OBJECTIVE: To observe the heart anatomic and histological structure of the Banna mini-pig inbred-lined and to provide the morphological data for heart xenotransplantation and breeding transgens pig. METHODS: Ten Banna mini-pigs (12-18 months old) were affused and fixed by common coratid artery. The heart were observed and measured by gross anatomy and histology. RESULTS: There were many similarities between the Banna pig heart and the human heart in anatomy and histology. However, the following differences were observed in the Banna pig heart: 1. Azygos vein directly drew into right atrium cordis. 2. The intercalated disk of cardiac muscle was less than that of human. 3. The Purkinje’s fibre was bigger than that of human. CONCLUSION: On the morphology and histology, the structure of Banna pig heart is similar to the heart of human being. It is possible that Banna minipig heart becomes organ donors for xenotransplantation.
Objective To review the methods of overcoming immunological rejection in xenotransplantation.Methods The strategies of overcoming immunological rejection in xenotransplantation were analyzed and summaried on the basis of an extensive review of the latest l iterature concerned. Results The research development of immunological rejection mechanism and molecular biological technique provided new approaches for overcoming immunological rejection in xenotransplantation. Conclusion It is only a matter of time for xenotransplantation to be appl ied cl inically.
Objective To study whether the porcine endothelial cells (PECs) lines transfected by HLA-G1 can alter the lysis mediated by human peripheral blood mononuclear cell (PBMC) and natural killer cell 92(NK-92). Methods By use of liposomes pack, the pcDNA3.0 eukaryotic expression vector carrying HLA-G1 was transfected into PECs. Using indirect immunofluorescence and RT-PCR assays, the HLA-G1 expression in PECs was detected. The alteration of the lysis mediated by PBMC and NK-92 was detected by51Cr-release assays. Results HLA-G1 expression could be detected in PECs after transfection of HLA-G1 at the levels of protein andRNA. It also could be found that the survival rate of transfected PECs was muchhigher than that of non-transfected PECs, when both of them faced the lysismediated by human PBMC and NK-92.After transfecting the expression of HLA-G1 could be found in the transfected PECs and the lysis mediated by PBMC and NK-92 to PECs decreased obviously (Plt;0.05). Conclusion The PECs- transfected by HLAG1 can decrease the NK lysis, so that it may provide us a new thought to inhibit the xeno-cell-rejection.
OBJECTIVE: To investigate the effect of heterogeneous (swine) acellular dermal matrix (s-ADM) and autologous overthin split-thickness skin (auto-OTS) composite grafting in repair of deep burns at articular sites. METHODS: From May 1999 to April 2000, 19 articular sites in 16 patients, including 14 males and 2 females, were treated. In all the 19 sites of deep burn, the total burn area varied from 2% to 48% and the full-thickness burn area varied from 1% to 35%. After the primary escharectomy (1 to 5 days later) and complete hemostasis, the s-ADM was utilized to cover the exposed articular sites and the auto-OTS was transferred on the surface of sutured s-ADM. The size of s-ADM applied to each patient varied from 25 cm2 to 150 cm2. Regular skin grafting was adopted elsewhere other than the articular site. The survival rate of all skin grafting was evaluated and pathological examination was performed. RESULTS: The survival rate of the composite skin was (90.80 +/- 18.34)%, which was obvious higher than the survival rate of contiguous granulosum skin grafting (P lt; 0.05) and almost the same with that of snip skin grafting(P gt; 0.05). The survived composite skin appeared as smooth and soft as normal skin, and the function of articular site almost recovered with neglectable hypertrophic scar. The pathological examination revealed that the normal cell grew into s-ADM with regularly arranged collagen fiber and neovascularization in the matrix. CONCLUSION: The combination of s-ADM and auto-OTS graft is cheap and effective method to cover wound and minimize hypertrophic scar.
Objective To evaluate the feasibility of poly-L-lactide(PLLA)/porcinederived xenogeneic bone(PDXB) composite as a scaffold for the bone tissue engineering. Methods The film and the scaffold of the PLLA-PDXB composite were respectively prepared by a solution casting method and a solution casting-particle leaching method. The composite film and scaffold were further treated by the surface alkaline hydrolysis. The surface morphology of the composite was observed by the scanning electron microscopy, and hydrophilicity degree of the composite was measured. The OCT-1 osteoblastlike cells were cultured and amplified in vitro as the seeding cells, which werethen implanted on the film and scaffold. The adherence rate, adherence shape,proliferating activity, and growing morphology of the OCT-1 osteoblastlikecells were observed on the film. Results The PDXB particle 50 μm in diameter on average had a similar phase structure to that of hydroxyapatite. But its Ca/P ratio was lower than that of hydroxyapatite. After the surface alkaline hydrolysis, the PDXB particle could be exposed on the surface of the PLLA-PDXB composite. The surface roughness and hydrophilicity of the PLLAPDXB composite were obviously enhanced. The cell adherence rate and the cell proliferation activity of the PLLAPDXB composite were higher than those of the pure PLLA material. The cells tended to grow on the exposed surface of the PDXB particles. The cells seeded on the composite scaffold could migrate to the inside of the composite scaffold and grew well. Conclusion The PLLA-PDXB composite has a good cell affinity, and this kind of composite can hopefullybecome a new scaffold material to be used in the bone tissue engineering.
【Abstract】 Objective To produce a new bone tissue engineered carrier through combination of xenograft bone (X)and sodium alginate (A) and to investigate the biological character of the cells in the carrier and the abil ity of bone-forming in vivo, so as to provide experimental evidence for a more effective carrier. Methods BMSCs were extracted from 2-week-old New Zealand rabbits and the BMSCs were induced by rhBMP-2 (1 × 10-8mol/L). The second generation of the induced BMSCs was combined with 1% (V/W) A by final concentration of 1 × 105/mL. After 4-day culture, cells in gel were investigated by HE staining. The second generation of the induced BMSCs was divided into the DMEM gel group and the DMEM containing 1% A group. They were seeded into 48 well-cultivated cell clusters by final concentration of 1 × 105/mL. Seven days later, the BMP-2 expressions of BMSCs in A and in commonly-cultivated cells were compared. The second generation of the induced BMSCs was mixed with 2% A DMEM at a final concentration of 1 × 1010/mL. Then it was compounded with the no antigen X under negativepressure. After 4 days, cells growth was observed under SEM. Twenty-four nude mice were randomly divided into 2 group s (n=12).The compound of BMSCs-A-X (experimental group) and BMSCs-X (control group) with BMSCs whose final concentrat ion was 1 × 1010/mL was implanted in muscles of nude mice. Bone formation of the compound was histologically evaluated by Image Analysis System 2 and 4 weeks after the operation, respectively. Results Cells suspended in A and grew plump. Cell division and nuclear fission were found. Under the microscope, normal prol iferation, many forming processes, larger nucleus, clear nucleolus and more nuclear fission could be seen. BMP-2 expression in the DMEM gel group was 44.10% ± 3.02% and in the DMEM containing 1% A group was 42.40% ± 4.83%. There was no statistically significant difference between the two groups (P gt; 0.05). A was compounded evenly in the micropore of X and cells suspended in A 3-dimensionally with matrix secretion. At 2 weeks after the implantation, according to Image Analysis System, the compound of BMSCs-A-X was 5.26% ± 0.24% of the totalarea and the cartilage-l ike tissue was 7.31% ± 0.32% in the experimental group; the compound of BMSCs-X was 2.16% ± 0.22% of the total area and the cartilage-l ike tissue was 2.31% ± 0.21% in the control group. There was statistically significant difference between the two groups (P lt; 0.05). At 4 weeks after the operation, the compound of BMSCs-A-X was 7.26% ± 0.26% of the total area and the cartilage-l ike tissue was 9.31% ± 0.31% in the experimental group; the compound of BMSCs-X was 2.26% ± 0.28% of the total area and the cartilage-l ike tissue was 3.31% ± 0.26% in the control group. There was statistically significant difference between the two groups (P lt; 0.05). Conclusion The new carrier compounding A and no antigen X conforms to the superstructural principle of tissue engineering, with maximum cells load. BMSCs behave well in the compound carrier with efficient bone formation in vivo.
It is reported in this paper that defect of chest wall of dogs were repaired by hetcrotransplantation of pig bone. The shape of original chest wail were achieved following operation. Histologic study showed that the grown between trabeculae with immersion that method is not only to have same function of other reparing materials,but there is no rejection.
Objective To investigate the immunological rejection after hepatocyte transplantation for acute liver failure （ALF） in mice．Methods The hepatocytes were isolated from pig，BALB/c and C57BL/6 mice livers were conducted and then transplanted into C57BL/6 mice．CCl4 was used to make ALF mice model．The experimental animals were randomly divided into three groups， including syngenic group，allogeneic group，and xenogenic group．The survival statuses of all the mice were recorded. The alteration of T lymphocyte subsets，immune globulin，and cytokine were determined．Results ①The survival ratio was 8/10，6/10， and 3/10 in the syngenic group， allogeneic group， and xenogenic group， respectively．The survival ratio in the syngenic group was significantly higher than that in the other two groups （P＜0.05）．②The CD4+ and CD8+ T cells of the peripheral blood in the syngenic group did not change significantly on week one after transplantation．The CD4+ T cells in the allogeneic group reached the peak on day 3 after hepatocyte transplantation （P＜0.05）， while CD8+ T cells did not change much in one week．The CD4+ and CD8+ T cells in the xenogenic group increased and reached the peak on day 3 after transplantation （P＜0.05）．③There were no significantly differences of IgM and IgG in the syngenic group among 0.5， 1， and 3 d after transplantation. IgM of the allogeneic group and xenogenic group reached the peak on day 1 （P＜0.05） and IgG reached the peak on day 3 （P＜0.05） after transplantation．④The concentrations of IFN-γ， TNF-ɑ， and IL-2 in the allogeneic group and xenogenic group were significantly higher than those in the syngenic group （P＜0.05）．The concentration of IL-6 of the xenogenic group was higher than that of the other two groups （P＜0.05）. Conclusions CD4+ and CD8+ T cells play an important role in immune response to both allogeneic and xenogenic hepatocyte transplantation， as well as induce humoral immune response early after hepatocyte transplantation．
OBJECTIVE: To investigate the expression and distribution of xenoantigen in intervertebral disk of Chinese banna minipig inbred line, and to study the availability of xenograft transplantation of intervertebral disk. METHODS: Samples of intervertebral disk were collected from six Banna pigs of 8 to 11-month-old. The fixation, embedment and slice were performed. α-Gal specific binding lection (BSI-B4) were used as affinity reagents and affinity-immunohistochemistry assays (SABC methods and DAB stain) were conducted to detect the expression and distribution of xenoantigen (α-Gal). RESULTS: alpha-Gal was found in chondrocyte cell and chondrocyte-like cell in intervertebral disk which have the positive yellow-stained particulate aggradation. There was no stain in the matrix, elastic fiber and collagen fiber. CONCLUSIONS: The distribution of xenoantigen is locally in the tissue of intervertebral disk and its expression is weak. This suggests that the intervertebral disk of Banna pig may be alternative donor for xenotransplantation.
Objective To study efficiency of vascularized bone graft combining with reconstituted bone xenograft (RBX) in repairing bone defect and the expression of the vascular endothelial growth factor (VEGF) in serum. Methods From January 1998 to December 2002, 27 cases of bones defects were treated and randomly divided into 3 groups according to different repair materials: group A (the vascularized bone graft-RBX group, n=9), group B (the vascularized bone graft group, n=10)and group C(the RBX group, n=8). The bone defect repair, the bone healing time and the bone graft resorption were observed by radiograph after 3 months, 6 months and 12 months of operation, and the expression of VEGF in serum was assayed with lumino-enzyme immunoassay before operation and after operative 2 weeks, 4 weeks, 6 weeks and 8 weeks respectively. Results The X-ray films showed that the bonehealing was achieved in 8 cases of group A, in 6 cases of group B and in 3 cases of group C after 3 months; in 1 case of group A, respectively in 3 cases of both group B and group C after 6 months. The bone graft resorption was observed in1 case of group B and in 2 cases of group C after 12 months. The serum VEGF values after operative 2 weeks and 4 weeks were higher than those before operation in all of 3 groups(Plt;0.05), and the VEGF values of groups A and B were higher than that group C(Plt;0.05) after 4 weeks. There were no significant differences (Pgt;0.05) in serum VEGF level between postoperative 6, 8 weeks and preoperation in 3 groups. Conclusion The expression of serum VEGF obviously increase in the early period of bone transplanting, it is value of clinical evaluation of reparative efficiency of bone defect.