma--IFN-gamma), 4 tumors other than Me and 20 different LCL. Clones did not show proliferation in the presence of autologous Me cells. Clone proliferation in response to Me 1811 was significantly inhibited by monoclonal antibodies (MAbs) directed to CD3, TCR alpha/beta, TCR beta chain V12, CD4 and HLA-DR. Moreover, following stimulation with Me 1811, clone 103 showed increased surface expression of CD25 (IL-2 receptor) and CD71 (transferrin receptor) and produced significant amounts of IL-2 and IFN-gamma. The supernatant taken from co-culture of clone 103 with Me 1811 augmented the cytotoxicity of PBL 9923 and other allogeneic PBL against K562 and Me 1811. Thus, the lymphocyte clone 103 is a CD4+ Th clone which uses its CD3/TCR alpha/beta complex to recognize an MAA in conjunction with HLA-DR7. Availability of this type of reagent may prove useful to identify and characterize MAA recognized by T lymphocytes.