Cellular immunity to transitional cell carcinoma of the urinary bladder. III. Effects of hydrostatic pressure therapy

Cytotoxicity in vitro of blood lymphocytes from bladder cancer patients and controls to allogeneic or autologous tumor cells derived from established cell lines or short-term cultures

Blood lymphocytes from small groups of patients with transitional-cell carcinoma of the urinary bladder (TCC), clinical controls (CC) or healthy donors (HD) were tested for cytotoxicity in vitro by a 51Cr-release assay. The target cells were either from TCC or control tissue (long-term cultures) or were from short-term TCC cultures, kept in vitro for 10-20 transfer generations. When tested with allogeneic target cells from long-term cultures, TCC patients' lymphocytes tended to be more cytotoxic to TCC targets than to control targets. For the control lymphocytes this was not seen. A large proportion but not all of the cytotoxicity to these target cells was due to immunoglobulin-dependent cellular reactions, probably mediated by natural and disease-related antibodies of the lymphocyte donors, since it was significantly inhibited by Fab-fragments of rabbit antibodies to human immunoglobulin. Moreover, it was, to a large extent, mediated by lymphocytes with Fc-receptors for IgG. For seven of the TCC target cell cultures (two long-term and five short-term) autologous lymphocytes were also available for testing. While two patients were non-reactive to their own tumor cells, five reacted strongly in the autologous combinations. These autologous reactions were immunoglobulin-independent and were mediated by Fc-receptor-negative effector cells. In some instances, autologous cytotoxicity was accompanied by similar reactions to some of the allogeneic TCC targets but not to the allogeneic non-TCC control targets. On the basis of available information on HLA antigens in this material, the pattern of cross-reactions suggests that the cytotoxicity encountered in the autologous and in some of the allogeneic TCC-combinations may be the expression of antibody-independnet but specific CTL-mediated reactions, regulated by HLA. However, at the present stage of the investigation, other mechanisms must also be considered since the target cells from short-term TCC cultures were sometimes lysed by control lymphocytes in immunoglobulin-independent reactions. Whatever the explanation, the results show that the cytotoxicity observed in the in vitro systems is usually the net result of several different types of reaction. Which effector cell types and which mechanism of recognition will predominate in a given lymphocyte/target cell combination is greatly influenced by the nature and origin of the target cells used.

Commentary on the immunobiology of bladder cancer

This review is an attempt to integrate the conflicting studies that constitute the literature on immunobiology of bladder cancer and to indicate areas that need further investigation. It is clear that immune reactivity directed at antigens expressed on bladder cancer cells and general host immunologic competence decline with progressive tumor growth. This immunodepression correlates with patient prognosis, even within a given stage of disease. The mechanisms underlying this decline in host immune reactivity are poorly understood. A better understanding of these mechanisms may provide fundamental insight into the host-tumor relationship that possibly could be exploited for preventive, diagnostic and therapeutic purposes.

A 51chromium isotope release assay for detecting cytotoxicity to human bladder carcinoma

A 51chromium isotope release assay is described for measuring in vitro cytotoxicity reactions against allogenetic target cells. Lymphoid cells from some patients with localized transitional cell carcinoma (TCC) were shown to selectively lyse targets derived from two long-term cell lines of TCC. The effector cells in this reaction did not form E rosettes. Cytotoxicity was successfully recovered after cryopreservation.

A cell line (SCABER) derived from squamous cell carcinoma of the human urinary bladder

An established cell line derived from a documented squamous cell carcinoma of human urinary bladder is described. The cultured cells retained the characteristic morphology of the tumor of origin for 40 in vitro passages. Numerous desmosomes were found between cultured cells. Chromosome analysis showed hypotetraploidy with no obvious modal number, while distinctive marker chromosomes and a male karyotype were present.