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31.
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We have cloned a segment of the human gene encoding UDP-galactose translocator by genetic complementation of its defective mutant in mouse FM3A cells. Chromosome mapping using fluorescentin situ hybridization revealed that the cloned gene hybridized to the Xp11.23-11.23 region of the X chromosome. This region is shared by the locus of Wiskott-Aldrich syndrome, an X-linked recessive immunodeficiency disorder, characterized by defective sugar chains on cell surface components. Genetic and phenotypic similarities suggest a possible link between UDP-galactose translocator and the Wiskott-Aldrich syndrome (WAS).  相似文献   
33.
A 5' nuclease TaqMan PCR was developed for the quantitative detection of the periodontopathic bacteria Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. The relative numbers of bacteria were measured by the comparative threshold cycle method. This simplified method is a way of obtaining the relative quantities of these organisms from specimens and of monitoring the effect of therapy.  相似文献   
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35.
Using cDNA microarray technology, the expression of chemokine genes in the elicitation site of 2,4,6-trinitrochlorobenzene-induced contact hypersensitivity (CHS) was examined in mice. Of the 33 genes analyzed, levels of 11 gene expressions changed, and these can be assigned to four groups based on their kinetic patterns; (1) LARC/CCL20 whose mRNA level increased rapidly at 3 h post-challenge and then gradually decreased, (2) JE/CCL2, MARC/CCL7, MIP-1gamma/CCL9, monocyte chemoattractant protein (MCP)-5/CCL12, ELC/CCL19 and BRAK/CXCL14 whose mRNA levels increased with time and reached the maximum at 6-9 h post-challenge, (3) LIX/CXCL5, Mig/CXCL9 and IP-10/CXCL10 whose mRNA levels increased gradually at least up to 12 h post challenge, and (4) SLC/CCL21 whose mRNA level decreased gradually with time after challenge. The findings suggest that sequential expression of chemokine genes is essential for orientating non-specific skin response to hapten-specific CHS response through the recruitment of inflammatory cells such as neutrophils, monocytes/macrophages and T-cells from the circulation into the tissue site.  相似文献   
36.
Appearance of extrachromosomal circular DNAs with in vivo and in vitro cellular ageing was examined by using a new technique of mica-press-adsorption for electron microscopy. The size distribution and the copy number of circular DNA complexes varied, depending on the cellular age. Extrachromosomal circular DNA complexes of variable length of more than 0.5 microns or 1.5 kilobase (kb) appeared during in vivo ageing of rat lymphocytes and in vitro ageing of cultured human lung fibroblasts. A restricted size class of circular forms of less than 0.5 microns in contour length was amplified in human skin fibroblasts from aged normal or Werner's syndrome subjects. These circular DNA molecules are suggested to be products of DNA rearrangements or gene amplification occurring in the chromosome.  相似文献   
37.
A case of giant inflammatory polyposis associated with a localized inflammatory bowel disease of the descending colon in a 49-year-old man is presented. Lower abdominal distension rapidly appeared without any previous history of gastrointestinal disease. Two months later, he underwent a left hemicolectomy. Postoperative recovery was complete and he remains in good health more than 2 years later. The resected colon showed a giant and bizarre polyposis measuring up to 12 cm in length and 2 cm in height and covering the entire circumference of the colon. The polyposis consisted of narrow worm- or noodle-like polyps that bridged over the irregularly shaped ulcers, which sometimes extended into muscularis propria. Although longitudinal ulcers or scars, stricture, and a cobble-stone appearance were not observed, transmural inflammation and deep fissures were found in the interpolypoid area. From these findings, this case seems to be more similar to Crohn's disease than other inflammatory bowel diseases.  相似文献   
38.
Medullasin levels in granulocytes of patients with neurological diseases and healthy volunteers were determined by the enzyme immunoassay using mouse monoclonal antibodies against human medullasin and o-phenylenediamine-H2O2 as the detection system of the enzyme activity. One hundred twenty-one out of 159 patients with multiple sclerosis (76.1%) showed positive results (above means of normals + 2SD) in this test, while only 16.9% (24/142) of patients with non-inflammatory neurological diseases had positive results. This enzyme immunoassay method for medullasin is considered to be an useful paraclinical test for the diagnosis of multiple sclerosis.  相似文献   
39.
Involvement of the Harderian gland (HG) in the production of lacrimal immunoglobulin (especially IgA) was investigated. The lacrimal concentration of each immunoglobulin class was not affected by surgical bursectomy but was reduced by cyclophosphamide (CY) and testosterone (TP) treatments. Surgical removal of the Harderian gland caused a remarkable reduction of both the lacrimal concentration of each immunoglobulin class and the specific antibody titre, and and IgA was almost undetectable. The lacrimal concentration of each immunoglobulin class, as well as the specific antibody titre, was not affected by surgical removal of the Lacrimal gland (LG). The route of antigen administration produced no difference in the class of lacrimal immunoglobulin produced. The results indicate that the production of immunoglobulin in chicken tears may be dependent on the HG and that lacrimal immunoglobulin may be synthesized and secreted locally in the HG. Lymphocytes of the HG are of bursa of Fabricius origin and are seeded into the HG prior to hatching and its lymphocytes do not appear to be involved in systemic immunity.  相似文献   
40.
Physical interaction of T cells and dendritic cells (DCs) is essential for T cell proliferation and differentiation, but it has been unclear how this interaction is regulated physiologically. Here we show that DCs produce thromboxane A2 (TXA2), whereas naive T cells express the thromboxane receptor (TP). In vitro, a TP agonist enhances random cell movement (chemokinesis) of naive but not memory T cells, impairs DC-T cell adhesion, and inhibits DC-dependent proliferation of T cells. In vivo, immune responses to foreign antigens are enhanced in TP-deficient mice, which also develop marked lymphadenopathy with age. Similar immune responses were seen in wild-type mice treated with a TP antagonist during the sensitization period. Thus, TXA2-TP signaling modulates acquired immunity by negatively regulating DC-T cell interactions.  相似文献   
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