ABSTRACT
BACKGROUND:Bone marrow mesenchymal stem cel s and al ogenic bones are commonly used as seed cel s and scaffolds, respectively, for constructing tissue-engineered cartilage through in vitro co-culture. The loose body of the knee joint can survive in the articular cavity for a long time, and maintain certain characteristics of cartilage tissues. Therefore, the articular cavity can provide a good environment for the growth and development of chondrocytes. OBJECTIVE:To investigate the effect of bone marrow mesenchymal stem cel s co-cultured with al ogenic bone in the articular cavity. METHODS:Bone marrow mesenchymal stem cel s were isolated from five newborn New Zealand white rabbits. One adult New Zealand rabbit was enrol ed to prepare al ogenic bone for co-culture with bone marrow mesenchymal stem cel s. Afterwards, bone marrow mesenchymal stem cel s and al ogenic bone composites were cultured in the articular cavity (intracavitary culture group) or in vitro as in vitro culture group, respectively;the normal cartilage tissues grew in the articular cavity as control group. Cel s were observed by hematoxylin-eosin staining and type II col agen immunohistochemistry staining at 4, 8 and12 weeks of culture. RESULTS AND CONCLUSION:At 12 weeks culture, hematoxylin-eosin staining showed:in the control group, chondrocytes arranged tightly and directional y with red stained cytoplasm and cartilage matrix as wel as blue nuclei;in the intracavitary culture group, the scaffold was mostly absorbed and chondrocytes grew into the scaffold in a certain direction with smaller shape, while cytoplasm and cartilage ma trix were red stained, blue nuclei appeared;in the in vitro culture group, abundant chondrocytes proliferated in a disordered arrangement. Immunohistochemistry staining showed:the absorbance ( A) values in the intracavitary culture group showed a continuous increase, but no obvious change was in the other two groups. Moreover, at 4, 8 and 12 weeks of culture, A values in the control group and intracavitary culture group were significantly higher than that in the in vitro culture group (P0.05). These results suggest that the tissue-engineered cartilage can be constructed by bone marrow mesenchymal stem cells co-cultured with allogenic bone under in vitro and in vivo environment, especially in the articular cavity.
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AIM: To explore the mechanism of the nitric oxide (NO) synthesis induced by human C5b-9 complex in glomerular mesangial cells(MC) of rats. METHODS: The MC of rats were cultured and stimulated with human complement C5b-9 complex to induce TNF? and IL-1?. At the same time, several parameters related to NO synthesis were measured at 3 h, 6 h and 24 h after C5b-9 stimulation. The effects of monoclonal antibodies against TNF? and IL-1? on NO synthesis were examined in this system. RESULTS: TNF? concentration in supernatant from MC in C5b-9 group was higher than that of control group at 6, 24 h after stimulation with C5b-9 complex and reversed by adding anti-TNF? McAb. C5b-9 complex didn't stimulate the release of IL-1? in same system. In addition, the expression of iNOS mRNA in MC was observed at 3 h after stimulation with C5b-9. Levels of iNOS mRNA expression and cGMP in MC and NO - 3/NO - 2 in supernatant from MC in C5b-9 group were higher than those in control group at 6, 24 h after C5b-9 stimulation, these changes were also reversed by adding monoclonal antibody against TNF?. CONCLUSION: C5b-9 complex could induce iNOS mRNA expression at 3 h after C5b-9 stimulation, and the synthesis of NO at 6, 24 h was related to TNF? released from cultured MC of rats by C5b-9 complex to a certain extent.
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AIM: To investigate the effects of FK506 on anti-glomerular basement membrane(GBM) nephritis in rats. METHODS: Anti-GBM nephritis model was elaborated by rabbit anti-rat GBM antibody injection in SD rats in this study. The rats were divided into three groups: FK506 treated group(0 5 mg?kg -1 ?d -1 , sc), untreated nephritis control group and normal control group. FK506 was administered daily six hours after injection of anti-GBM IgG. All the rats were observed urinary protein at the 4th day, the 14th day and the 21st day. At the same time, the kidney specimens were collected, and T cell transforming function was also monitored. RESULTS: Rats injected with rabbit anti-GBM Ab developed heavy proteinuria by 4 days, and serum creatinine and serum urea appeared which kept on the rising. Glmerular hypercellularity, crescents, and protein casts were observed in nephritic rats. By electron microscopy, the thickening of GBM and loss of foot processes were seen. T cell transforming function was higher than normal. But, all pathological changes obviously turned for the better in FK506 treated group. CONCLUSION: FK506 could inhibit the progression of rat anti-GBM nephritis.
ABSTRACT
AIM:To study the effect of human complement C 5b～9 complex on nitric oxide(NO) synthesis of glomerular mesangial cells (MC). METHODS: First, the human complement C 5b～9 complexes were isolated and glomerular MC of rats were cultured. Second, the MC were stimulated with C 5b～9 complex and changes of metabolism products of NO(NO 3 and NO 2) in MC culture supernatant at 6,24 and 48 hours after C 5b～9 stimulating were detected. Moreover, cGMP levels in cultured MC were also measured. RESULTS: NO 3/NO 2 contents from culture supernatant and cGMP levels in MC were increased parallelly after C 5b～9 complex stimulation. Further, NO synthesis was inhibited by L-NG-nitro-arginine-methylester(L-NAME). CONCLUSION: NO synthesis of rat glomerular MC was incerased by human complement C 5b～9 stimulation.