Reduction of human-to-pig cellular response by alteration of porcine MHC with human HLA DPW0401 exogenes.
BACKGROUND
In pig-to-human discordant xenotransplantation, the xenograft can be rejected by a formidable human xenogenic T-cell response, even if the graft has gone through hyperacute rejection or delayed xenograft rejection (acute vascular rejection). We therefore examined, in this study, whether the human-to-pig cellular response could be attenuated through the generation of a transgenic pig for human HLA II.


METHODS
With the technique of microinjection, we produced the HLA DPw0401 transgenic pig. The expression of the HLA DPw0401 gene on peripheral blood mononuclear cells (PBMCs) of the transgenic pig was examined by reverse transcriptase-polymerase chain reaction and flow cytometry. The antigenicity of the transgenic HLA DPw0401 molecule was tested by the HLA DPw0401-primed lymphocyte test reagent. The cellular response was analyzed by xenogenic mixed lymphocyte culture.


RESULTS
The mRNA and protein of HLA DPw0401 were expressed in the PBMCs of the transgenic pig. The PBMCs of the HLA transgenic pig induced a stronger cellular reaction to HLA DPw0401-primed lymphocyte test reagents than the nontransgenic littermate pig (n=7, P<0.01). In direct xenogenic mixed lymphocyte culture with responders from HLA DPw0401(+) humans, the PBMCs from the HLA DPw0401 transgenic pig, as compared with those from the normal pig, induced a lower degree of xenogenic cellular response to human PBMCs (n=4, P=0.08).


CONCLUSIONS
Our preliminary data demonstrated the possibility that the human HLA DPw0401 phenotype can be transferred onto porcine cells through the generation of HLA transgenic pigs and make the PBMCs of humans more tolerant to porcine cells.
Lee
Jang-Ming
JM
Department of Surgery, National Taiwan University Hospital, 7, Chung Shan South Rd., Taipei, Taiwan, Republic of China.
Tu
Ching-Fu
CF
Yang
Pei-Wen
PW
Lee
Kun-Hsiung
KH
Tsuji
Kimiyoshi
K
Tsai
Meng-Kun
MK
Chen
Robert J
RJ
Hu
Chung-Yi
CY
Hsieh
Rong-Phong
RP
Tai
Hao-Chih
HC
Chiang
Bor-Luen
BL
Weng
Chung-Nan
CN
Lee
Yung-Chie
YC
Lee
Chun-Jean
CJ
D000818:Animals; D030801:Animals, Genetically Modified; D006682:HLA-DP Antigens / Q000235:genetics*; D006801:Humans; D007959:Lymphocyte Culture Test, Mixed; D012333:RNA, Messenger / Q000032:analysis; D013552:Swine; D013601:T-Lymphocytes / Q000276:immunology*; D014183:Transplantation, Heterologous / Q000276:immunology*
D006682:HLA-DP Antigens; D012333:RNA, Messenger