Expression of mouse embryonic epitope TEC-2 on human carcinoma-derived cell lines and characterization of its glycoprotein carriers.

Monoclonal antibody TEC-02, raised against mouse embryonal carcinoma cells, has been shown to react with murine preimplantation embryos and with a very limited number of adult mouse tissues. The target epitope, TEC-2, is a carbohydrate carried in mouse embryonal carcinoma cells by large glycoprotein-bound glycan. We report here the expression of TEC-2 epitope on human carcinoma-derived cell lines, HeLa and HS, and the properties of its carbohydrate carriers.

Immunotherapy of murine sarcomas with interleukin 2. II. Activation of killer cells by human recombinant IL-2.

Highly purified human recombinant interleukin 2 induced cytotoxicity in mouse spleen cells against mouse sarcoma cells when added during the 51Cr microcytotoxicity assay. It elicited similar levels of killer cell activation as did human lymphoid (Jurkat leukaemia-derived) or mouse lymphoid (EL-4 leukaemia-derived) IL-2 preparations. The susceptibility of six MC-induced mouse sarcomas to the cytolytic effect of lymphokine-activated killer cells was compared.

Immunotherapy of murine sarcomas with interleukin 2. I. Local administration of human recombinant IL-2 preparations.

The immunotherapeutic effect of human recombinant interleukin 2 was examined with a panel of MC-induced murine sarcomas carrying individual tumour-specific transplantation antigens. Repeated peritumoral injections of RIL-2 inhibited growth of five (MC11, MC13, MC14, MC15, MC16) out of six sarcomas in syngeneic mice. The sixth murine sarcoma (MC12) was resistant to the tumour-inhibitory effect of human recombinant IL-2 as well as to the tumour-inhibitory effect of murine and rat lymphoid IL-2 preparations.

Activation of killer cells from blood of urinary bladder carcinoma patients by short-term treatment with recombinant interleukin 2.

Highly purified recombinant human interleukin 2 induced cytotoxicity of lymphocytes from urinary bladder carcinoma patients and from control healthy donors when added during an 18-h 51Cr microcytotoxicity assay against bladder carcinoma (T24) target cells. Similar levels of killer cell activation were detected in mononuclear cell preparations from bladder carcinoma patients and control healthy donors; hence, no defect in the responsiveness of bladder carcinoma patients' lymphocytes to interleukin 2 could be observed. The effect of the recombinant interleukin 2 was dose-dependent.

Tumour inhibitory effects of TCGF/IL-2/-containing preparations.

Supernatants from ConA-stimulated rat spleen cell cultures and from cultures of PMA-stimulated murine lymphoma subline EL-4TF were found to contain TCGF and to inhibit growth of a transplantable, MC-induced sarcoma MC11 in syngeneic mice. Tumour-inhibitory effects of the supernatants were dependent on local and repeated administration. Prior to use of the supernatants obtained from PMA-stimulated EL-4TF cell cultures, the dialysable PMA had to be removed; contamination with PMA was found to abolish the tumour-inhibitory effect of the supernatants and to produce enhancement of tumour growth.