Recently, the alteration of peripheral T cells has become a focus of attention in research on Crohn's disease (CD). To examine the characteristics of peripheral T cells in CD patients, we analyzed the expression of a memory T cell marker (CD45RO(Bright)CD3+) and the cytokine production by peripheral helper and cytotoxic T cells in patients with CD. With the use of monensin to prevent the secret...

Pulmonary infections with Pneumocystis carinii are an important cause of morbidity and mortality in patients with AIDS. P. carinii infections are seen in patients with decreased numbers of helper T lymphocytes, suggesting that these cells are important in preventing infection. To test this hypothesis, we sought to establish experimental infection with P. carinii in mice selectively depleted of ...

CD4 + T lymphocytes provide contact-dependent stimuli to B cells that are critical for the generation of specific antibody responses in a process termed T helper function. The surface structures on activated CD4 + T cells that mediate this function are not fully known. We previously reported the isolation of a functionally unique subclone of the Jurkat leukemic T cell line (D1.1) that constitut...

A man from Chile developed an aggressive mature T cell leukemia associated with marked eosinophilia. The neoplastic lymphocytes were of T helper surface phenotype, and they expressed the p24 and p19 antigens of human T cell leukemia virus (HTLV). A cell line (ME) was established from the patient's peripheral blood cells that was initially composed of eosinophils and T and B lymphocytes. The B l...

CD4+ T lymphocytes provide contact-dependent stimuli to B cells that are critical for the generation of specific antibody responses in a process termed T helper function. The surface structures on activated CD4+ T cells that mediate this function are not fully known. We previously reported the isolation of a functionally unique subclone of the Jurkat leukemic T cell line (D1.1) that constitutiv...

Abnormalities of T lymphocytes in B cell chronic lymphocytic leukemia (B-CLL) have been extensively documented by several immunologic investigations. Following recent studies pointing to the favorable effect of TP-1, a partially purified extract of calf thymus, on the T cell-mediated immunity of several diseases, including Hodgkin's disease, we have used monoclonal antibodies and the enriched T...