Presence Of Chimerism Research Articles

Is chimerism associated with cancer across the tree of life?

Chimerism is a widespread phenomenon across the tree of life. It is defined as a multicellular organism composed of cells from other genetically distinct entities. This ability to 'tolerate' non-self cells may be linked to susceptibility to diseases like cancer. Here we test whether chimerism is associated with cancers across obligately multicellular organisms in the tree of life. We classified 12 obligately multicellular taxa from lowest to highest chimerism levels based on the existing literature on the presence of chimerism in these species. We then tested for associations of chimerism with tumour invasiveness, neoplasia (benign or malignant) prevalence and malignancy prevalence in 11 terrestrial mammalian species. We found that taxa with higher levels of chimerism have higher tumour invasiveness, though there was no association between malignancy or neoplasia and chimerism among mammals. This suggests that there may be an important biological relationship between chimerism and susceptibility to tissue invasion by cancerous cells. Studying chimerism might help us identify mechanisms underlying invasive cancers and also could provide insights into the detection and management of emerging transmissible cancers.

Cultivar-specific markers, mutations, and chimerisim of Cavendish banana somaclonal variants resistant to Fusarium oxysporum f. sp. cubense tropical race 4

BackgroundThe selection of tissue culture–derived somaclonal variants of Giant Cavendish banana (Musa spp., Cavendish sub-group AAA) by the Taiwan Banana Research Institute (TBRI) has resulted in several cultivars resistant to Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), a destructive fungus threatening global banana production. However, the mutations in these somaclonal variants have not yet been determined. We performed an RNA-sequencing (RNA-seq) analysis of three TBRI Foc TR4–resistant cultivars: ‘Tai-Chiao No. 5’ (TC5), ‘Tai-Chiao No. 7’ (TC7), and ‘Formosana’ (FM), as well as their susceptible progenitor ‘Pei-Chiao’ (PC), to investigate the sequence variations among them and develop cultivar-specific markers.ResultsA group of single-nucleotide variants (SNVs) specific to one cultivar were identified from the analysis of RNA-seq data and validated using Sanger sequencing from genomic DNA. Several SNVs were further converted into cleaved amplified polymorphic sequence (CAPS) markers or derived CAPS markers that could identify the three Foc TR4–resistant cultivars among 6 local and 5 international Cavendish cultivars. Compared with PC, the three resistant cultivars showed a loss or alteration of heterozygosity in some chromosomal regions, which appears to be a consequence of single-copy chromosomal deletions. Notably, TC7 and FM shared a common deletion region on chromosome 5; however, different TC7 tissues displayed varying degrees of allele ratios in this region, suggesting the presence of chimerism in TC7.ConclusionsThis work demonstrates that reliable SNV markers of tissue culture–derived and propagated banana cultivars with a triploid genome can be developed through RNA-seq data analysis. Moreover, the analysis of sequence heterozygosity can uncover chromosomal deletions and chimerism in banana somaclonal variants. The markers obtained from this study will assist with the identification of TBRI Cavendish somaclonal variants for the quality control of tissue culture propagation, and the protection of breeders’ rights.

In planta genetic transformation in pigeonpea: Occurrence and analysis of chimerism in transformants

The recalcitrant pigeonpea was genetically transformed through Agrobacterium-mediated in planta gene transfer method. The agroinfection of pricked cotyledonary embryo axes from 2-day-old germinating seeds resulted in development of 16 cry1Ab PCR positive T0 plants. The transcription of transgene was detected in 11 plants by semi-quantitative RT-PCR. In planta gene transfer method is documented to produce chimeric plants due to transformation of differentiated and meristematic cells resulting in mixture of transformed and non-transformed shoots. The detection of Cry1Ab protein through ELISA in leaf tissues of some branches from a single T0 plant indicated presence of chimerism. Further, accumulation of Cry1Ab at variable levels in different leaf tissues revealed quantitative variation for recombinant protein within a single T0 plant. The distinction of this study pertains to its ability to detect quantitative variation within sectorial chimeras which is not possible through PCR and RT-PCR approaches.

Evidence for Recipient-Derived Cells in Peribiliary Glands and Biliary Epithelium of the Large Donor Bile Ducts After Liver Transplantation.

IntroductionChimerism after orthotopic liver transplantation (OLT) has largely been investigated in intrahepatic cellular constituents. However, little is known about chimerism in the extrahepatic and large intrahepatic bile ducts. Our aim was to evaluate the presence and extent of chimerism after OLT in the peribiliary glands (PBG) and the luminal epithelium of the large donor bile ducts.MethodsFor this study, we examined six extrahepatic and large intrahepatic bile ducts from livers that were re-transplanted. In all cases there was a sex-mismatch between donor and recipient (female donor organ and male recipient), which allowed to discriminate between donor- and recipient-derived cells. Specimens from female to female transplants were used as negative controls and male to male transplants as positive controls. Fluorescence in situ hybridization (FISH) for Y and X chromosomes was performed and the percentage of XY positive cells was determined among biliary epithelial cells. Immunohistochemistry was used to correlate chimerism with histological features.ResultsCholangiocellular chimerism in all studied specimens ranged from 14 to 52%. The degree of chimerism was not associated with biliary damage. Marked chimerism was present at 5 days post-OLT. Ki-67-positivity was detected in 1–8% of the epithelial cells at the time of liver re-transplantation, and this correlated inversely with the degree of chimerism.ConclusionRecipient-derived cholangiocytes are present in the large bile ducts of the donor liver after OLT. The presence of chimerism in the large bile ducts suggests that recipient-derived cells may play a role in biliary regeneration following ischemia-induced injury during OLT.

GENOTYPING OF AB0 AND Rh SYSTEMS BLOOD GROUPS IN PATIENTS AFTER MULTIPLE HEMOTRANSFUSIONS

Introduction. In patients after multiple blood transfusions, the serological determination of ABO and Rhesus blood groups becomes unreliable due to posttransfusion chimerism, i.e., circulation in the blood of two erythrocytes populations – own and donors. To solve this problem helps the genotyping of blood groups. The literature review includes 42 literature sources, including 9 Russian and 33 foreign articles. Materials and methods . The authors typed blood samples of 24 patients with hematological disorders after numerous erythrocyte-containing transfusions. Antigens A and B, Rh D, Rh C/c, Rh E/e were determined by the serological method using monoclonal antibodies anti-A, antiB, anti-D, anti-C, anti-Cw , anti-c, E and anti-e (Moabs) (Hematologist, Russia). The presence of chimerism was established by hemagglutination typing in gel columns ID-Cards «DiaClon ABO / D + Reverse Grouping» and «DiaClon Rh-subgroups + K». The DNA extract was examined by PCR-SSP using commercial primers ABO-TYPE and RH-TYPE (BAG, Germany). Results . In two patients with 50% chimerism with anti-A and anti-B monoclones, the ABO blood group was genotypically identified. Using molecular method presence of Rhesus system antigens was established in 24 patients with 20-95% chimerism for 1-5 antigens. Serological determination of blood groups at 4 months after the cessation of blood transfusions has confirmed all genotyping results. Conclusion . Genotyping is advisable to use to determine the blood groups in patients after numerous erythrocyte-containing transfusions, which allows increasing immunological safety and preventing alloimmunization to clinically significant erythrocytes antigens.

Targeting Cells Causing Split Tolerance Allows Fully Allogeneic Islet Survival With Minimal Conditioning in NOD Mixed Chimeras

Donor-specific tolerance induced by mixed chimerism is one approach that may eliminate the need for long-term immunosuppressive therapy, while preventing chronic rejection of an islet transplant. However, even in the presence of chimerism it is possible for certain donor tissues or cells to be rejected whereas others from the same donor are accepted (split tolerance). We previously developed a nonmyeloablative protocol that generated mixed chimerism across full major histocompatability complex plus minor mismatches in NOD (nonobese diabetic) mice, however, these chimeras demonstrated split tolerance. In this study, we used radiation chimeras and found that the radiosensitive component of NOD has a greater role in the split tolerance NOD mice develop. We then show that split tolerance is mediated primarily by preexisting NOD lymphocytes and have identified T cells, but not NK cells or B cells, as cells that both resist chimerism induction and mediate split tolerance. Finally, after recognizing the barrier that preexisting T cells impose on the generation of fully tolerant chimeras, the chimerism induction protocol was refined to include nonmyeloablative recipient NOD T cell depletion which generated long-term mixed chimerism across fully allogeneic barriers. Furthermore, these chimeric NOD mice are immunocompetent, diabetes free and accept donor islet allografts.

Acquiring homozygous tetraploid germplasm by PEG-mediated protoplast fusion of Rhodiola sachalinensis

To acquire homozygous tetraploid germplasm of Rhodiola sachalinensis. PEG-mediated protoplast fusions were conducted using callus of Rh. sachalinensis as materials. Protoplast fusion products were embedded and cultured in low-density, low-melting-point agar and marked according to the protoplast size, and single-celled sister lines were established to acquire genetically homozygous tetraploid germplasm. R(D) and R(M) of newborn daughter cells or protoplasm, metaphase cells or protoplasm were approximately in line with the formula R(D) = 0.793 7R(M). The change range in diameter of the diploid cells without fusion, two protoplasts fusion product were: 16.7 microm < or = R < 21.3 microm, 21.0 microm < or = R' < 26.8 microm respectively. There is an overlap between the two diameter ranges. The protoplast inoculation density of 1 x 10(4) cells x mL(-1) was appropriate when protoplasts were anchored by low-intensity, low-melting-point agar. Under the conditions of this density, plating efficiency was high and single cell origin of the sister lines microclones grew rapidly, and it was easy to mark the single cell microclones, and separate from each other to subculture. The chromosome counts results showed that chromosome numbers of diploid and tetraploid of single cell lines were 26 and 52, respectively. The result from flow cytometry assay showed that there is no presence of chimerism in single-cell regeneration plantlets. The results of this study provide a scientific basis for polyploid breeding of Rh. sachalinensis.

Transfusion‐associated graft‐versus‐host disease

Transfusion‐associated graft‐versus‐host disease

Microchimerism: a lasting legacy of transfusion?

Microchimerism: a lasting legacy of transfusion?

Does HLA-dependent chimerism underlie the pathogenesis of juvenile dermatomyositis?

Juvenile dermatomyositis (JDM) is a multisystem autoimmune disease that at times resembles chronic graft-vs-host disease. This led us to suggest that nonself cells may play a role in the disease process. In this study we examined the relationship between HLA genotype and the presence of maternally derived chimeric cells in JDM patients and healthy controls, and assessed immunologic activity in the chimeric cells. We identified chimeric cells more often in children with JDM (60 of 72) than in their unaffected siblings (11 of 48) or in healthy controls (5 of 29). The presence of chimerism in the JDM patients, their healthy siblings, and unaffected control children was associated with a HLA-DQA1*0501 allele in the mother (p = 0.011). Further, we show that maternally transferred chimeric T cells are responsive to the host's (JDM childs') lymphocytes (33.75 +/- 8.4 IFN-gamma-producing cells from JDM cells vs 5.0 +/- 1.25 from maternal cells), and that this is a memory response. These combined data indicate that chimeric cells play a direct role in the JDM disease process and that the mother's HLA genotype facilitates the transfer and/or persistence of maternal cells in the fetal circulation.

Extensive chimerism in liver transplants: Vascular endothelium, bile duct epithelium, and hepatocytes

The transplanted liver has been shown to be particularly capable of inducing tolerance. An explanation may be the presence of chimerism. Cells of donor origin have been found in recipient tissues after transplantation of any solid organ. Evidence for the presence of cells of recipient origin within the transplanted liver is very limited. We investigated whether nonlymphoid cells of recipient origin can be found within human liver allografts. Five male patients who received a liver transplant from a female donor and 11 patients who received an HLA-I mismatched liver transplant were studied. We confirmed our observations with two different techniques in combination with double-staining techniques. To identify male cells in female liver transplants, we used in situ hybridization for sex chromosomes. To identify specific HLA class I antigens of recipient origin, we used immunohistochemistry with HLA class I-specific antibodies. Double staining was performed to discriminate different cell lineages and inflammatory cells. Endothelial cells of recipient origin were found in 14 of 16 donor livers. Bile duct epithelial cells of recipient origin were found in 5 of 16 cases. Hepatocytes of recipient origin were seen in only 1 of the 5 studied sex-mismatched donor livers. Our study provides evidence that cells of recipient origin can replace biliary epithelial cells, endothelial cells, and hepatocytes within the human liver allograft. This is consistent with the concept that circulating pluripotent progenitor cells exist, capable of differentiating into endothelial cells, epithelial cells, and hepatocytes. (Liver Transpl 2003;9:552-556.)

Microchimerism frequency two to thirty years after cadaveric kidney transplantation

Understanding the mechanisms of unresponsiveness to allograft is crucial in order to induce longterm specific immune tolerance in organ recipients. An association between persistent microchimerism following allogeneic organ transplantation and donor-specific graft acceptance has recently been proposed. However, the frequency of chimerism and its relevance in long-lasting tolerance are still unclear. We studied 12 long-surviving (20–30 years) and eight recently grafted (2 years) cadaveric kidney transplant recipients for the systemic presence of donor alleles by using allele-specific genomic amplification of DRB1 and H-Y loci. This technique enabled the detection of a 1:4000 to 1:10 000 donor-recipient cell ratio. Among long-term tolerant recipients, microchimerism was observed in only one case in the peripheral blood and in four cases in the skin. These chimeric patients did not differ from others by any clinical or immunologic parameter. In the 2-year tolerant patient group, skin chimerism was evidenced in only one patient who had simultaneously received kidney and liver transplants. No correlation was observed between the presence of chimerism and the number of HLA-DR alleles shared by donor and recipient. This low frequency of microchimerism raises doubts about a major role of chimerism in development of long-lasting specific tolerance following kidney allografting.

Peripheral blood chimerism in renal allograft recipients transfused with donor bone marrow.

Experimental studies have shown that administration of antilymphocyte serum combined with donor bone marrow cells can induce tolerance to allograft tissue. We have initially reported application of these protocols in clinical studies of cadaveric renal allograft recipients who were treated with MALG and donor-specific bone marrow cells. To evaluate the effectiveness of the donor marrow cells in the production of chimerism, a detection method based on 32P-incorporated PCR was established. The 32P PCR was utilized with primers specific for the HLA class II, VNTR (D17S5 and D1S111), and/or Y-chromosome genes to detect the presence of allogeneic chimerism in the recipients. Immediately posttransplant, 26.4% of marrow recipients demonstrated the presence of allogeneic chimerism prior to the marrow transfusion as did 18% in the untransfused controls. In transfused patients, chimerism was detected most frequently during the 1-3-month interval after marrow transfusion (65%), and then diminished to 50-56% at 3-12 months posttransfusion. In the control group the frequency of allogeneic chimerism was gradually decreased and was undetectable in the majority of the patients beyond 3 months posttransplant while marrow-transfused recipients were more likely to have chimeric cells detected consistently beyond 3 months. Rejection episodes were significantly effected by the presence of chimerism in the recipients. Of the transfused patients, 91.3% who demonstrated allogeneic chimerism were rejection-free as compared with 8.7% who experienced at least one rejection episode (P = 0.01). While the presence of allogeneic chimerism in the control group was correlated with rejection-free graft survival, this difference did not reach statistical significance.

Induction of mixed lymphocyte reaction nonresponsiveness after chimeric thymus transplantation

Discussion still continues regarding whether self-tolerance is imparted within the thymus by the thymic epithelial cells (TEC) or by the bone marrow-derived (BMD) dendritic cells and macrophages. Many experiments suggest that BMD cells may be the major cells responsible for inducing tolerance within the thymus. In order to address this question and to see whether thymus chimerism could play a role in establishing transplantation tolerance, we looked in the present experiments at the induction of in vitro tolerance after transplantation of chimeric thymuses. Chimeric thymuses were constructed by injecting T-depleted C3H (H2k) bone marrow into lethally irradiated BALB/c (H2d) mice and were thus composed of TEC of BALB/c and BMD cells of C3H origin, something which was verified with immunoperoxidase staining. Subsequently, chimeric thymuses were transplanted into thymectomized BALB/c mice that were lethally irradiated and reconstituted with T-depleted syngeneic BALB/c bone marrow. In 8 out of 11 BALB/c mice this procedure was successful, and in all chimeric thymus graft-bearing mice, specific tolerance for C3H (H2k) antigens was documented in the mixed lymphocyte reaction (MLR). These experiments thus show that: (1) immunological tolerance can be imparted by BMD cells in the thymus and (2) the presence of chimerism within the thymus could be one of the mechanisms involved in the establishment or maintenance of transplantation tolerance.

Induction of mixed lymphocyte reaction nonresponsiveness after chimeric thymus transplantation

Abstract. Discussion still continues regarding whether self-tolerance is imparted within the thymus by the thymic epithelial cells (TEC) or by the bone marrow-derived (BMD) dendritic cells and macrophages. Many experiments suggest that BMD cells may be the major cells responsible for inducing tolerance within the thymus. In order to address this question and to see whether thymus chimerism could play a role in establishing transplantation tolerance, we looked in the present experiments at the induction of in vitro tolerance after transplantation of chimeric thymuses. Chimeric thymuses were constructed by injecting T-depleted C3H (H2k) bone marrow into lethally irradiated BALB/c (H2d) mice and were thus composed of TEC of BALB/c and BMD cells of C3H origin, something which was verified with immunoperoxidase staining. Subsequently, chimeric thymuses were transplanted into thymectomized BALB/c mice that were lethally irradiated and reconstituted with T-depleted syngeneic BALB/c bone marrow. In 8 out of 11 BALB/c mice this procedure was successful, and in all chimeric thymus graft-bearing mice, specific tolerance for C3H (H2k) antigens was documented in the mixed lymphocyte reaction (MLR). These experiments thus show that: (1) immunological tolerance can be imparted by BMD cells in the thymus and (2) the presence of chimerism within the thymus could be one of the mechanisms involved in the establishment or maintenance of transplantation tolerance.

Tolerance to class I major histocompatibility complex antigens in chicken B cell chimeras. Effect of B cell depletion on transferability of tolerance

B cells from bursa of Fabricius of newly hatched chickens are able to reconstitute the B cell compartment of chemically bursectomized chickens. The resulting B cell chimerism can be detected with monoclonal antibodies against donor B cell alloantigen. Chimeric chickens accept donor-type skin grafts and are unresponsive to donor major histocompatibility complex (MHC) antigens in graft-vs.-host splenomegaly assay and mixed lymphocyte reaction. To study the capability of B cells to induce tolerance to selected MHC antigens, we transplanted class I or total MHC-incompatible bursa cells into cyclophosphamide-treated recipients. The recipients of class I or total MHC-incompatible bursa cells were equally tolerant of donor-MHC antigens. To further analyze the mechanisms of tolerance to class I antigens vs. total MHC, spleen cells from tolerant chickens were transferred to irradiated, histocompatible secondary hosts. The secondary recipients were also unresponsive to bursa cell donor-strain MHC antigens. However, if the chimeric B cells were depleted before the spleen cell transfer, the transfer of tolerance to total MHC was severely inhibited. Instead, most recipients of B cell-depleted spleen cells tolerant of class I antigens were still tolerant of bursa cell donor MHC. Our results indicate differences in the transferability of tolerance to class I antigens vs. entire MHC, although in primary recipients of bursa cells the tolerance is similar. These data suggest that a mechanism that is not dependent on the presence of donor cell chimerism contributes to the maintenance of tolerance to donor class I antigens. The transfer of tolerance to total MHC disparity requires the presence of chimeric cells indicating that donor alloantigen expression is needed for induction of tolerance in the secondary hosts.