A novel T-cell-defined HLA-DR polymorphism not predicted from the linear amino acid sequence.
Recent investigations have shown that alloreactive T cells are capable of responding to structures defined by specific linear amino acid sequences on class II molecules. In the present study we show that also a polymorphism can be recognized that is not defined by such linear amino acid sequences. Two human T-cell clones, sensitized to DRw13 haplotypes, are described. The description of clone c50 serves to exemplify the first model. This DRB1-specific clone responds to stimulator cells that carry DR molecules, different in their DRB1 first and second hypervariable regions (HV1 and HV2) but identical in their HV3 regions (i.e., DRw13,Dw18; DRw13,Dw19; DR4,Dw10; and DRw11,LDVII). The second clone, c1443, behaves nonconventionally. It responds to DRw13,Dw18; DRw13,Dw19; and DR4,Dw4 stimulator cells, although no specific amino acid sequence is shared between these specificities. The latter pattern of reactivity suggests the existence of a novel polymorphism recognized by alloreactive T cells. This particular polymorphism may also be biologically significant.
Termijtelen
A
A
Department of Immunohaematology and Blood Bank, University Hospital of Leiden, The Netherlands.
van den Elsen
P
P
Koning
F
F
de Koster
S
S
Schroeijers
W
W
Vanderkerckhove
B
B
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal; D002999:Clone Cells; D000939:Epitopes / Q000276:immunology; D006684:HLA-DR Antigens / Q000235:genetics / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D011948:Receptors, Antigen, T-Cell / Q000032:analysis; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000939:Epitopes; D006684:HLA-DR Antigens; D011948:Receptors, Antigen, T-Cell