direct identification

indirect identification

Produce chemokines and form cell infiltration dominated by mononuclear cells

CD8 CTL

CD4 TH1, TH17

The pre-existing antibodies in the recipient's body bind to the antigen, activating the complement and coagulation systems, leading to vascular coagulation.

ABO/RH blood type incompatibility between donor and recipient

The recipient has repeated blood transfusions, is pregnant, or has had some type of transplant in the past

Cytotoxicity of CD8 Tc

CD4 Th-mediated delayed-type hypersensitivity

Activating complement (same as hyperacute rejection)

Cytotoxicity of specific antibodies or effector cells on microvascular endothelial cells, leading to vascular damage

Chronic delayed-type hypersensitivity induces macrophages to secrete smooth muscle cell growth factors, leading to smooth muscle hyperplasia, arteriosclerosis, etc.

Degenerative changes in tissues and organs

Occurs within days to 2 months after transplantation

After 100 days, 20-70% of patients develop cGVHR

HLAI class gene matching (A, B, C)

HLA II gene matching (DP, DQ, DR)

Rule out the possibility of pre-produced anti-donor antibodies in the recipient

CD40-CD40L, B7-CD28, etc.

PD-1, CTLA4, etc.