Objective: To analyze the mechanisms of surrogate tolerogenesis induced by chimeric donors.
Methods: Hematopoietic 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.
Results: On 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).
Conclusion: The 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.
Download full-text PDF |
Source |
---|
We recently reported that a chimeric peptide (GEP44) targeting the glucagon-like peptide-1 receptor (GLP-1R) and neuropeptide Y1- and Y2-receptors decreased body weight (BW), energy intake and core temperature in diet-induced obese (DIO) male and female mice. Given that GEP44 was found to reduce core temperature (surrogate measure of energy expenditure (EE)) in DIO mice, we hypothesized that GEP44 would reduce EE in male and female high fat diet (HFD)-fed rats. To test this, rats were maintained on a HFD for at least 4 months to elicit DIO prior to undergoing a sequential 2-day vehicle period, 2-day GEP44 (50 nmol/kg) period and a minimum 2-day washout period and detailed measures of energy homeostasis.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Department of Neurology, Davis School of Medicine, University of California, 1515 Newton Court, Davis, CA 95618, USA.
We have designed and produced 39 amino acid peptide mimics of the and human acetylcholine receptors' (AChRs) main immunogenic regions (MIRs). These conformationally sensitive regions consist of three non-contiguous segments of the AChR α-subunits and are the target of 50-70% of the anti-AChR autoantibodies (Abs) in human myasthenic serum and in the serum of rats with a model of that disease, experimental autoimmune myasthenia gravis (EAMG), induced by immunizing the rats with the electric organ AChR. These MIR segments covalently joined together bind a significant fraction of the monoclonal antibodies (mAbs) raised in rats against electric organ AChR.
View Article and Find Full Text PDFBiomed Chromatogr
February 2025
Department of Breast and Thyroid Surgery, The First Affiliated Hospital of University of Science and Technology of China, Anhui Provincial Hospital, Hefei, Anhui Province, China.
Phospholipase A2 receptor 1 (PLA2R1) exists important role in membranous nephropathy. In this study, we evaluate a PLA2R1 in a middle-aged rat model of renal function repair to further investigate the molecular mechanisms of membranous nephropathy. We analyzed the PLA2R1 knockout (KO) model and PLA2R1 knock in (KI) model in rats, extending the time to 85 weeks of age.
View Article and Find Full Text PDFProtein Expr Purif
March 2025
Centre des Sciences Du Goût et de l'Alimentation, CNRS, INRAE, Institut Agro, Université de Bourgogne, F-21000, France. Electronic address:
Bitter is one of the five basic taste qualities, along with salty, sour, sweet and umami, used by mammals to access the quality of their food and orient their eating behaviour. Bitter taste detection prevents the ingestion of food potentially contaminated by bitter-tasting toxins. Bitter taste perception is mediated by a family of G protein-coupled receptors (GPCRs) called TAS2Rs.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!