Which antigen is known to adsorb onto the red cells of adults?

The Leb antigen is a recognized structure that can adsorb onto the surface of red blood cells in adults. It is part of the Lewis blood group system and is notable for its interaction with red blood cells. In healthy adults, the presence of Leb on red blood cells occurs when Lewis antigen is produced primarily by the secretion of certain body fluids, allowing it to coat RBCs.

While the A, B, and H antigens are intrinsic to the blood group system and are genetically determined, they do not adsorb onto red blood cells in the same way. Instead, they are inherent components of the red blood cell membrane based on an individual's genotype. The O antigen, being a part of the ABO blood group, also does not have the same property of adsorption as the Leb antigen. Lastly, the AB designation does not refer to an antigen that can adsorb; rather, it encompasses both A and B antigens present on the red cells of individuals with this blood type.

Understanding the unique property of the Leb antigen in this context highlights its distinction and relevance within clinical lab settings, particularly in serologic testing and compatibility assessments.