Immunological Enhancement of Tumor Growth by Syngeneic Thymus-Derived Lymphocytes

Induction of resistance or enhancement to a transplantable murine plasmacytoma by transfer of non-immune leucocytes

“…In effect, a considerable body of evidence shows that the immune defect in neonates can be repaired by adult macrophages or their precursors (Argyris, 1968;Blaese, 1975 The increased frequency of tumours observed in the newborn recipients after the transfer of low numbers of spleen, neutrophils or thymus cells may be the result of a mechanism of tumour immunostimulation as proposed by Prehn (1972), Prehn and Lappe (1971). An apparently similar block or enhancement exerted by different cell numbers has been reported in several systems, both in vitro (Prehn, 1972;Klein, 1972;Fidler, 1973;Fidler, Brodey and Bech-Nielsen, 1974;Kall and Hellstrom, 1975;Nathan and Terry, 1975) and in vivo (Belayev and Gruntenko, 1972;Fidler, 1974;Carnaud et al, 1974;Umiel and Trainin, 1974). However, in the present case, the effect of the transferred leucocyte populations may not be merely the result of direct interaction of leucocytes on tumour cells, since the inoculation of leucocytes was made 24 h prior to tumour inoculation and by a different route from the neoplastic cells.…”

“…Although cellular-mediated resistance to tumour development in vivo and cellmediated lysis of neoplastic cells in vitro are general findings in several human and experimental host-tumour systems (for a review see Hellstrom and Hellstrom, 1974) there are several other situations in which cellular-mediated enhancement of tumour cell growth appears to take place both in vitro (Prehn, 1972;Klein, 1972;Fidler, 1973;Fidler, Brodey and BechNielsen, 1974;Kall and Hellstrom, 1975;Nathan and Terry, 1975) and in vivo (Belayev and Gruntenko, 1972;Fidler, 1974;Carnaud et al, 1974;Umiel and Trainin, 1974). These contrasting findings can be interpreted by the theory, advanced by Prehn, that the effect of immunity might be biphasic, that is, a mild incipient immune response may be stimulatory to tumour growth but a strong one can be inhibitory (Prehn and Lappe, 1971).…”

Enhancing and inhibiting effects of spleen cells from tumour-bearing mice on growth of virus-induced primary sarcoma

“…This has been demonstrated in transplanted tumour systems (Ilfeld et al, 1973;Umiel and Trainin, 1974;Small and Trainin, 1976;Gabizon et al, 1976). Although the failure to enhance antigenically distinct syngeneic tumour cells (MCA-15B) may imply that the mechanism of enhancement in our system is a specific one, it is possible that this failure resulted from the nature of the tumour cells.…”

“…However, despite these immune responses observed in vitro, most tumours grow progressively to kill the host animal. Hypotheses which have been proposed to explain the discrepancies between in vitro and in vivo results include; (i) the presence of specific serum blocking factors in tumour-bearing mice (Hellstrom and Hellstrom, 1969;Hellstrom and Hellstrom, 1970;Sjogren and HellstrOm, 1971;Jurin and Suit, 1974;Kilburn et al, 1976;McMaster et at., 1977); (ii) suppressor-cell activity against specific immune lymphocytes (Glaser et at., 1975;Fujimoto et al, 1976aFujimoto et al, , 1976b or non-specific lymphocytes (Kirchner et al, 1974;Gorczynski, 1974;Kirchner et al, 1975); and (iii) cell-mediated enhancement of tumour growth (Ilfeld et al, 1973;Umiel and Trainin, 1974;Small and Trainin, 1976;Gabizon et al, 1976).…”

Enhancement of growth of a radiation-induced lymphoma by T cells from normal mice

“…The growth of the 3LL tumour of spontaneous origin and of some chemically induced fibrosarcomas was enhanced by lymphocytes of tumour-bearing mice (Umiel & Trainin, 1974;Gabizon et al, 1976;Manor et al, 1976). In addition, tumour-enhancing lymphocytes from mice bearing a chemically induced fibrosarcoma were found to abolish the activity of tumour-inhibiting lymphocytes when mixed together .…”