Response of tumour-related and normal lymphocytes to antigens on fibroblasts from embryos of varying age

Abstract

Summary.-The in vitro cytotoxic immune response of spleen lymphocytes from primiparous and tumour-related mice to embryonic cells from embryos of varying age and tumour cells has been investigated. The results indicate that lymphocytes from both primiparous and tumour-related (i.e., tumour-bearing or tumour-excised) animals give a response which is greater than that from cells from control mice ("virgin cells"). Moreover, in this putative anamnestic response the immune cells detect antigenic differences in the cell populations of embryos of varying age, which are not as readily demonstrable when cytotoxicity is derived from virgin cells. As a further indication of the in vivo priming to embryo-associated antigens, the data show that the precursors of cytotoxic cells apparently undergo a blastogenic response in the presence of embryo antigen, and revert to small quiescent cells when antigen is removed, in a way entirely analogous to that described for reactivity of mixed leucocyte cultures to antigens of the major histocompatibility complex. Finally, it seems that in animals immediately after removal of embryonic antigen (and to a lesser degree in virgin or late-embryo-immune mice) there exists a suppressor cell population which inhibits an anti -embryo cytotoxic response far more than an antiallograft response.

Inhibition of cell proliferation rather than of cell lysis as a measure of immune reactivity in embryo-antigen-challenged mice

“…-Retired breeder mice from Jackson Laboratories were inspected twice weekly for the appearance of spontaneous tumours. When such a tumour (mammary adenocarcinoma: Department of Histology/ Pathology, Princess Margaret Hospital) was -1.5 cm3 in volume the animals were killed by cervical dislocation, the tumour removed aseptically in phosphate-buffered saline (PBS) and an enzyme digest made of the solid mass as described earlier (Gorczynski, 1978;Russell et al, 1976). The yield was routinely of the order 5-9 x 107 viable cells.…”

“…When tumours were resected the operation was performed under ether anaesthesia. Tumour volume was measured as described elsewhere (Gorczynski, 1978;Attia et al, 1965).…”

“…Preparation of lymphoid cells, embryo fibroblasts, embryo cell extracts, irradiation, velocity sedimentation and cell culture techniques.-These have all been described in detail elsewhere (Gorczynski, 1978).…”

“…Microcytotoxicity and cytostasis assays.-The cytotoxicity assay has been described in detail elsewhere (Gorczynski, 1978 (Freund, 1962).…”

“…WE HAVE REPORTED several studies investigating the ability of embryo-immunized lymphocyte populations to show cytotoxicity to syngeneic embryonic fibroblast cells in vitro (Gorczynski, 1976a,b,c;1978) and have recently shown a correlation between this cytotoxicity and the ability of those cells to modify the growth characteristics of an s.c. tumour implant in vivo (Gorczynski & MacRae, unpublished). In contrast to these findings are those in which no tumour growth inhibition (or enhanced tumour growth) was observed using embryo-immune lymphoid cell populations (Pearson & Freeman, 1968;Ting, 1968;Basombrio & Prehn, 1972).…”