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The fat soluble vitamin D3 metabolite 1,25-dihydroxyvitamin D3 [1,25(OH)

Objective. To determine the value of measurement of serum soluble tumor necrosis factor receptor (sTNFR), compared with established parameters such as anti-double-stranded DNA, in monitoring systemic lupus erythematosus (SLE) disease activity, and to determine whether serum sTNFR are bioactive and can effectively inhibit TNF bioactivity .Methods. Fifty-three consecutive ambulatory or hospitalized SLE patients and 140 consecutive healthy subjects were enrolled in a prospective cohort study. Serum levels of sTNFR were measured by a unique 2-sided capture enzyme-linked immunosorbent assay

Penicillin-allergic patients were more likely to receive broader spectrum antibiotics compared to the non-allergic ones. Since many of the patients who are labelled as being 'allergic to penicillin' are, in fact, not allergic to it, inaccurate reporting of penicillin allergies may have costly economic and epidemiologic repercussions in addition to more toxic effects which can occur when choosing alternative drugs in case of penicillin allergy.

In view of a high frequency of liver involvement in patients with essential mixed cryoglubulinemia, we looked for evidence for hepatitis B virus infection in 25 serum specimens and 19 cryoprecipitates obtained from 30 patients. Three of the 25 serum specimens contained Hbs Ag, and 12 had antibody. The frequency of positive results was increased to six and 11 of 19 respectively when cryoprecipitates were examined, and 14 of 19 (74 per cent) of the cryoprecipitates were positive for either HBs Ag or its antibody. Electron microscopy of four cryoprecipitates showed structures resembling the 20-nm and 27-nm spheres, tubules, as well as the Dane particles characteristic of hepatitis B virus infection. Since such infection appears to be involved in the pathogenesis of the syndrome, the term "essential mixed cryoglobulinemia" should be replaced by "mixed cryoglobulinemia secondary to hepatitis B virus" or perhaps to other viral infections.

The mechanism by which immature B cells are sequestered from encountering foreign antigens present in lymph nodes or sites of inflammation, before their final maturation in the spleen, has not been elucidated. We show here that immature B cells fail to home to the lymph nodes. These cells can actively exclude themselves from antigen-enriched sites by downregulating their integrin-mediated adhesion to the extracellular matrix protein, fibronectin. This inhibition is mediated by interferon γ secretion. Perturbation of interferon γ activity in vivo leads to the homing of immature B cells to the lymph nodes. This is the first example of autocrine regulation of immune cell migration to sites of foreign antigen presentation.

Activation of naive T and B cells occurs only within the context of organized lymphoid tissue. Thus, the continuous recirculation of mature lymphocytes is crucial for the development of primary immune response to foreign Ags. We have previously shown that low levels of IFN-γ inhibit homing of B cells to the secondary lymphoid organs. In this study, we demonstrate that similarly low doses of IFN-γ down-regulate integrin-mediated adhesion and migration of naive T and Th2 cells, and have a profound effect on the in vivo homing of naive T cells to the lymph nodes. Moreover, we show that these low doses of IFN-γ have anti-inflammatory effects in an in vivo asthma model. Thus, in contrast to the proinflammatory effects of IFN-γ at relatively high concentrations, low dose IFN-γ appears to exert global suppressory effects on T cell trafficking and may have clinical application as an anti-inflammatory agent.

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