No abstract available.
Adult ; Female ; Graft Rejection/immunology/*prevention & control ; Graft Survival ; *Hematopoietic Stem Cell Transplantation ; Humans ; *Immune Tolerance ; Immunosuppressive Agents/therapeutic use ; Kidney Failure, Chronic/diagnosis/*surgery ; *Kidney Transplantation ; Living Donors ; Siblings ; Time Factors ; *Transplantation Chimera ; Treatment Outcome

OBJECTIVETo investigate whether the fetal immune tolerance induction could replace the HLA typing for hematopoietic stem cell transplantation.

METHODSImmune tolerance of SD rats was induced by injecting host Wistar rats peripheral blood mononuclear cells into yolk sac of the embryo, afterward the mature male offsprings were used as donor. The host female recipients received lethal dose irradiation and bone marrow transplantation(BMT). The Wistar rats transplanted with bone marrow from donor and unrelated SD rats as well as the rats which received radiation alone were used as control. The survival, histopathologically GVHD, the mental status, food and water intake, coat characteristics, activities were observed. Forty days after BMT, autologous and allogenous skin transplantation between donor and recipient rats was performed to observe the engraftment of solid organ.

RESULTSThe survival of the rats received bone marrow grafts from the immune tolerant donor was significantly longer than that of control groups (30 day survival rates were 86.7%, 6.7%, 0%, and 0% respectively), and there was no histopathologically GVHD observed, while in the sham group, the manifestations of GVHD was clearly visible. The skin engraftment rate between the host and the immune tolerant donor was significantly higher than that among non-related rats (84.6% and 0% respectively).

CONCLUSIONThe induction of immune tolerance in embryo can overcome the HLA barrier and provide a good donor for hematopoietic stem cell and solid organ transplantation.

Animals ; Embryo, Mammalian ; immunology ; Female ; Graft vs Host Disease ; immunology ; prevention & control ; Hematopoietic Stem Cell Transplantation ; Histocompatibility Testing ; Immunosuppression ; Male ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; Transplantation Chimera

OBJECTIVETo investigate whether whole tumor cell vaccination strategies in combination with bone marrow transplantation (BMT) can stimulate graft-versus-tumor effect (GVT).

METHODSTwenty-six BALB/c mice were randomly divided into 3 groups: BMT group (group A, n = 10), BMT + vaccination group (group B, n = 10), control group (group C, n = 6). (BALB/c × C57BL/6) F1 mice [CB6F1, H-2K(b/d)] were used as donors. BALB/c mice of group C were only inoculated with Renca cell (2.6 × 10(6)). Mice of group A and B were conditioned with 8 Gy irradiation, followed by infusion by bone marrow cell of CB6F1 mice on day 1, then inoculated with Renca cell (2.6 × 10(6)) on day 8. All mice of group B were immunized subcutaneous on the back with 5 × 10(5) irradiated Renca tumor cells on day 9 and day 16. All mice of group C were inoculated with Renca cell (2.6 × 10(6)) on day 8. In group A and B, all mice were analyzed by fluorescence activated cell sorter (FACS) on day 14, and 28 day after BMT. Mice were killed on day 32 after inoculation with tumor cell and collected blood sample. All tumors were taken out to be weighed and then fixed in 10% buffered formalin, embedded in paraffin, and cut into 5 µm slices. The slices were stained with HE and examined by TdT mediated-dUTP nick end labeling (TUNEL). Liver, skin, intestine, and spleen were biopsied for histopathological examination.

RESULTSThe results of chimera showed that engraftments of group A, B were full donor chimerism, and the chimerism of those remained above 90% and preserved even after 28 days. The tumor weight, tumor volume increment in the group B was lower than group A and C (P < 0.05). The tumor suppressing rates of the group A and B were 54%, 60% respectively. The area ratio of tumor necrosis and apoptosis index (AI) of the tumor in the group B were higher than group A and C (P < 0.05). Graft-versus-host disease was not observed in each group.

CONCLUSIONThe mechanism of GVT after haploidentical allogeneic bone marrow transplantation with tumor vaccination may be the promotion of tumor necrosis and apoptosis.

Animals ; Bone Marrow Transplantation ; immunology ; Cancer Vaccines ; immunology ; Carcinoma, Renal Cell ; immunology ; therapy ; Cells, Cultured ; Disease Models, Animal ; Graft vs Tumor Effect ; immunology ; Kidney Neoplasms ; immunology ; therapy ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Neoplasm Transplantation ; Transplantation Chimera ; immunology

Immune reconstitution is crucially relevant for patients receiving hematopoietic stem cell transplantation (HSCT). This study was purposed to investigate the ability of α-GalCer (α-galactosylceramide), a well-known activator of natural killer T cells (NK-T), to enhance immune and hematological reconstitution. Lethally irradiated BALB/c mice were transplanted with allogeneic C57BL/6 bone marrow cells and splenocytes. α-GalCer was administered immediately after HSCT. After transplantation, the weight, activity, hairs, diarrhea and survival time of mice were observed daily; the blood routine test was performed once weekly; the donor chimeras, amount of mononuclear cells in spleen (MNC) and relative levels of CD3(+), CD4(+), CD8(+), B220(+), CD11c(+), CD40(+), CD86(+) and CD80(+) cells were detected by FACS on day 2, 7, 14, 27, 70 after transplantation. The results indicated that the MNC counts and relative levels of CD3(+) and CD4(+) in group treated with α-GalCer on day 2 after transplantation were higher than those in control group; at the same time, the detected donor chimeras were complete recipient type chimeras, then gradually transformed into donor type, on day 7 - 14 donor chimeras in α-GalCer group were enhanced significantly as compared with control group, on day 27 the chimeras in two groups were complete donor type chimeras thereafter to day 70, the MNC count and relative levels of CD3(+), CD4(+), CD8(+), B220(+), CD40(+), CD86(+) cells in α-GalCer group were obviously higher than those in control group, at the same time, the hematopoietic reconstitution in α-GalCer group was accelerated as compared with control group. It is concluded that the α-GalCer administration after allogeneic bone marrow transplantations accelerates immune and hematological reconstitution.
Animals ; Bone Marrow Transplantation ; immunology ; methods ; Chimera ; Female ; Galactosylceramides ; pharmacology ; Leukocyte Count ; Lymphocyte Activation ; drug effects ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Natural Killer T-Cells ; drug effects ; immunology ; Postoperative Period

The aim of study was to explore the feasibility of quantitative chimerism analysis of regulatory T (Treg) cells using immune sorting coupling short tandem repeat (STR) method. 14 sets of artificial chimera samples were prepared by mixed lymphocytes according to different proportion. The CD4(+)CD25(+) Treg cells were harvested by negative and positive selection of immunomagnetic beads, then the STR polymorphisms of 16 loci in sorted Treg cells was analyzed. The results showed that the DNA amount extracted from sorted Treg cells was fit for STR detection. All STR alleles specific for recipient or donor could be detected and the quantitative results were consistent with theoretic values in over 10% recipient chimeras. But only partial recipient alleles could be detected and the quantitative results were different from theoretic values in less then 1% recipient chimeras. It is concluded that a quantitative chimerism analysis of Treg cell based on immune sorting is established. The sensitivity and accuracy for chimera detection are 1% to 10%, and this method can be used to monitoring hematopoietic chimerism following allogeneic hematopoietic stem cell transplantation.
Chimerism ; Hematopoietic Stem Cell Transplantation ; methods ; Humans ; Immunomagnetic Separation ; T-Lymphocyte Subsets ; immunology ; T-Lymphocytes, Regulatory ; immunology ; Transplantation Chimera ; genetics ; immunology

OBJECTIVETo investigate a non-toxic AdCTLA4-Ig-based protocol for non-myeloablative allogeneic hematopoietic cell transplantation to induce donor-specific tolerance to hind limb allografts in rats.

METHODSFully mismatched, 4 to 8 week old Brown Norway (RT1(n)) and Lewis (RT1(1)) rats were used as cell/organ donors and recipients, respectively. Recipients were treated with AdCTLA4-Ig (5 x 10(9) PFU, day -30, 0, 30), standard immunosuppressive therapy (MP: 10 mg x kg(-1) x d(-1), MMF: 20 mg x kg(-1) x d(-1), RAPA: 0.2 mg x kg(-1) x d(-1);day -33 - 100), soon after total body irradiation (3 Gy, day -30) and donor bone marrow (100 x 10(6), day -30) transplantation (BMT). Thirty days after BMT, chimeric animals received hind limb transplantations. And 100 days after hind limb transplantations, immunosuppressive therapy was changed for low-dosed CsA (8 mg x kg(-1) x d(-1), day 100-), until the allografts were rejected.

RESULTSIn Group C, hematopoietic chimerism was (38.8 +/- 10.6)% at day 0, and was stable (29.3 +/- 11.9)% at 330 days post-BMT. There was no graft versus host disease in both Group C and Group D. When the standard immunosuppressive therapy was stopped and changed for low-dosed CsA, chimeric recipients (Lewis, RT1(1)) permanently accepted (> 200 days) donor specific (Brown Norway, RT1(n)) hind limb allografts in Group C, yet rapidly rejected in Group A (8 +/- 2) d, Group B (18 +/- 3) d and in Group C (20 +/- 2) d. Lymphocytes of graft tolerant animals' demonstrated hyporesponsiveness in mixed lymphocyte cultures in a donor-specific manner in Group C. Tolerant graft histology showed no obliterative arteriopathy or chronic rejection.

CONCLUSIONThe AdCTLA4-Ig based conditioning regimen with donor BMT produce stable mixed chimerism and induce donor-specific tolerance to hind limb allografts.

Abatacept ; Adenoviridae ; Animals ; Graft Survival ; Hindlimb ; transplantation ; Immune Tolerance ; Immunoconjugates ; pharmacology ; Lymphocyte Culture Test, Mixed ; Male ; Random Allocation ; Rats ; Rats, Inbred BN ; Rats, Inbred Lew ; Transplantation Chimera ; immunology ; Transplantation Conditioning ; methods ; Transplantation, Homologous

OBJECTIVETo analyze the mechanisms of surrogate tolerogenesis induced by chimeric donors.

METHODSHematopoietic stem cells (HSCs) from human cord blood were transplanted into fetal rats via intrauterine injection and infused into the liver of the neonatal rats to establish chimeric rat models with human HSCs. Four weeks after birth, flow cytometry was performed to analyze the percentages of human CD45 (hCD45), CD55 (hCD55) and CD59 (hCD59)-positive cells in the peripheral blood cells of the chimeric rats. The distributions of hCD55- and hCD59-positive cells in different hCD45/SSC gating regions were observed. The resistance of the peripheral blood lymphocytes to complements-mediated cytolysis was assessed by complement-dependent cytotoxicity (CDC) test in the chimeric rats and compared with that in control rats. The correlation between CDC and the human complement-regulating proteins in the chimeric rats were analyzed statistically.

RESULTSOn hCD45/SSC gating, the percentages of hCD55- and hCD59-positive cells in hCD45-positives region were (53.69-/+18.23)% and (31.8-/+27.5)%, accounting for (2.0-/+1.32)% and (0.76-/+0.56)% of the total cell population, respectively, which were significantly lower than the cell percentages in the extensive region (t=2.71, P=0.043 and t=3.64, P=0.015). The cytolytic rate of PBLs incubated with normal human serum was (22.32-/+15.10)% in the chimeric rats, significantly lower than that in the non-chimeric rats [(60.7-/+22.65)%, t=4.16, P<0.001). In the chimeric rats, hCD55-positive cell percentage was inversely correlated in the peripheral blood karyocytes the cytolysis rate in CDC (r=-0.679, P=0.031), and positively correlated to hCD45-positive cell percentage (r=0.658, P=0.038).

CONCLUSIONThe hCD45-positives region is the cluster of chimeric human cells expressing human complement-regulating proteins. The peripheral blood lymphocytes from chimeric donor can resist the cytolysis mediated by human complement. The presence of allogenic CD55 and CD59 antigens in chimeric donors may be the basis of surrogate tolerogenesis for xenotransplantation.

Animals ; CD55 Antigens ; blood ; CD59 Antigens ; blood ; Complement System Proteins ; analysis ; Cord Blood Stem Cell Transplantation ; methods ; Female ; Humans ; Leukocyte Common Antigens ; blood ; Male ; Models, Animal ; Pregnancy ; Rats ; Rats, Sprague-Dawley ; Transplantation Chimera ; blood ; genetics ; immunology ; Transplantation Tolerance ; Transplantation, Heterologous

The purpose of study was to evaluate the effect of stopping use of cyclosporine A (CsA) in reversion of donor chimeras of chronic myeloid leukemia (CML) patients relapsed after transplantation. Two CML patients were transplanted with allogeneic peripheral blood stem cells, and relapsed after transplantation, their bcr/abl gene and/or ph1 chromosome showed positive, donor chimeras decreased. For these two CML patients relapsed after transplantation, the use of CsA was stopped immediately, and the patient's body temperature, skin rash, blood picture, liver function and chimeras were planed to observe carefully. The results indicated that acute graft versus host disease (aGVHD) appeared in both patients. A hundred percent (100%) of donor chimeras were then found with bcr/abl gene and/or ph1 chromosome turning to negative in both patients. In conclusion, to stop using of CsA might be effective in the treatment of some CML patients relapsed after transplantation by reversing of donor chimeras and inducing graft-versus-leukemia (GVL) effect accompanied by GVHD.
Adult ; Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Cyclosporine ; therapeutic use ; Graft vs Leukemia Effect ; immunology ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; genetics ; therapy ; Male ; Neoplasm Recurrence, Local ; genetics ; Peripheral Blood Stem Cell Transplantation ; adverse effects ; Transplantation Chimera ; immunology

OBJECTIVETo explore the feasibility of transplanting the skin from chimeric rats to rabbits.

METHODSChimeric rats were produced by transplanting the haematopoietic stem cells (HSCs) from rabbit marrows into fetal rats in uterus and followed by injecting the HSCs into the livers of the rats at newborn stage. After six weeks, the skin from chimeric rats was transplanted to the rabbits. In group A, the skin grafts from chimeric rat donors were transplanted to the HSCs donating rabbits, with the skin from non-chimeric rat to normal rabbits were used as control. In group B, the skin grafts from chimeric and non-chimeric rats were transplanted to the HSCs donating rabbits at the same time. Gross observation and the surviving time of heterogenic-skin graft were observed. The wound healing time was also recorded.

RESULTSIn group A, the surviving time and the wound healing time of non-chimeric grafts were (9.3 +/- 1.8) days and (20.9 +/- 2.1) days, respectively, while those in chimeric grafts were (15.1 +/- 2.6) and (18.5 +/-1.3) days, respectively. In group B, the surviving time and the wound healing time of non-chimeric grafts were similar to those of group A. Compared with those in non-chimeric grafts, the surviving time of chimeric grafts in both groups were prolonged (P < 0.01), and the wound healing time shortened (P < 0.05 or 0.01). Most of the wounds healed quickly after rejection of chimeric grafts, while the wounds with non-chimeric grafts were re-opened with exudation and some necrotic tissue.

CONCLUSIONImmunologic tolerance for skin graft can be induced by the skin from chimeric donors, which can prolong the surviving time of skin grafts and shorten the wound healing time.

Animals ; Immune Tolerance ; Male ; Myeloid Progenitor Cells ; transplantation ; Rabbits ; Rats ; Rats, Sprague-Dawley ; Skin Transplantation ; immunology ; Transplantation Chimera ; immunology ; Transplantation, Homologous

Child ; Graft Survival ; HLA Antigens ; genetics ; immunology ; Hematopoietic Stem Cell Transplantation ; Humans ; Polymerase Chain Reaction ; Tissue Donors ; Transplantation Chimera ; genetics ; Transplantation Conditioning ; methods ; Transplantation, Homologous ; immunology