Cd 55 Immunohistochemistry Biopsy Tissue

This test is used to diagnose PNH and quantify PNH clones in blood. PNH may be associated with hemolytic anemia, leukopenia, thrombocytopenia and aplastic anemia. This method uses expression of CD55/59 on erythrocytes and the more sensitive fluorescent aerolysin (FLAER) on granulocytes/monocytes. Complement decay-accelerating factor, also known as CD55 or DAF, is a protein that, in humans, is encoded by the CD55 gene. This gene encodes a glycoprotein involved in the regulation of the complement cascade. Binding of the encoded protein to complement proteins accelerates their decay, thereby disrupting the cascade and preventing damage to host cells. Antigens present on this protein constitute the Cromer blood group system (CROM). Alternative splicing results in multiple transcript variants. The predominant transcript variant encodes a membrane-bound protein, but alternatively spliced transcripts may produce soluble proteins.