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111.
The human non-classical MHC class I molecule HLA-E is a ligand for both an inhibitory NK cell receptor (CD94/NKG2A) and an activating receptor (CD94/NKG2C). To identify HLA-E surface recognized by both receptors, especially to determine if both receptors recognize the same epitope, we made a series of individually Ala-substituted HLA-E proteins and analyzed their binding to CD94/NKG2A orCD94/NKG2C. Eight HLA-E mutations that significantly impaired HLA-E binding to CD94/NKG2A are all found in the top of alpha1/alpha2 domain of HLA-E. These results suggest that CD94/NKG2A binds a HLA-E surface equivalent to a NKG2D binding site on MICA. Of the eight mutations that impaired HLA-E binding to CD94/NKG2A, six significantly impaired HLA-E binding to CD94/NKG2C suggesting that CD94/NKG2C also binds a similar surface of HLA-E. Unexpectedly, the two HLA-E mutations (D69A and H155A) selectively abrogated HLA-E binding to CD94/NKG2A, not largely affected CD94/NKG2C. These results indicate that a mostly shared, but partly distinct set of HLA-E residues is discriminated by the two receptors. 相似文献
112.
113.
Hiroyuki Usuda Iwao Emura Makoto Naito Tatsuhiko Hirono 《Pathology international》1995,45(12):940-946
Three cases of peripheral small cell lung carcinoma (SCLC) with central fibrosis are presented. Central fibrosis is usually present in adenocarcinomas. Cases 1 and 2 are combined SCLCs with components of papillary adenocar-cinoma, and case 3 is a mixed SCLC with a large cell component. Small cell Components showed intermediate cell type in ail cases. In cases 1 and 2, there was a gradual transition between small cell carcinoma and papillary ade-nocarcinoma. Small cell components showed Grimelius argyrophilia, but other neuroendocrine markers such as neuronspecific enorase, chromogranin A, Leu-7 and syn-aptophysln were negative. The chest X-ray examination of case 1 demonstrated rapid enlargement of a tumor shadow, which was present two years before, for a recent year. Central fibrosis, coexistence of small cell carcinoma and papillary adenocarcinoma, and a change of growth rate in the chest x-ray may suggest that some SCLC derive from papillary adenocarcinomas. 相似文献
114.
Ahmadiyeh N Churchill GA Solberg LC Baum AE Shimomura K Takahashi JS Redei EE 《Behavior genetics》2005,35(2):189-198
A genome-wide scan was carried out on a segregating F2 population of rats derived from reciprocal intercrosses between two inbred strains of rats, Fisher 344 (F344) and Wistar Kyoto (WKY) that differ significantly in their behavioral coping responses to stress measured by the defensive burying (DB) test. The DB test measures differences in coping strategies by assaying an animals behavioral response to an immediate threat. We have previously identified three X-linked loci contributing to the phenotypic variance in behavioral coping. Here we report on six significant autosomal quantitative trait loci (QTL) related to different behaviors in the DB test:one for the number of shocks received, three for number of prod approaches, one for latency to bury, and one pleiotropic locus affecting both approach and latency. These QTL contributing to different aspects of coping behaviors show that the effect of genotype on phenotype is highly dependent on lineage. The WKY lineage was particularly influential, with five out of the six QTL affecting coping behavior only in rats of the WKY lineage, and one locus affecting only those in the F344 lineage. Thus, epigenetic factors, primarily of WKY origin, may significantly modulate the genetic contribution to variance in behavioral responses to stress in the DB test. 相似文献
115.
116.
Katagiri YU Ohmi K Tang W Takenouchi H Taguchi T Kiyokawa N Fujimoto J 《Laboratory investigation; a journal of technical methods and pathology》2002,82(12):1735-1745
SUMMARY: Raft microdomains are glycolipid-enriched microdomain scaffolding molecules involved in signal transduction. The binding of Shiga toxin to globotriaosyl ceramide in raft microdomains of the human renal tubular cell line ACHN causes temporal activation of Src-kinase Yes. To study the downstream signaling mechanism proceeding to the activation of Yes, we raised monoclonal antibodies (MAbs) against raft microdomains. The MAbs were screened on the basis of, first, binding to raft microdomains with dot-blot immunostaining, second, intracellular localization of the epitope by flowcytometry after permeabilization, and third, translocation of the antigen molecules after Stx treatment by immunohistochemical staining. Raft.1 MAb bound to the molecules that accumulated to the particular region near the nucleus after Stx treatment. Two-dimensional Western blotting and matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis revealed that the antigen molecule is GTP binding protein beta subunits 1 and 2 (Gbeta1 and 2). That Raft.1 recognized Gbeta1 and 2 was further confirmed by the reactivity to recombinant Gbeta1 and 2 proteins. To our knowledge, this is the first report of production of a MAb recognizing Gbeta1 and 2. Because Gbeta1 and 2 are highly conserved all through organisms and are deeply involved in signal transduction, Raft.1 is expected to be utilized frequently in research. 相似文献
117.
118.
Predominance of canine parvovirus (CPV) in unvaccinated cat populations and emergence of new antigenic types of CPVs in cats 总被引:13,自引:0,他引:13
Serological, sequence, and in vitro host range analyses of feline parvovirus (FPV) isolates in Vietnam and Taiwan revealed that more than 80% of the isolates were of the canine parvovirus (CPV) type, rather than feline panleukopenia virus (FPLV). Although parvovirus isolates from three Vietnamese leopard cats were genetically related to CPV type 2a or 2b, they had a natural mutation of VP2 residue 300 Gly to an Asp, resulting in remarkable changes in their antigenic properties. These results indicated the possibility that CPV-2a/2b-type viruses can spread in cats more efficiently than conventional FPLV under natural conditions and that CPV-2a/2b viruses are further evolving in cats. 相似文献
119.
Kenichi Wakasa Tomoko Haba Masaomi Sasaki Masami Sakurai Takashl Ikebe Taichi Shuto Kazuhiro Hirohashi Hiroaki Kinoshita 《Pathology international》1998,48(1):29-32
In the cirrhotic and precirrhotic liver, there may be small foci with increased cellularity and amphophilic cytoplasm. These are microscopic lesions that do not form macroscopically detectable nodules, which differ from the macroscopically apparent nodules of dysplastic nodules. In the present study, we assessed the proliferating activity of 12 hyperplastic foci in 11 patients with cirrhosis or chronic hepatitis, by staining for agyrophilic nucleolar organizing regions (AgNOR). The mean AgNOR count per nucleus in the hyperplastic foci ranged from 0.96 to 1.36 (mean, 1.13; SD 0.12), and from 0.81 to 1.06 (mean, 0.94; SD 0.08) in the controls. The AgNOR count In the hyperplastic foci was significantly higher than that In the controls (P> 30.01). Small hyperplastic foci show Increased proliferative activity. Further study on these foci is required to clarify their relation to hepatocarcinogenesis. 相似文献
120.
In an autopsy case of a 35-year-old Japanese hemophiliac with acquired immune deficiency syndrome (AIDS), many multinucleated giant cells (MGCs) were observed throughout the central nervous system. Immunohistochemically, MGCs possessed surface and cytoplasmic macrophage antigens expressed in the late stage of differentiation indicating them to be macrophages in the terminal stage of differentiation. Fine nuclear extensions connecting one nucleus (or lobe) to another were often observed in the MGCs. This feature was interpreted as multilobulation and considered to be a morphological characteristic of MGCs in AIDS encephalopathy. Similarity between MGCs in AIDS encephalopathy and highly lobulated lymphocytes in adult T cell leukemia is discussed. 相似文献