Objectives-A population based casecontrol study was conducted in a highly agricultural area in the north east CLLs and low grade NHLs. This finding could be related to the use of chemicals in agriculture or to exposure to animal transmitted diseases or specific chemicals used in animal breeding. (Occup Environ Med 1995;52:374-379)

Phytohemagglutinin (PHA)-induced human T cell clones (TCC) derived from conjunctival flogistic tissues of 3 patients with vernal conjunctivitis produced unusually high amounts of interleukin-4 (IL-4) and no, or limited amounts of, gamma-interferon (IFN-γ). Allergen (Dermatophagoides pteronyssinus or Lolium perenne group I)-specific TCC derived from peripheral blood of two atopic donors produced significantly higher amounts of IL-4 and significantly lower amounts of IFN-γ than TCC specific for bacterial antigens (tetanus toxoid and PPD) contemporarily established from the same donors. These data provide evidence for a compartimentalization of Th2-like helper T cells in target organs and in the allergen-specific T cell repertoire of allergic patients. Non-B, non-Tbone marrow cells could produce IL-4, but not IL-2 or IFN-γ, in response to cross-linkage of Fcε type I receptors. These cells may further contribute to the maintenance and amplification of allergic inflammation.

No abstract

T Lymphocytes from thyroid infiltrates and peripheral blood (PB) of 3 patients with Hashimoto's thyroiditis (HT) were cloned using a microculture system previously shown to allow the clonal expansion of virtually all PB T lymphocytes from normal individuals. The phenotypic and functional features of a total number of 153 clones from thyroid infiltrates and 206 clones from PB were examined and compared with those of 272 clones derived from normal PB and spleens. The majority of clones derived from thyroid infiltrates of patients with HT had the cytotoxic/suppressor (T8+) phenotype, whereas the majority of clones from PB expressed the helper/inducer (T4+) phenotype. In addition, a consistent proportion (25%) of clones derived from PB of one patient had a phenotype (T3+T4-T8-) that was only occasionally found on clones obtained from PB or spleens of normal subjects. Most clones derived from both PB and thyroid infiltrates of the patients with HT had cytolytic activity, assessed by a lectin-dependent cytolytic assay against the murine P815 tumor cell line. The high frequency of cytotoxic T cells in thyroid infiltrates was related to the increased proportion of T8+ cells, whereas enhanced percentages of cytotoxic cell precursors with T4+ and T3+T4-T8- phenotypes primarily accounted for the high frequency of cytolytic T cells in the PB of the same patients. Many cytolytic T cell clones derived from thyroid infiltrates also had natural killer activity against human K562 and MOLT-4 target cells. These data provide the first functional analysis of T lymphocytes infiltrating the thyroid gland in patients with HT and suggest that the high proportions of cytolytic T cell precursors found in both thyroid infiltrates and PB of these patients may be of importance in determining the tissue damage in thyroid autoimmune disease.

The IgE helper function of human T cell clones or their phytohemagglutinin-induced supernatants was positively correlated with their ability to produce or their content in interleukin 4 (IL-4), whereas it was inversely correlated with production of or content in gamma interferon. The addition to B cell cultures of anti-IL-4 antibody abolished not only the IgE synthesis induced by recombinant human IL-4, but also that induced by IL-4-producing T cell clones or their phytohemagglutinin-induced supernatants. A clonal analysis in non-atopic donors and patients with common atopy showed that atopies possess in their peripheral blood significantly higher numbers of T cells able to secrete IL-4 and to provide helper function for IgE.