Dendritic cell (DC) vaccination is an attractive approach to the treatment of patients with lymphoid tumors. To evaluate its feasibility, we have tested the functional properties of DC and T-lymphocytes in patients with treated and untreated chronic lymphocytic leukemia (CLL) and follicular lymphoma (FL). Healthy volunteers were used both as controls and as a source of cells for allogeneic mixed leukocyte reaction (MLR). In these reactions, dendritic cells from both untreated and treated patients were comparable to dendritic cells from healthy volunteers. In all the untreated patients studied, autologous dendritic cells promoted the survival and proliferation of both CD4 and CD8 lymphocytes (though the proliferation response was much better in the CD4 subset), whereas only 3 out of 5 treated patients were able to mount this response with CD4 lymphocytes and 4 out of 5 with CD8 lymphocytes. In 3 out of 5 untreated patients, pulsing of DCs with tetanus toxoid promoted a better CD4 response than was achieved with unpulsed DCs, while none of 5 treated patients had an additional response after pulsing with tetanus toxoid. None of patients studied, either treated or untreated, had a better CD8 response to pulsed DCs than to unpulsed ones. During CD4 lymphocyte proliferation, more CD4+CD25hi lymphocytes were generated in both treated and untreated patients than in healthy controls. Poor proliferation of cytotoxic cells and preferential proliferation of CD4+CD25hi T-regulatory cells in response to self and/or foreign antigens might be one of the mechanisms responsible for immunosuppression and impaired tumor surveillance in patients with lymphoid malignancies., R. Pytlík, P. Hofman, L. Kideryová, P. Červinková, P. Obrtlíková, J. Šálková, M. Trněný, P. Klener., and Obsahuje bibliografii a bibliografické odkazy
To evaluate the preclinical efficacy and safety of human mesenchymal stem cells (hMSC) rapidly expanded in growth medium for clinical use with human se rum and recombinant growth factors, we conducted a controlled, randomized trial of plasma clots with hMSC vs. plasma clots only in critical segmental femoral defects in rnu/rnu immunodeficient rats. X-ray, microCT and histomorphometrical evaluation were pe rformed at 8 and 16 weeks. MSC were obtained from healthy volunteers and patients with lymphoid malignancy. Human MSC survived in the defect for the entire duration of the trial. MSC from healthy volunteers, in contrast to hMSC from cancer patients, significantly improved bone healing at 8, but not 16 weeks. However, at 16 weeks, hMSC significantly improved vasculogenesis in residual defect. We conclude that hMSC from healthy donors significantly contributed to the healing of bone defects at 8 weeks and to the vascularisation of residual connective tissue for up to 16 weeks. We found the administration of hMSC to be safe, as no adverse reaction to human cells at the site of implantation and no evidence of migration of hMSC to distant organs was detected., R. Pytlík, C. Rentsch, T. Soukup, L. Novotný, B. Rentsch, V. Kanderová, H. Rychtrmocová, M. Kalmárová, D. Stehlík, M. Trněný, O. Slanař., and Obsahuje bibliografii