Amino Acid 489 Is Encoded by a Mutational “ Hot Spot ” on the p 3 Integrin Chain : The CA / TU Human Platelet Alloantigen System
نویسنده
چکیده
A new platelet alloantigen, termed CA, has recently been implicated in a case of neonatal alloimmune thrombocytopenia (NATP) in a Filipino family in Canada. Maternal antiCA serum reacted with glycoprotein (GP) llla and maintained its reactivity after removal of high mannose carbohydrate residues from GPllla. The monoclonal antibody (MoAb) AP3 partially blocked binding of anti-CA to GPllla, suggesting that the CA polymorphism is proximal to the AP3 epitope. Platelet RNA polymerase chain reaction (PCR) was used to amplify the region of GPllla cDNA that encodes this region of the protein. DNA sequence analysis showed a G A nucleotide substitution at base 1564 that results in an arginine (Arg) (CGG) glutamine (Gln) (CAG) polymorphism in amino acid (AA) 489. Further analysis of PCR-amplified genomic DNA from 27 normal individuals showed that AA 489 is encoded by a mutational “hot
منابع مشابه
Amino acid 489 is encoded by a mutational "hot spot" on the beta 3 integrin chain: the CA/TU human platelet alloantigen system.
A new platelet alloantigen, termed CA, has recently been implicated in a case of neonatal alloimmune thrombocytopenia (NATP) in a Filipino family in Canada. Maternal anti-CA serum reacted with glycoprotein (GP) IIIa and maintained its reactivity after removal of high mannose carbohydrate residues from GPIIIa. The monoclonal antibody (MoAb) AP3 partially blocked binding of anti-CA to GPIIIa, sug...
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