Infectious bronchitis virus (IBV) poses a severe threat to the poultry industry and causes heavy economic losses worldwide. Vaccination is the most effective method of preventing infection and controlling the spread of IBV, but currently available inactivated and attenuated virus vaccines have some disadvantages. We developed a chimeric virus-like particle (VLP)-based candidate vaccine for IBV protection. The chimeric VLP was composed of matrix 1 protein from avian influenza H5N1 virus and a fusion protein neuraminidase (NA)/spike 1 (S1) that was generated by fusing IBV S1 protein to the cytoplasmic and transmembrane domains of NA protein of avian influenza H5N1 virus. The chimeric VLPs elicited significantly higher S1-specific antibody responses in intramuscularly immunized mice and chickens than inactivated IBV viruses. Furthermore, the chimeric VLPs induced significantly higher neutralization antibody levels than inactivated H120 virus in SPF chickens. Finally, the chimeric VLPs induced significantly higher IL-4 production in mice. These results demonstrate that chimeric VLPs have the potential for use in vaccines against IBV infection.
Animals ; Antibodies, Viral/blood ; *Chickens ; Chimera/genetics/immunology ; Coronavirus Infections/prevention & control/*veterinary/virology ; Female ; *Immunity, Innate ; Infectious bronchitis virus/genetics/*immunology ; Influenza A Virus, H5N1 Subtype/genetics/immunology ; Injections, Intramuscular/veterinary ; Mice ; Mice, Inbred BALB C ; Neuraminidase/genetics ; Poultry Diseases/*prevention & control/virology ; Recombinant Fusion Proteins/genetics/immunology ; Spike Glycoprotein, Coronavirus/genetics/*immunology ; Vaccines, Synthetic/administration & dosage/genetics/immunology ; Vaccines, Virus-Like Particle/administration & dosage/genetics/*immunology ; Viral Proteins/genetics

This research was to construct the lentiviral expression vector for anti- p185(erbB2) mouse/human chimeric antibody and to determine the expression of the chimeric antibody gene in 293T cells transfected with this vector. The genes (vL and vH) coding light and heavy chain of variable regions of anti-p185(erbB2) mAb and the constant regions of human IgG1 (kappa and gamma1) were cloned with PCR method. The target genes were assembled by three-primers PCR method to obtain the chimeric light chain (L) and the chimeric heavy chain (H). Both chains inserted into the down stream and upper stream of IRES gene of the plasmid pVAX1/IRES respectively. We digested the plasmid pVAX1/ H-IRES-L with endoenzyme and subcloned H-IRES-L into the lentiviral vector pWPI. The enzyme digestion and sequence analysis showed that the lentiviral expression vector pWPI/H-IRES-L was constructed correctly. Then, it was transfected into 293T cells and after 48h, GFP protein expression in 293T cells were detected by fluorescent microscope and the chimeric antibody expression was detected by RT-PCR and direct ELISA. The results showed that after 293T cells were transfected with recombination plasmid, both light and heavy chains of the chimeric antibody genes could express together. The chimeric antibody expressed could bind to p185(erbB2) specifically. This research may lay a sound foundation for further study of anti-p185(erbB2) engineered antibody.
Animals ; Antibodies, Monoclonal ; biosynthesis ; genetics ; Cell Line ; Chimera ; Cloning, Molecular ; Humans ; Lentivirus ; genetics ; metabolism ; Mice ; Receptor, ErbB-2 ; biosynthesis ; genetics ; immunology ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology ; Transfection

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 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

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

To study if rhesus haploidentical hematopoietic stem cell transplantation model can be established by non-myeloablative conditioning, parent monkeys were used as donors, offspring monkeys were used as recipients. The recipient monkeys received a nonmyeloablative conditioning consisting of fludarabine, cyclophosphamide, total body irradiation and rabbit anti-human thymocyte globulin. Cyclosporine, mycophenolate mofetil and anti CD25 antibody were used for GVHD prevention. Donor mobilized peripheral blood stem cells were transplantated on day 0. Hematopoietic recovery, chimerism level, GVHD were assessed regularly. The results indicated that hematopoietic recoveries in all 4 cases were observed within 8 days after transplantation. Donor hematopoietic chimerism could be induced in all cases, chimerism analysis showed full donor chimerism (FDC) in case 3 and 4, and II to III grade GVHD developed on day 12 and 14. In case 1, only low level donor chimerism was detected on day 7, and transplantation rejection happened eventually. Unfortunately, kidney failure happened in case 2 after conditioning and died several days later, chimerism analysis showed 50% donor rate on day 7. It is concluded that the rhesus transplantation model was successfully established by nonmyeloablative conditioning for striding over the MHC barrier. This rhesus monkey model would provide a basis for future research.
Animals ; Antibodies, Monoclonal ; administration & dosage ; Cyclosporine ; administration & dosage ; Graft vs Host Disease ; blood ; etiology ; prevention & control ; Hematopoietic Stem Cell Transplantation ; adverse effects ; methods ; Interleukin-2 Receptor alpha Subunit ; immunology ; Karyotyping ; Macaca mulatta ; Models, Animal ; Mycophenolic Acid ; administration & dosage ; analogs & derivatives ; Time Factors ; Transplantation Chimera ; blood ; genetics ; Transplantation Conditioning ; methods ; Transplantation, Homologous

The purpose of this study was to transplant neonatal rat with human cord blood Lin(-) cells to test the possibility of this xenograft model. The Lin(-) cells were purified from human cord blood (CB) using negative selection strategy based on different lineage-specific antigens. The Lin(-) cells were injected into the liver of neonatal rats using a microinjector at an average of 5 x 10(5) cells for each. Peripheral blood (PB) and spleen were collected at 2,4 and 8 weeks after injection. Flow cytometry was performed to detect human cells in the rat PB, PCR was used to detect human cells in PB as well as spleen. The results showed that a definite proportion of human cells existed in peripheral blood of chimeric rat and the human specific beta2 microglobulin gene fragments were detected in spleen genomic DNA of chimeric rat. It is concluded that human/rat chimera model can be developed with neonatal rats. Human/rat xenograft model may provide a useful and convenient method for human hematopoietic stem cell assay in vivo.
Animals ; Animals, Newborn ; Cord Blood Stem Cell Transplantation ; DNA ; genetics ; Flow Cytometry ; Humans ; Leukocyte Common Antigens ; blood ; Polymerase Chain Reaction ; Rats ; Rats, Sprague-Dawley ; Spleen ; metabolism ; Transplantation Chimera ; blood ; genetics ; immunology ; Transplantation, Heterologous ; beta 2-Microglobulin ; genetics

OBJECTIVEThe purpose of this study is to construct plant expression plasmid containing the gene encoding chimera SBR-CT delta A1.

METHODSThe target gene fragment P2, including the gene-encoded chimera SBR-CT delta A1 (3,498-5,378 bp), was obtained by standard PCR amplification. The PCR products were ligated with pGEM-easy vector through TA clone to form plasmid pTSC. The plasmid pTSC and plasmid pPOKII were digested by restricted endonuclease BamHI and KpnI, and the digested products were extracted and purified for recombination. Then the purified P2 and plasmid pPOKII were recombined by T4 DNA ligase to form recombinant plasmid pROSC; inserting bar gene into the plasmid and form pROSB plasmid. The recombined plasmids were isolated and identified by restricted endonuclease cutting and Sanger dideoxy DNA sequencing.

RESULTSP2 gene was linked to pPOKII plasmid and formed recombinant plasmid pROSC. The DNA sequence and orientation were corrected. And bar gene was inserted into pPOSC and form recombinant plasmid pROSB.

CONCLUSIONPlant expression vector pROSC and pROSB containing the gene encoding chimera SBR-CT delta A1, which may provide useful experiment foundation for further study on edible vaccine against caries have been successfully constructed.

Adhesins, Bacterial ; genetics ; Animals ; Chimera ; genetics ; Cloning, Molecular ; Dental Caries ; prevention & control ; Gene Transfer Techniques ; Genetic Vectors ; Lipoproteins ; genetics ; Lycopersicon esculentum ; genetics ; metabolism ; Plasmids ; genetics ; Rabbits ; Recombinant Proteins ; biosynthesis ; genetics ; Recombination, Genetic ; Streptococcal Vaccines ; genetics ; immunology ; Streptococcus mutans ; genetics ; immunology ; Vaccines, DNA ; genetics

In order to research the prophylactic effect of cyclosporine A (CSA) and mycophenolate mofetile (MMF) on GVHD in mice with H-2 haploidentical nonmyeloablative bone marrow transplantation, a murine model was established by using of C57BL/6J mouse as donor and (C57BL/6J x BALB/C) F(1) mouse as the recipient. The recipient mice were given CSA + MTX or CSA + MMF for prophylaxis of acute GVHD (aGVHD). The survival rate, hematopoietic recovery, and morbidity and mortality of aGVHD were observed for 50 days after transplantation. The results showed that typical aGVHD developed in the transplanted mice without prophylactic treatment during 22 to 25 days after transplantation. The morbidity of aGVHD was 75% (15/20), 40% (8/20) and 30% (6/20) and mortality was 100% (15/15), 62.5% (5/8) and 50% (3/6) respectively in unprophylactic group (control), CSA + MTX and CSA + MMF groups. In conclusion, CSA and MTX reduce the morbidity and mortality of aGVHD in mice with haploidentical nonmyeloablative bone marrow transplantation, and the effect of CSA + MMF is better than that of CSA + MTX.
Animals ; Bone Marrow Transplantation ; immunology ; Cyclosporine ; therapeutic use ; Graft vs Host Disease ; mortality ; prevention & control ; H-2 Antigens ; genetics ; Hematopoiesis ; Immunosuppressive Agents ; therapeutic use ; Male ; Mice ; Mice, Inbred C57BL ; Models, Animal ; Mycophenolic Acid ; analogs & derivatives ; therapeutic use ; Transplantation Chimera