• Childhood Kidney Diseases
• /
• v.12 no.1
• /
• pp.23-29
• /
• 2008

Kidney allograft transplantation is the most effective method of renal replacement for end stage renal disease patients. Still, it is another kind of 'disease', requiring immunosuppression to keep the allograft from rejection(allograft immune reaction). Immune system of the allograft recipient recognizes the graft as a 'pathogen (foreign or danger)', and the allograft-recognizing commanderin-chief of adaptive immune system, T cell, recruits all the components of immune system for attacking the graft. Proper activation and proliferation of T cell require signals from recognizing proper epitope(processed antigen by antigen presenting cell) via T cell receptor, costimulatory stimuli, and cytokines(IL-2). Thus, most of the immunosuppressive agents suppress the process of T cell activation and proliferation.

• Journal of Chest Surgery
• /
• v.29 no.12
• /
• pp.1293-1298
• /
• 1996

A series of animal experiments has been carried out to investigate the potential antigenicity of the FCS (Fetal Calf Serum) which is commonly used to enhance viability of preserved aortic allograft. Aorti allografts were processed using nutrient media without FCS(control group) or with 10% FCS(study group). After 14 days of 4$^{\circ}C$ cold storage and cryopreservation, antigenic expression of allograft rondothelial cells were studied using immunohistochemical study. To determine antigenicity, level of Anti-MHC class I Antibody, anti-MHC class II antibody and anti-lCAM 1 antibody were measured. There were no stAtistically significant differences in all antigenic expression between control group and study group(p=0. 524 in MHC class I expression, p=0.897 In MHC class II expression, p=0.1305 in ICAM 1 expression). With this result, antigenicity provoking effect of FCS could not be proven. Thus, FCS may not be eliminated from the nutrient media for preservation of aortic allograft due to its proven benefit of cell viability enhancement.

• Korean Journal of Transplantation
• /
• v.28 no.3
• /
• pp.113-120
• /
• 2014

Two-signal models are useful in explaining various types of immune responses. In particular, secondary, so-called costimulatory, signals are critically required for the process of T-cell activation, survival, differentiation, and memory formation. Early studies in rodent models showed that targeting T-cell costimulatory pathways elicits immunological tolerance, providing a basis for development of costimulatory therapeutics in allograft rejection. However, as the classic definition of T-cell costimulation continues to evolve, simple blockade of costimulatory pathways has limitations in prevention of allograft rejection. Furthermore, functions of costimulatory molecules are much more diverse than initially anticipated and beyond T cells. In this mini-review, we will discuss CD137-CD137L bidirectional signals as examples showing that two-signals can be applicable to multiple phases of immune responses.

• Journal of Korean Neurosurgical Society
• /
• v.58 no.2
• /
• pp.101-106
• /
• 2015

Objective : The aim of this study was to explore the immunity in rats transplanted with adipose-derived mesenchymal stem cells (ADSCs) and acellular nerve (ACN) for repairing sciatic nerve defects. Methods : ADSCs were isolated from the adipose tissues of Wistar rats. Sprague-Dawley rats were used to establish a sciatic nerve defect model and then divided into four groups, according to the following methods : Group A, allogenic nerve graft; Group B, allograft with ACN; Group C, allograft ADSCs+ACN, and Group D, nerve autograft. Results : At the day before transplantation and 3, 7, 14, and 28 days after transplantation, orbital venous blood of the Sprague-Dawley rats in each group was collected to detect the proportion of $CD3^+$, $CD4^+$, and $CD8^+$ subsets using flow cytometry and to determine the serum concentration of interleukin-2 (IL-2), tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) and $interferon-{\gamma}$ ($IFN-{\gamma}$) using enzyme-linked immunosorbent assay (ELISA). At each postoperative time point, the proportion of $CD3^+$, $CD4^+$, and $CD8^+$ subsets and the serum concentration of IL-2, $TNF-{\alpha}$, and $IFN-{\gamma}$ in group C were all near to those in group B and group D, in which no statistically significant difference was observed. As compared with group A, the proportion of $CD3^+$, $CD4^+$, and $CD8^+$ subsets and the serum concentration of IL-2, $TNF-{\alpha}$, and $IFN-{\gamma}$ were significantly reduced in group C (p<0.05). Conclusion : The artificial nerve established with ADSCs and ACN has no obvious allograft rejection for repairing rat nerve defects.

• Journal of Veterinary Clinics
• /
• v.22 no.4
• /
• pp.439-443
• /
• 2005

Rejection is one of the life-threatening complications after organ transplantation. An eight-month-old, intact male, mixed breed dog was presented with acute rejection after renal allograft. The heterotopic renal transplantation with bilateral nephrectomy was performed in the dog. The triple drug protocol for immunosuppression was applied for prevention of the acute rejection. Postoperative care was done according to the transplantation protocol of VMTH, Kangwon National University. The dog was euthanized when the serum creatinine concentration exceeded 5 mg/dL followed by tile signs of illness. The transplanted kidney was enlarged. The renal cortex lesions were characterized by necrosis of the renal tubules and the glomeruli. Interstitial lesions were characterized by hemorrhage and severe infiltration of lymphoid cells. Intrarenal arteries showed necrosis of the walls and infiltration of perivascular lymphoid cells. In immunohistochemical (IHC) findings, infiltration of the CD4 and the CD8 positive T lymphocytes was examined. In this case, acute rejection was shown by humoral and cellular immunity on the basis of histopathologic and IHC evaluation.

• Biomedical Science Letters
• /
• v.2 no.2
• /
• pp.211-222
• /
• 1996

The conceptus which are resulted by mating between two genetically non-identical partners can be considered to be an allograft to the mother science which is not rejected by the mother's immunological attack. The present studies have been, therefore, attempted in order to elucidate the mechanism by which protection of the fete-placental allograft, between the C3H/HeJ female mouse and DBA/2 male mouse occurred. For this purpose, firstly systemic immunity was investigated by measuring T and B lymphocytes subsets. Natural killer cell activity in maternal splenic tissue and by observing the effects of pregnancy serums, progesterone and hCG on immune systems. Secondly, local immunity also investigated by measuring T lymphocytes subsets, natural killer cell activity in lymph nodes draining the uterus. The subsets of Thy-1.2$^+$ cells and L 3T4$^+$ cells decreased slightly while the subsets of Ly2$^+$ cell increased significantly compared with those of the control group beyond the mid-gestational stage. The subsets of B cell gradually in-creased from the mid-gestational stage untill delivery. The natural killer cell activity in the maternal splenic tissue significantly increased during the period of 5th to 8th day of gestation. The natural killer cell activity was significantly suppressed by the pregnancy serums and non-pregnant serums compared with those of serum-free group. The treatment of hCG significantly suppressed natural killer cell activity in the dose dependent manner (1 unit/ml-1000 unit/ml) while pro-gesterone increased the natural killer cell activity at phamarcological dose only. In the lymph nodes draining the uterus, the subsets of Thy-1.2$^+$ cells significantly increased during the period of implantation and L3T4$^+$ cell subsets slightly increased during the mid-gestational stage. The subsets of Ly2$^+$ cell increased significantly during the mid-gestational stage, but decreasing slightly be-fore delivery. The natural killer cell activity was significantly elevated after the implantation period in the lymph nodes draining the uterus. The natural killer cell activity of the lymph nodes draining the uterus was higher than those of splenic tissue during the same periods of gestation. It is therefore, concluded that during the pregnancy, the phenomena which the fete-placental allograft has not been rejected and rather protected from the maternal immunological attack might be due to local immune suppression in fete-maternal interface tissues rather than systemic immune suppression. And the subsets of Thy-1.2$^+$ cells and L3T4$^+$ cells mainly contribute to accepting allograft in early stage of pregnancy, while the subsets of Ly2$^+$ cell and the subsets of B cell increased significantly compared with those of the control group beyond the mid-gestational stage, so their role in systemic immunity and local immunity gradually increased from the mid-gestational stage until delivery.

• Childhood Kidney Diseases
• /
• v.12 no.2
• /
• pp.133-142
• /
• 2008

For solid organ transplant, ABO blood type of donor and recipient should be compatible in principle. Recent improvement of immunosuppressant made HLA typing not so important while no-mismatch transplant still shows the longest graft survival. PRA(panel reactive antibody) test is to screen and identify recipients with HLA sensitization. When solid organ transplant is scheduled, cross-match test of donor cell and recipient serum should be performed and positive result of cross-match prohibits transplantation. Donor specific antibody(DSA) test can predict the severity of recipient immune reaction against donor organ. Today's mainstay of allograft immunosuppressant regimen is triple therapy of steroid, calcineurin inhibitor(cyclosporine, tacrolimus), azathioprine or mycophenolate mofetil(MMF). Antibody induction using Thymoglobulin or anti-IL-2 receptor antibody(basiliximab or daclizumab) is frequently practiced as well.

• Journal of Chest Surgery
• /
• v.29 no.11
• /
• pp.1173-1181
• /
• 1996

The causes of degenerative changes in allograft cardiac valves are not well known to this day. Today's preserved allografts possess highly viable endothelial cells and degeneration of allografts can be facilitated by immune reaction which may be mediated by these viable cells. To test the antigenicity of endothelial cells, pieces from aortic wall were obtained from fresh and cryo-preserved rat allograft. Timings of sampling were prior to sterilization, after sterilization, after 1, 2, 7, 14 days of fresh preservation and cryopreservation. Endothelial cells were tested by immunohistochemical methods using monoclonal antibodies to MHC class I(MRC OX-18), class II(MRC OX-6) and ICAM-1 antigens. After transplantation of each group of aortic allograft at the subcutaneous layers of rats, population of CD4$^{+}$ T cell and CD8$^{+}$ T cell were analyzed with monoclonal antibodies after 1, 2, 3, 4, 6 and 8 weeks. MHC class I expression was 23.95% before preservation and increased to 35.53~48.08% after preservation(p=0.0183). MHC Class II expression was 9.72% before preservation and 10.13~13.39% after preservation(P=0.1599). ICAM-1 expression was 15.02% before preservation and increased to 19.85~35.33% after preservation(P=0.001). The proportion of CD4$^{+}$ T-cell was 42.13% before transplantation. And this was 49.23~36.8% after transplantation in No treat group (p=0.955), decreased to 29.56~32.80% in other group(p=0.0001~0.008). In all the groups, the proportion of CD8$^{+}$ T-cell increased from 25.57% before transplantation to 42.32~58.92% after transplantation(p=0.000l~0.0002). The CD4$^{+}$/CD8$^{+}$ ratio decreased from 1.22~2.28 at first week to 0.47~0.95 at eighth week(p=0.0001). The results revealed that the expression of MHC class I and ICAM-1 in aortic allograft endothelium were increased but that of MHC class II were not changed, despite the different method of preservation. During 8 weeks after transplantation of aortic allograft, the subpopulations of CD4$^{+}$ T cell were not changed or only slightly decreased but those of CD8$^{+}$ T cell were progressively increased.ely increased.