Mesenchymal differentiation and organ distribution of established human stromal cell lines in NOD/SCID mice.

Two human stromal cell lines were established previously from bone marrow-derived primary long-term cultures by immortalization using the SV40 large T antigen and cellular cloning. After irradiation, the fibroblast-like cell lines L87/4 and L88/5 support hematopoietic differentiation of allogeneic cord blood cells in vitro. The stromal cells do not express CD34 and CD50, but some adhesion molecules and integrins, such as CD44, CD54 and CD58. Their expression profiles on RNA and protein levels are suggestive of their osteogenic potency. The quality and quantity of osteocalcin and osteopontin protein expression depended on the culture conditions. Expression of the osteogenic markers increased over time in culture, especially in cells growing in clusters. The stromal cells also expressed collagens I and V, but did not show any expression of collagens II and III. The potentially osteoblastic stromal cells were transplanted into NOD/ SCID recipient mice by intravenous injection and were found in various mesenchymal organs up to 10 weeks after transplantation. Osteocalcin-positive human stromal cells could be detected in the bone marrow, thymus, liver, brain and gut of the recipient animals. In summary, there is evidence that human bone-marrow-derived stromal cells have to be considered mesenchymal progenitors, persistently expressing osteogenic markers in vitro and in vivo.     

A possible autocrine role for interleukin-6 in two lymphoma cell lines

Interleukin-6 (IL-6) is a growth factor with diverse biologic activity. Originally described as a T-cell product that enhances immunoglobulin (Ig) secretion in antigen-stimulated B cells, it also affects the growth of T cells, plasmacytomas, hybridomas, and hematopoietic stem cells. We report the expression and secretion of IL-6 by two lymphoma cell lines, OCI-LY3 and OCI-LY12. Addition of recombinant IL-6 stimulated their growth, whereas addition of polyclonal anti- recombinant IL-6 (anti-rIL-6) had a marked inhibitory effect on proliferation. These results suggest an autocrine role for IL-6 in the growth of these lymphoma cells in culture.     

T细胞接种对环磷酰胺处理NOD小鼠糖尿病的影响

目的 探讨T细胞接种（TCV）对Ⅰ型糖尿病的预防作用。方法 将6周龄未发病的雌性NOD鼠用4周龄未发病、18周龄新近发病和32周龄发病时间长的NOD鼠脾细胞制得的T细胞疫苗接种,检测TCV对环磷酰胺处理的NOD鼠糖尿病发病率和胰岛炎程度的影响,以及接种后宿主淋巴细胞亚群的变化情况。结论 TCV可以降低糖尿病发病率、减轻胰岛单个核细胞的浸润程度,诱导宿主脾脏CD8^ T细胞百分比升高、CD4^＋／CD8^ 比值和IL－2R^ 细胞下降,胸腺CD4^- CD8^-单阳性细胞百分比升高。结论 TCV可降低宿主对自身免疫的反应性,这种作用可能与宿主脾脏、胸腺淋巴细胞亚群的变化和对糖尿病的预防效应有关。     

Targeting of IL-2 receptor with a caspase fusion protein disrupts autoimmunity in prediabetic and diabetic NOD mice

Aims/hypothesis  

Interruption of IL-2 signalling is an attractive therapeutic target in autoimmune disorders. In this study we evaluated the effect of a fusion protein composed of IL-2 and caspase-3 (IL2–cas) on NOD mice, as compared with disease induction by cyclophosphamide.     

NF-kappa B prevents beta cell death and autoimmune diabetes in NOD mice

Whereas NF-kappaB has potent antiapoptotic function in most cell types, it was reported that in pancreatic beta cells it serves a proapoptotic function and may contribute to the pathogenesis of autoimmune type 1 diabetes. To investigate the role of beta cell NF-kappaB in autoimmune diabetes, we produced transgenic mice expressing a nondegradable form of IkappaBalpha in pancreatic beta cells (RIP-mIkappaBalpha mice). beta cells of these mice were more susceptible to killing by TNF-alpha plus IFN-gamma but more resistant to IL-1beta plus IFN-gamma than normal beta cells. Similar results were obtained with beta cells lacking IkappaB kinase beta, a protein kinase required for NF-kappaB activation. Inhibition of beta cell NF-kappaB accelerated the development of autoimmune diabetes in nonobese diabetic mice but had no effect on glucose tolerance or serum insulin in C57BL/6 mice, precluding a nonphysiological effect of transgene expression. Development of diabetes after transfer of diabetogenic CD4(+) T cells was accelerated in RIP-mIkappaBalpha/nonobese diabetic mice and was abrogated by anti-TNF therapy. These results suggest that under conditions that resemble autoimmune type 1 diabetes, the dominant effect of NF-kappaB is prevention of TNF-induced apoptosis. This differs from the proapoptotic function of NF-kappaB in IL-1beta-stimulated beta cells.     

Astragalus polysaccharides: an effective treatment for diabetes prevention in NOD mice

BACKGROUND: Type 1 diabetes mellitus (DM) is a chronic autoimmune disease that is related to the disequilibrium state of Th1 and Th2 subgroups of helper T lymphocyte (Th) and their cytokines. Astragalus polysaccharides (APS) are bioactive components extracted from one of the traditional Chinese herbs, used to enhance the function of human immune system. OBJECTIVE: To investigate the effects of APS on preventing type 1 DM and Th1/Th2-subtype cytokines, we compared the results of administration of APS and normal saline (NS) on non-obese diabetic (NOD) mice. SUBJECTS AND METHODS: APS or NS was administered to 4-week-old mice at a dose of 2.0 g/kg per day for 10 weeks. At 40 weeks, blood glucose, serum C-peptide (C-P) and GAD antibody were measured; pancreas was examined histologically; the intra-islet lymphocyte infiltration and T lymphocyte subsets in the spleen were analysed; the gene expression of IL-1 beta, IL-2, IL-6, IL-12, TNF-alpha, INF-gamma, IL-4, IL-5, IL-10, TGF-beta, Bcl-2, SOD, Fas and iNOS were measured by RT-PCR. RESULTS: The results showed that APS-administered NOD mice had a lower incidence rate of type 1 DM, lower serum C-P level, better histologic findings of pancreatic islets, and a lower D4+/CD8+ ratio of T lymphocytes from the spleen and the infiltrated islets. RT-PCR analysis showed gene expression levels are lower in IL-1 beta, IL-2, IL-6, IL-12, TNF-alpha, INF-gamma, Fas, iNOS, and higher in IL-4, IL-5, IL-10, TGF-beta, Bcl-2, SOD in the pancreatic tissue from APS-administered NOD mice as compared to the NS group.CONCLUSIONS: These results demonstrated the effects of Astragalus polysaccharides on the prevention of type 1 DM in NOD mice by correcting the imbalance between the Th1/Th2 cytokines.     

Biotransformation of melatonin in human breast cancer cell lines: role of sulfotransferase 1A1

The biologically active melatonin metabolite, 6-hydroxymelatonin (6-OHMel), is conjugated to form 6-hydroxymelatonin sulfate (6-OHMelS). To elucidate the role of the sulfotransferase (SULT) enzyme 1A1, considerably expressed in normal and malignant human breast cells, we measured the formation of 6-OHMelS by ELISA in hormone-dependent MCF-7 and hormone-independent MDA-MB231 (MDA) breast cancer cell lines after stable transfection with SULT1A1. In parent MDA cells, low SULT1A1 mRNA expression was associated with moderate 6-OHMelS formation as determined after application (24 hr) of 0.1 microM 6-OHMel. As expected, overexpression of SULT1A1 in MDA cells resulted in a 2.9- and 110-fold increase in 6-OHMelS in the cytosol and cellular supernatant respectively. Furthermore, 6.3- and 115-fold increases were observed after 0.5 microM, and 12.6- and 101-fold increases after 1 microM 6-OHMel respectively. In MCF-7 cells, because of high basal SULT1A1 expression, only two- to threefold increases in 6-OHMelS were observed after transfection with the enzyme. In total, 866 and 539 pmol/mg protein 6-OHMelS were formed from 1 microM 6-OHMel in SULT1A1 overexpressing MDA and MCF-7 cells, respectively, whereas application of 1 microM melatonin produced only <1% of 6-OHMelS. Possible interactions with the SULT1A1 substrate tamoxifen (tam), an anti-estrogen applied in the therapy of breast cancer, were also studied. A concentration of 1 microM tam increased 6-OHMelS formation by approximately threefold in the presence of 1 microM melatonin or 1 microM 6-OHMel respectively. However, no alterations were detected after application of 1 microM 4-hydroxy-tamoxifen. In summary, we demonstrate the importance of SULT1A1 for the biotransformation of 6-OHMel in human breast cancer cells. Our data further suggest that tam can modulate melatonin biotransformation.     

PD-1 deficiency reveals various tissue-specific autoimmunity by H-2b and dose-dependent requirement of H-2g7 for diabetes in NOD mice

Although many autoimmune diseases are associated with particular HLA/H-2 haplotypes, the mechanisms through which specific HLA/H-2 haplotypes afford autoimmune susceptibility remain enigmatic. Here, we analyzed the effects of the diabetes-associated (H-2(g7)) and an antidiabetogenic (H-2(b)) H-2 haplotypes in NOD mice deficient for programmed cell death-1 (PD-1, Pdcd1), a unique model of type 1 diabetes that confers complete penetrance and rapid onset of the disease. NOD-H2(b/b)Pdcd1(-/-) mice were completely protected from diabetes, confirming that H-2(g7) is indispensable for diabetes even in the absence of PD-1. However, NOD-H2(b/b)Pdcd1(-/-) mice developed autoimmune inflammation in multiple tissues including peripheral nerves, stomachs, and exocrine tissues, demonstrating that autoreactive T cells are generated in the context of H-2(b). These autoreactive T cells damaged target tissues only in the absence of PD-1, confirming that PD-1 deficiency unravels the hidden autoimmune susceptibility of the strain by reducing the threshold of T cell activation. Transfer experiments revealed that CD4 T cells are the effector cells of neuritis, and nerve-infiltrating CD4 T cells are strongly deviated toward Th1. Interestingly, neuritogenic T cells were also generated in the context of H-2(g7), in sharp contrast to the strict requirement of H-2(g7) for diabetes. In addition, 60% of the NOD-H2(b/g7)Pdcd1(-/-) mice developed diabetes, suggesting that H-2(b) does not dominantly suppress diabetes and that H-2(g7) induces diabetes in a dose-dependent fashion.     

The role of autoimmunity in gastroenterology

Crohn's disease (CD) is an immune-mediated chronic intestinal disorder thought to be the result of an aggressive immune response to a subset of enteric bacteria in a genetically predisposed host. Numerous environmental factors are apparently involved in disease pathogenesis. Impaired ability of CD patients to control the gut microflora is associated with defects in the production of some antibacterial compounds (cryptdins) by epithelial cells. In addition, there are the defects in cytoplasmic NOD-like receptors which are sensing intracellularly localized bacteria in CD patients. These defects together with the failure to induce autophagy lead to lack of bacterial clearance and subsequently to mucosal immunopathology.     

Association of defective feedback suppressor t cell activity with autoimmunity in nzb mice

A “feedback suppressor T cell” highly dependent on signals from Ly 1 T helper cells for activation is described. The signal from the Ly 1 cell binds to Fc-like receptors on macrophage membranes. The feedback suppressor cell expresses all three Ly antigens as well as the Qa 1 antigen on its surface, is very sensitive to low doses of cyclophosphamide, disappears relatively rapidly after adult thymectomy, and cannot be demonstrated in NZB mice 6 weeks or older.     

Establishment of Theileria-infected bovine cell lines in scid mice

Bovine cells transformed by infection with the protozoan parasite Theileria annulata were inoculated subcutaneously or intraperitoneally into C.B.-17 scid mice. Mice injected subcutaneously developed solid tumours at the injection site, whilst those injected intraperitoneally developed ascites. Schizont-infected cells were found in other tissues: infected cells spread much more easily from the intraperitoneal site. Karyotyping of cells isolated from tumours showed no evidence of transfer of parasites to murine cells. These results show that the scid mouse can be used as a host for Theileria-infected bovine cells.     

Restricted islet-cell reactive T cell repertoire of early pancreatic islet infiltrates in NOD mice

The mechanisms responsible for initiating autoimmune diabetes remain obscure. Here, we describe a method for identifying both the alpha- and beta-chains of the T cell receptor (TCR) from individual pancreatic islet-infiltrating T cells at the earliest stages of disease in nonobese diabetic mice (NOD). Analysis of the TCR repertoire of these early islet infiltrates reveals enrichment for a small subset of TCR sequences. Reconstitution of these TCR in vitro demonstrates that these receptors confer reactivity to islet cells but not to the well characterized autoantigens, glutamic acid decarboxylase (GAD65) and insulin. Thus, autoimmune diabetes in NOD may be initiated by a limited number of antigens distinct from GAD65 and insulin.     

A diet enriched in protein accelerates diabetes manifestation in NOD mice

Diet modifies the development of insulin-dependent diabetes mellitus in animals and in humans. We examined female non-obese-diabetic (NOD) mice, a diabetes-prone mouse strain with 70% spontaneous diabetes incidence and metabolic abnormalities in non-overtly diabetic litters. They were fed a diet containing 55% (n=27) or 15% (n=26) protein, respectively, after weaning. At an age of 30 weeks, non-diabetic NOD mice were submitted to an intravenous glucose tolerance test (0.5 g/kg body weight; blood samples were taken after 2, 4, 8, 10, 15, 20 and 30 min) and to perfusion of the pancreas (stimulation media were Krebs-Ringer-Hepes buffer with 5 mmol/l glucose, 30 mmol/l glucose and 5 mmol/l glucose plus 19 mmol/l arginine). Diabetic mice were removed from the experiment. Serum glucose concentration and body weight were monitored weekly. Food ingestion was checked at an age of 11 weeks. On average, the onset of diabetes was diagnosed in mice on a high-protein diet (19.7±1.3 weeks) 4 weeks earlier than in mice on a low-protein diet (23.5±1.1 weeks;P<0.05). Non-diabetic NOD mice on a high-protein diet showed significantly better glucose tolerance (as determined by the glucose disappearance rate) and mean insulin secretion (at 30 mmol/l glucose). No difference in the serum glucose concentration between non-diabetic mice on the low-protein diet or high-protein diet could be proved. In non-diabetic mice on the high-protein diet the body weight and food ingestion exceeded those of mice on the low-protein diet (P<0.05). High insulin secretion and glucose tolerance in non-diabetic mice may reflect the capacity of beta-cells to adapt; however, beta-cells tend to be destroyed under such circumstances. Thus, a high-protein diet promoted the onset of diabetes, but it did not increase significantly the incidence of the disease.     

Human cell engraftment after busulfan or irradiation conditioning of NOD/SCID mice

Human hematopoietic stem cell (HSC) xenotransplantation in NOD/SCID mice requires recipient conditioning, classically achieved by sublethal irradiation. Pretreatment with immunosuppressive and alkylating agents has been reported, but has not been rigorously tested against standard irradiation protocols. Here, we report that treatment of mice with a single dose (35 mg/kg) of Busilvex, an injectable form of busulfan, enables equivalent engraftment compared to 3.5 Gy irradiation. Mice treated with two doses of 25 mg/kg to reduce busulfan toxicity showed increased chimerism. Busulfan conditioning and irradiation resulted in comparable sensitivity of HSC detection as evaluated by limiting dilution analysis.     

Significant role of genetics in IBD: the NOD2 gene

Inflammatory bowel disease (IBD) clusters within families, suggesting a genetic component to disease pathogenesis. Studies have identified a gene on chromosome 16cen that confers susceptibility to Crohn's disease. The affected gene codes for the NOD2/CARD15 protein, which is involved in the immune system's response to bacterial infection. Multiple mutations have been identified, three of which have been shown to be independently associated with Crohn's disease-arg702trp, gly908arg, and leu1007fsinsC. Taken together, these three variants confer a 15%-20% attributable population risk among cases of familial Crohn's disease, with decreased contribution among the more common sporadic cases of the disease. The presence of an NOD2 risk allele has been shown to be associated with ilial disease as well as an earlier age of disease onset. Further studies are needed to clarify the relationship between IBD genotype and disease behavior.     

The target cell response to cytokines governs the autoreactive T cell repertoire in the pancreas of NOD mice

Aims/hypothesis  The pancreatic beta cell response to cytokines is crucial for the development of type 1 diabetes in the NOD mouse. For example, beta cell production of suppressor of cytokine signalling-1 (SOCS-1) protects against diabetes. This finding and other recent studies indicated that cytokine-stressed beta cells might contribute to disease progression by affecting the pancreatic lymphocyte infiltrate. The aim of this study was to provide insight into how the beta cell influences the pancreas-infiltrating T cell repertoire. Methods  Lymphocytes isolated from Socs1-transgenic (tg) and non-tg NOD mice were analysed by flow cytometry. mRNA and protein levels in pancreatic islets were measured by real-time PCR and immunofluorescence analysis, respectively. Results  The percentages of regulatory T cells, total counts and ratios between infiltrating CD8+ and CD4+ T cells, and the expression of killer cell lectin-like receptor subfamily K, member 1 (NKG2D) on CD8+ T cells did not differ in pancreases from prediabetic Socs1-tg and non-tg NOD mice. However, a striking difference in the percentages of CD8+ T cells specific for glucose 6-phosphatase catalytic subunit-related protein 206–214 was found, showing that SOCS-1 prevents the accumulation of high percentages of self-reactive CD8+ T cells in the pancreas. It was also found that protection from diabetes in Socs1-tg NOD mice correlated with a reduced expression of Cxcl10 mRNA in IFN-γ treated islets. Conclusions/interpretation  This study highlights an important role for the beta cell in the local regulation of the diabetogenic process. By responding to the pro-inflammatory pancreas milieu it strongly influences the islet-reactive T cell repertoire in the pancreas. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorised users.     

CRKL基因对K 562细胞的作用研究

目的：通过研究CRKL基因反义寡核苷酸（AODN）对K562细胞增殖及凋亡的作用。探讨CRKL基因对慢性粒细胞性白血病（CML）发病的影响。方法：应用CRKL基因反义寡核苷酸作用于K562细胞，通过^3H-TdR掺入，流式细胞术，Rt-PCR等方法观察K562细胞形态学，细胞周期，细胞动力学及基因表达等变化。结果：CRKL基因ASODN对K562细胞的增殖有抑制作用。并可诱导K562细胞的凋亡。结论：CRKL基因在CML的发病中可能有重要作用。