RESUMEN
BACKGROUND AIMS: The impact of chronic lymphatic leukemia (CLL) tumor burden on the autologous immune system has already been demonstrated. This study attempted to elucidate the molecular mechanisms underlying T-cell immunologic deficiencies in CLL. METHODS: Freshly isolated CD3(+) T cells from patients with a diagnosis of CLL and healthy donors were analyzed by gene expression profiling. Activated T cells from 20 patients with CLL were tested in vitro for cytotoxicity against mutated and unmutated autologous B cells and DAUDI, K562 and P815 cell lines. To investigate T-cell mediated cytotoxicity in vivo, we co-transplanted OKT3-activated T lymphocytes and autologous B-cell CLL (B-CLL) cells into NOD/SCID mice. RESULTS: Gene expression profiles of peripheral blood T cells from B-CLL patients showed 25 down-regulated, and 31 up-regulated, genes that were mainly involved in cell differentiation, proliferation, survival, apoptosis, cytoskeleton formation, vesicle trafficking and T-cell activation. After culture, the T-cell count remained unchanged, CD8 cells expanded more than CD4 and a cytotoxicity index >30% was present in 5/20 patients. Cytotoxicity against B autologous leukemic cells did not correlate with B-cell mutational status. Only activated T cells exerting cytotoxicity against autologous leukemic B cells prevented CLL in a human-mouse chimera. CONCLUSIONS: This study indicates that patients with CLL are affected by a partial immunologic defect that might be somewhat susceptible to repair. This study identifies the molecular pathways underlying T-cell deficiencies in CLL and shows that cytotoxic T-cell functions against autologous B-CLL can be rebuilt at least in part in vitro and in vivo.
Asunto(s)
Citotoxicidad Inmunológica/inmunología , Leucemia Linfocítica Crónica de Células B/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/inmunología , Animales , Línea Celular Tumoral , Proliferación Celular , Citotoxicidad Inmunológica/efectos de los fármacos , Citotoxicidad Inmunológica/genética , Regulación hacia Abajo/genética , Regulación hacia Abajo/fisiología , Perfilación de la Expresión Génica , Reordenamiento Génico de Linfocito B/genética , Reordenamiento Génico de Linfocito B/inmunología , Humanos , Factores Inmunológicos/farmacología , Interleucina-2/farmacología , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/metabolismo , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/genética , Activación de Linfocitos/fisiología , Ratones , Ratones SCID , Muromonab-CD3/farmacología , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Hipermutación Somática de Inmunoglobulina/genética , Hipermutación Somática de Inmunoglobulina/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Regulación hacia Arriba/genética , Regulación hacia Arriba/fisiologíaRESUMEN
Although adoptive transfer of donor lymphocytes protects from infections and relapse after allogeneic hematopoietic stem cell transplantation in both mice and in men, it is associated with a high risk of graft versus host disease (GvHD) which rises with HLA mismatching and the number of T lymphocytes that are infused. Elimination/reduction of alloreactive donor T lymphocytes is an appealing approach and several strategies have been proposed. Here we describe generation of anti-3rd party T lymphocytes under conditions of IL-2 deprivation and their effects in a pre-clinical murine model. Our results clearly indicated that anti-3rd party T lymphocytes generated on a large scale by means of IL-2 deprivation maintain a broad T cell repertoire, do not proliferate in a mixed lymphocyte reaction and do not cause GvHD in NOD-SCID mice. These anti-3rd party lymphocytes contain a large adaptive T regulatory cell subset which might contribute to in vitro and in vivo immune modulation.