Red cell antigens: Structure and function

Abstract

Landsteiner and his colleagues demonstrated that human beings could be classified into four groups depending on the presence of one (A) or another (B) or both (AB) or none (O) of the antigens on their red cells. The number of the blood group antigens up to 1984 was 410. In the next 20 years, there were 16 systems with 144 antigens and quite a collection of antigens waiting to be assigned to systems, pending the discovery of new information about their relationship to the established systems. The importance of most blood group antigens had been recognized by immunological complications of blood transfusion or pregnancies; their molecular structure and function however remained undefined for many decades. Recent advances in molecular genetics and cellular biochemistry resulted in an abundance of new information in this field of research. In this review, we try to give some examples of advances made in the field of ‘structure and function of the red cell surface molecules.’

Complement serves as a switch between CD4+ T cell–independent and –dependent RBC antibody responses

“…Excluding the well-established ABO(H), I, and other carbohydrate RBC antigens, the vast majority of clinically relevant blood group antigens (e.g., Kell, Kidd, Duffy) are proteins or glycoproteins that are thought to lack fundamental biochemical properties of T cell-independent antigens (12). Rather, these non-carbohydrate blood group antigens have been uniformly thought to induce antibody responses through RBC alloimmunization represents a significant immunological challenge for patients requiring lifelong transfusion support.…”

Antibody‐mediated immunosuppression can result from RBC antigen loss independent of Fcγ receptors in mice

“…Unfortunately, as antibody provided the only mechanism of selectively removing HEL from HOD RBCs, we cannot rule out the potential impact of antibody remaining on the cell surface on antibody formation. While proteolytic cleavage allowed HEL to be selectively removed in vitro , many proteins are sensitive to protease, which could impact RBC circulatory half‐life, interactions with immune cells or other RBC changes that may influence the overall immune response to HOD, precluding the use of this approach to examine the potential impact of HEL antigen levels on anti‐HOD formation. HOD founders that express different levels of HOD, as recently described for KEL, will ultimately be needed to begin defining potential antigen threshold requirements for a productive immune response against the HOD antigen.…”

The role of the Kidd-antibodies in posttransfusion reactions

“…Antigens of the Kidd system are detected only on RBCs and kidney [2,3]. Th ey are carried by an integral membrane glycoprotein, which transports urea through the RBC's membrane [4]. Jka antigen is known as urea transporter UT-B (synonyms: UT3, UT11) [5].…”

“…Uloga Kidd-antitela u posttransfuzijskim reakcijama A Ljubinka I. Nikolić 1 , Emina S. Čolak 2 , Saša A. Kadija 1 , Tatjana Ž. Ilić-Mostić 3 , Nenad N. Mladenović 4 , Srđan Z. Marković 5,6 , Dragana A. Kastratović 6…”