Phorbol ester-sensitive EL4 murine thymoma cells respond to phorbol 12-myristate 13-acetate with activation of ERK mitogen-activated protein kinases, synthesis of interleukin-2, and death, whereas phorbol ester-resistant variants of this cell line do not exhibit these responses. Additional aspects of the resistant phenotype were examined, using a newly-established resistant cell line. Phorbol e...

Several lines of evidence are presented to suggest that histocompatibility antigens can be physically associated on the cell surface with viral antigens and possibly other foreign antigens. The lysis of the murine tumor cells EL4 and P388 by syngeneic cytotoxic lymphocytes was inhibited by antisera directed against the H-2 antigens on the tumor cells, consistent with the hypothesis that H-2 ant...

Although nicotine is a risk factor for carcinogenesis and atherosclerosis, epidemiological data indicate that nicotine has therapeutic benefits in treating Alzheimer's disease. Our previous studies also showed that nicotine-treated dendritic cells have potential antitumor effects. Hence, the precise effects of nicotine on the biological characterizations of cells are controversial. The aim of th...

Many cervical cancers express the E7 protein of human papillomavirus 16 as a tumor-specific Ag (TSA). To establish the role of E7-specific T cell help in CD8+ CTL-mediated tumor regression, C57BL/6J mice were immunized with E7 protein or with a peptide (GF001) comprising a minimal CTL epitope of E7, together with different adjuvants. Immunized mice were challenged with an E7-expressing tumor ce...

The yeast GCN4 3* element represents a class of polyadenylation sites which function unidirectionally and efficiently in test systems in vivo as well as in vitro. A complex signal element is required for polyadenylation activity with a minimal size of 116 nucleotides for the functional element. We subdivided this element into five regions (EL1 to EL5) of 16 to 26 nucleotides each. Each region w...

Complement inhibitors expressed on tumor cells provide an evasion mechanism against mAb therapy and may modulate the development of an acquired antitumor immune response. Here we investigate a strategy to amplify mAb-targeted complement activation on a tumor cell, independent of a requirement to target and block complement inhibitor expression or function, which is difficult to achieve in vivo....

Tpl-2 expression is induced within 30-60 min after ConA stimulation of rat splenocytes, suggesting that it may contribute to the induction of IL-2 during T cell activation. Herein we show that wild-type and carboxyl-terminally truncated (activated) Tpl-2 activate the nuclear factor of activated T cells (NFAT) and induce interleukin 2 (IL-2) expression in EL4 cells. In Jurkat cells the truncated...

was produced in a coisogenic B10.D2 (H^) strain of mice by intra|)oritoncal injection of the tissue preparations together with adjuvant. -/-Globulins were precipitated by ammonium sulfate and subfractions separated on Sephadex G-200. These were examined by microelectrophoresis for effects on surface charges of EL4 lymphoma cells and for hemolytic potency in tests with histoincompatible erythroc...

Antigen-activated T lymphocytes produce within 24 h of stimulation a factor that is indistinguishable biochemically and functionally from the B cell co-stimulating growth factor, BCGF-I, originally identified in induced EL4 supernatants: Supernatants from antigen-stimulated T cell lines are not directly mitogenic for resting B cells, but synergize in an H-2-unrestricted manner with anti-Ig acti...

immunity (Calmette-Guérin bacilli and corynebacteria) (1 1) and even by transfer of lymphoid cells from appropriately preimmunized animals (6). Animals. All mice were bred in our own colony and rabbits for immunization were bought from accredited dealers. The carcinogen-induced lymphoma EL4 is specific for C57BL/6 mice (8) and was maintained by i.p. passage in that strain. Antisera. Groups of ...