[Correlation of transplantation tolerance and chimerism induced by allogeneic parabiosis in adult rats].
OBJECTIVE
To induce transplantation tolerance by allogeneic parabiosis in adult rats to explore the relation between chimeras and tolerance.


METHODS
Cyclophosphamide (CP, 100 mg/kg) was intraperitonially administered before and after parabiosis to observe the survival days of parabiotic rats. Grafting skin for each other after separation of parabiosed rats pairs on day 5, 15 and 45 respectively to observe the survival time of skin graft survival. In the same time the percentage of cells of donor origin in the spleen and thymus of recipient rats were determined by FACS. Mixed lymphocyte reaction (MLR) and delayed type hypersensivity (DTH) at day 15 of parabiosis were tested.


RESULTS
Survival days of parabiotic rats were significantly prolonged (P = 0.000 5, MST = 63.5 days). After 15 day of parabiosis, the stable skin transplantation tolerance was established. During the first 15 day of parabiosis, the level of chimerism was increased with time, afterwards the chimerism became relatively stable. DTH and MLR of parabiotic rats on day 15 were donor-specifically suppressed.


CONCLUSIONS
Parabiosis can induce specific transplantation tolerance in both parabiotic DA and LEW rats. There is a positive correlation of chimerism and transplantation tolerance.
Shi
Q
Q
Institute of Urology, Beijing Medical University, Beijing 100034, China.
Xie
S
S
Yu
L
L
D000818:Animals; D006968:Hypersensitivity, Delayed / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology; D010227:Parabiosis / Q000379:methods*; D051381:Rats; D011917:Rats, Inbred Lew; D011919:Rats, Inbred Strains; D016038:Skin Transplantation / Q000276:immunology / Q000401:mortality; D015996:Survival Rate; D013997:Time Factors; D018183:Transplantation Chimera / Q000276:immunology*; D023001:Transplantation Tolerance / Q000276:immunology*