A and B antigens which have the potential to cause agglutination in certain cases are called agglutinogens. But, as far as I know, H antigen cannot give rise to agglutination. So can it be said that H antigen also is an agglutinogen?
H antigen is a precursor for
B antigens, and
hh (recessive) individuals do not express this antigen. See Bombay blood group. This is an example of epistasis. Since
H antigen is present in all
O blood groups, transfusion from any of these to an
hh individual will cause a haemolytic reaction. Anti-H antibodies are agglutinins and have been referred to as agglutinins in the scientific literature.
The fairly strong anti-H agglutinins present in 'Bombay' and 'para-Bombay' individuals (see 5.5.6) are generally accompanied by anti-A and anti-B, neither of which can be separated from the anti-H specific antibodies.
Schenkel-Brunner, Helmut. Human blood groups: chemical and biochemical basis of antigen specificity. Springer Science & Business Media, 2000. e-Book ISBN: 978-3-7091-6294-1