To find a specific antigen of some diseases, the more likely that the disease is present.
This allows a B cell to bind to a specific antigen.
The blood test looks for a protein, the prostate specific antigen, which can signal cancer.
Hormones in blood samples can produce specific antigens during laboratory tests, for example.
In practice, it can be difficult to ascertain which specific antigens are present in a given test.
Each antibody recognizes a specific antigen unique to its target.
However, the identity of these specific ovarian antigen(s) remains unknown.
These are proteins that target specific antigens and then remember how to combat the antigen.
Like a whole antibody, it is able to bind selectively to a specific antigen.
There is, however, no logical reason why a vaccine for protection against tuberculosis should contain species specific antigens.