Malignant tumor cell lines produce interleukin-1-like factor.

Sixty-four malignant cell lines were examined for interleukin-1 (IL-1) activities in their conditioned medium using thymocyte and fibroblast proliferation assays. Sixteen cell lines showed high IL-1 activity. Comparison of these activities with human IL-1 showed similarity between some biological properties.

Monoclonal antibodies against human oral squamous cell carcinoma reacting with keratin proteins.

Two mouse monoclonal antibodies (MoAbs), B10 and 1H5, were generated by fusing mouse myeloma NS-1 cells with spleen cells from a BALB/c mouse immunized with Ueda-1 cells derived from human squamous cell carcinoma (SCC) of the floor of the mouth. Immunohistochemical analysis revealed that these MoAbs recognize the filamentous components of cytoplasm which were protein in nature. While the pattern of antigen distribution in various cell lines was not cell-type specific, reactivity of these antibodies with tissue sections was informative.

Mechanism of antitumor activity in mice for anti-epidermal growth factor receptor monoclonal antibodies with different isotypes.

In previous studies of monoclonal antibodies (mAbs) against the receptor for epidermal growth factor (EGF) both 528 IgG2a and 225 IgG1 were shown to inhibit growth of A431 cell xenografts in athymic mice. The antitumor activities of the two mAbs were similar and, although they differ in their isotypes, they share many properties. The two mAbs bind to EGF receptors with identical affinities, compete with EGF for binding to EGF receptors, down regulate the receptors identically, block EGF-induced activation of tyrosine protein kinase activity to a comparable degree, and block EGF-induced changes in the proliferation of cultured cells.

[Changes of peripheral lymphocyte subsets in patients with oral squamous carcinoma].

The distribution of peripheral lymphocyte subsets of 32 patients, who had undergone surgical removal of squamous carcinoma and have evaded recurrence was studied using OK series monoclonal antibodies. The T-lymphocyte subpopulation was reduced in patients who were tumor free for more than 3 years. The helper/inducer T-cell subpopulation was reduced in most of the patients studied, whereas little change was observed in the subpopulation of suppressor/cytotoxic T cells.