Eicosapentaenoic acid inhibits antigen-presenting cell function of murine splenocytes.

Recently, many investigators have studied the effects of eicosapentaenoic acid (EPA)-rich fish oil on immune function and immune disease. However, effects of dietary supplementation of fish oil or EPA on the immune system are still unclear. In the present study, the effects of EPA on antigen presentation were investigated. We have used antigen-specific helper T-cell clones that proliferate in the presence of antigen [keyhole limpet haemocyanin (KLH)] and spleen cells as antigen-presenting cells (APC). Mice were divided into two groups and fed an experimental diet or a control diet for 4 weeks ad libitum. In mice fed the experimental diet, the arachidonic acid (AA) content of spleen cells was decreased and that of EPA and docosapentaenoic acid was increased markedly compared to those of the control diet. Dietary enrichment with EPA inhibited the ability of accessory cells to present antigen to murine helper T-cell clones. This effect was observed for two distinct helper T-cell clones, Th1 and Th2. We also examined the effects of EPA-TG emulsion on APC function. The direct addition of EPA-TG emulsion to a T-cell proliferation assay system suppressed APC function. The inhibition was proportional to the concentration of EPA-TG emulsion. Pretreatment of splenocytes with EPA-TG emulsion resulted in inhibition of APC function. Inhibition of antigen presentation by dietary supplementation with EPA might depress immune reactivity.     

Regional differences of PCB and PCQ concentrations in the blood and subcutaneous fat tissue of residents of Nagasaki

In this study, we analyzed PCB and PCQ concentrations in the subcutaneous fat tissue of residents of Nagasaki Prefecture, and compared these levels between the blood and subcutaneous fat tissue of people living in various parts of the prefecture. Seventy-one inhabitants were examined. In the blood, PCB concentrations in Tamanoura and Fukue were significantly higher than those in Nagasaki City. The CB% ratio in Tamanoura was significantly higher than that in Nagasaki and Isahaya. PCQ concentrations were below detection level except in one case. PCB concentrations in fishery areas showed higher levels than urban or agricultural areas. PCB concentration in the subcutaneous fat tissue was 100 times higher than that in the blood. PCQs could be detected in almost all of the subcutaneous tissues, but there was no regional difference in the PCQ concentration.     

Thymocyte activating factors from SV40-transformed human embryo fibroblasts

A novel factor was found in the medium conditioned by SV40-transformed human embryo fibroblasts, which stimulate concanavalin A-induced thymocyte DNA synthetic response. This activity was estimated to be 10-15 kD and divided into two activities by ion exchange chromatography. One of them is a protein molecule and the other is a glycoprotein. In addition, these activities are not derived from the growth factors reported previously such as interleukin 2 (Morgan, R., Ruscetti, F. and Gallo, R. C. (1976) Science 193, 1007-1008) and transforming growth factor (De Larco, J. E. and Todaro, G. J. (1978) Proc. Natl. Acad. Sci. U.S.A. 75, 4001-4005).     

Phasically firing neurons in the supraoptic nucleus of the rat hypothalamus: immunocytochemical and electrophysiological studies

Relations between firing patterns and peptides in supraoptic neurons of rat hypothalamic slice preparations were studied by electrophysiology, intracellular fluorescent dye-marking and immunocytochemistry. Seven out of 10 magnocellular neurons which showed phasically firing patterns were identified by injections of Lucifer Yellow-CH (LY); these were also stained with an anti-vasopressin serum. This report presents direct evidence that most of the phasically firing neurosecretory neurons in the supraoptic nucleus contain vasopressin. This study demonstrates the feasibility of combining immunocytochemical and electrophysiological techniques to study the peptides contents of single mammalian neurons.     

HLA antigens in Behçet''s disease with refractory ocular attacks

HLA class I, II, and III antigens were studied in Japanese patients with Beh?et's disease with refractory ocular attacks. In addition to the increased frequency of B51, DQw3, especially TA10-negative DQw3, was increased and DQw1 was decreased significantly in this subgroup of Beh?et's disease. As for complement markers, C4A Q0 was increased. A rare variant of BF S07 was first observed in Japanese. Although the mechanism for the DQw3 association is obscure, a possible hypothesis is that an immune-response or immune-suppression gene linked to the DQ antigens modulates the disease severity and the efficacy of treatments.     

Retrospective survey of urea cycle disorders: Part 1. Clinical and laboratory observations of thirty-two Japanese male patients with ornithine transcarbamylase deficiency

In a retrospective survey done from 1978-1988 in Japan, 32 male patients with ornithine transcarbamylase (OTC) deficiency were identified. We classified a neonatal and 2 late-onset groups, depending on clinical manifestations and the age at onset; group 1 (0-28 days; N = 10), group 2 (29 days-5 years; N = 13), and group 3 (greater than 5 years; N = 9). Compared to findings in the group 2 patients, there was a higher rate of mortality and a higher incidence of mental retardation in association with a great decrease in enzyme activity in group 1. In group 3, the mortality rate and enzyme activities were similar to those in group 1. However, patients in this group were asymptomatic prior to the first episode. Enzyme activities were measured mostly in autopsy samples. The serum citrulline levels (enzyme product) were highest in this group. Thus, the mutant enzymes were apparently labile with greater activities in vivo than in vitro. Treatments, including a protein-restricted diet, arginine supplementation, and sodium benzoate administration, resulted in a favorable prognosis for survivors with partial enzyme deficiency. We wish to emphasize that the incidence of late onset of this disease is higher than heretofore considered.     

Eosinophilic granuloma showing rapid regression. Report of a mandibular case with application of a modified PNA staining method for demonstration of Langerhans-type histiocytes.

A mandibular eosinophilic granuloma in a 16-year-old male is reported. This case showed rapid regression, which was clearly demonstrated by histopathological examinations of both preoperative biopsy and surgical materials. Transformation from an eosinophilic granuloma to a xanthomatous granuloma with multinucleated giant cells was observed after only 26 days. Special staining of paraffin sections with peanut agglutinin (PNA) and use of electron microscopy showed that the main component of the lesion in the biopsy material was Langerhans-type histiocytes. These cells had disappeared from the lesion by the time of the operation. At the same time, the number of infiltrating eosinophils was also markedly reduced. It seems appropriate to consider that the rapid regression of this disease was correlated with the rapid reduction in the number of Langerhans-type histiocytes appearing in the granulomatous foci, as well as the number of infiltrating eosinophils.     

Fine structure of hepatic sinusoids and their development in human embryos and fetuses

The fine structure of the hepatic sinusoids of 81 human embryos and fetuses and their development from 5 to 12 weeks gestation were studied. At 5 weeks gestation, sinusoid-like structures and Kupffer-like cells were observed between liver cell cords. Between 6 and 8 weeks gestation the sinusoids were completely developed. Definite Kupffer cells appear at this developmental stage, when the bone marrow has not yet formed. Floating macrophages form cell aggregates in the sinusoids which contact endothelial cells and settle as Kupffer cells. Erythroblastophagia is observed in Kupffer cells and macrophages. The endothelial linings are closed, with the attenuated cell processes and intercellular junctions between the adjoining endothelial cells. No transition was observed between Kupffer cells and endothelial cells. The findings suggest that Kupffer cells in the human embryo are extrahepatic in origin and that they reach the sinusoids via the circulatory system. Ito cells, which store fat, originate from mesenchymal cells in the septum transversum.