Search results
Results from the WOW.Com Content Network
The Le gene encodes a fucosyltransferase that adds fucose to type 1 precursor substance (both free in serum and in secretions) to make the Le(a) antigen. The le gene is an amorph. The Lewis antigen produced on free type 1 precursor substance passively adsorbs onto the surfaces or red blood cells. [2]
In the vertebrate immune system, each antibody is customized to attack one particular antigen (foreign proteins and carbohydrates) without attacking the body itself. The human genome has at most 30,000 genes, and yet it generates millions of different antibodies, which allows it to be able to respond to invasion from millions of different antigens.
Random rearrangements and recombinations of the gene segments at DNA level to form one kappa or lambda light chain occurs in an orderly fashion. As a result, "a functional variable region gene of a light chain contains two coding segments that are separated by a non-coding DNA sequence in unrearranged germ-line DNA" (Barbara et al., 2007).
A person can have 2 antigen proteins per genetic-locus (one gene from each parent). When first discovered, identified antigens were clustered, creating groups in which no more than two antigens per cluster were found in a given person. Serotype group "A" consisted HL-A1, A2, A3, A9, A10, A11. Another cluster, "B", contained A7, A8, A12, A13 ...
However, strictly speaking, immunogenicity refers to the ability of an antigen to induce an adaptive immune response. Thus an antigen might bind specifically to a T or B cell receptor, but not induce an adaptive immune response. If the antigen does induce a response, it is an 'immunogenic antigen', which is referred to as an immunogen.
An antibody molecule. The two heavy chains are colored red, blue, and purple. The two light chains green and yellow. See also: The immunoglobulin light chain is the small polypeptide subunit of an antibody (immunoglobulin). A typical antibody is composed of two immunoglobulin (Ig) heavy chains and two Ig light chains.
The I designation stands for isoagglutinogen, another term for antigen. [31] The gene encodes a glycosyltransferase—that is, an enzyme that modifies the carbohydrate content of the red blood cell antigens. The gene is located on the long arm of the ninth chromosome (9q34). [32] The I A allele gives type A, I B gives type B, and i gives type O.
A null allele is a gene variant that lacks the gene's normal function because it either is not expressed, or the expressed protein is inactive. For example, at the gene locus for the ABO blood type carbohydrate antigens in humans, [13] classical genetics recognizes three alleles, I A, I B, and i, which determine compatibility of blood transfusions.