Characterization of mice carrying multiple mutant genes which cause the different immunological defects.

多突变株，KSN-bg, KSN-xid, KSN-bg；xid是从裸菌株KSN中培育出来的。各品系小鼠均具有良好的繁殖性能，可用于小型实验。这些菌株包括微卫星标记在内的遗传图谱在检测位点上是相同的，表明这些菌株是同源的。携带米色基因、KSN-bg、KSN-bg小鼠nk细胞活性的研究虽然脾脏细胞的荧光活化细胞分析显示，在携带米色基因的小鼠中，用asialo-GM1抗体标记的NK细胞没有减少，但xid显著降低。这表明米色突变导致NK细胞活性降低是由于NK细胞功能受损所致。细胞分析还表明，xid突变导致脾脏B细胞数量减少，血清中IgG和IgM含量下降。然而，比较7种人类肿瘤细胞系在KSN、KSN-bg和KSN-xid小鼠中的可移植性，发现双突变小鼠没有优势。人类肿瘤在裸/bg/xid小鼠体内的可移植性目前正在研究中。这两种双突变小鼠没有提供人类双丝虫病的模型。将c -b -17 SCID与KSN-bg小鼠杂交，培育出米色突变SCID小鼠。将米色突变引入SCID小鼠后，NK细胞活性明显降低，大鼠骨髓移植实验表明，SCID-bg小鼠比SCID小鼠更容易吸收，从而导致SCID-bg小鼠更严重的移植物抗宿主反应。为了研究nk细胞活性对肿瘤发生的监测作用，比较了日剂量为160和320 J/m^2的uvb照射KSN和KSN-bg小鼠的肿瘤诱导作用。在160 J/m^2/d剂量下，KSN-bg小鼠皮肤肿瘤诱导率明显高于KSN小鼠，而在320 J/m^2/d剂量下，KSN小鼠皮肤肿瘤诱导率明显高于KSN小鼠。结果表明，nk细胞活性在紫外线致癌作用中的作用，如果有的话，是非常边缘的，仅在极低剂量的uvb照射后，较少

Multiple mutants strains, KSN-bg, KSN-xid, KSN-bg ; xid were bred from a nude strain, KSN.Each strain of mice has good reproduction performance and could be supplied for a small size experiment. Genetic profiles of these strains including microsatellite markers were identical so for examined loci, indicating these strains are congenic each other.. NK-cell activity of mice carrying beige gene, KSN-bg and KSN-bg ; xid was significantly reduced, although florescence-activated cell analysis of spleen cells indicated NK cells labeled with asialo-GM1 antibody were not decreased in mice with beige gene. This indicates that the reduced NK cell activity by beige mutation is due to the functional impairment of NK cells. The cell analysis also indicates that xid mutation induces the decrease in number of B cells in spleen and the amounts of IgG and IgM in serum. However, the comparison of the transplalntability of 7 human tumor cell lines in KSN,KSN-bg and KSN-xid mice, indicated no advantages in … More the double-mutant mice. The transplantability of human tumors in nude/bg/xid mice is now under investigation. These two kinds of double-mutant mice did not provide a model for human dirofilariasis. The SCID mice with beige mutation were also bred from the cross between C.B-17 SCID and KSN-bg mice. The introduction of beige mutation into SCID mice resulted in the significant reduction of NK cell activity and the transplantation of rat bone marrow experiments showed that SCID-bg mice take more easily than SCID mice, which result more severe Graft-versus-host reaction in the SCID-bg mice. In order to examine the surveillance effect of NK-cell activity in carcinogenesis, the tumor induction after UVB-irradiation were compared between KSN and KSN-bg mice at the daily doses of 160 and 320 J/m^2. At 160 J/m^2/day, significantly higher induction of skin tumor in KSN-bg mice than in KSN mice was observed, but at higher dose of 320 J/m^2/day higher induction was fouund in KSN mice. The results suggested that the role of NK-cell activity in UV-carcinogenesis, if any, is very marginal and after only very low dose of UVB-irradiation, Less