|MadSci Network: Immunology|
I'm a bit baffled by the blood type that your friend describes. There are definitely some alternative blood typing systems other that the typical ABO grouping, as summarized in the webpage on Blood Typing Systems Other Than ABO from the BloodBook WWW resource. BloodBook is also a fairly decent reference source for background info. on blood in general, to which you might want to refer your friend.
I suppose it's possible that your friend may have been typed with several different systems, if he traveled internationally in a hazardous occupation, for example. But I'm not familiar with the specification of a blood type using the series of designations that he describes. It would appear that he may be "A-" by the ABO typing system, which leaves I, R, S, & H open for interpretation. The H antigen is a precursor of the AB antigens, as described by the Serum, Cells, & Rare Fluid (SCARF) Exchange webpage referenced from the BloodBook. However, all those who have either an A or B blood type would have to be H as well, so there really wouldn't be any need to specify "H", as opposed to "h", if he is actually A-. "S" could potentially be a typing of the relatively well-known MNS system, as described by the BloodBook & SCARF Exchange websites, and I suppose that "I" could refer to the more obscure Ii system, mentioned on the Blood Typing Systems Other Than ABO webpage. But I really can't fathom any meaning for the "R" designation. "R" is sometimes used in reference to Rh+, with "r" = Rh-, but he appears to be Rh-.
Practically speaking, I would recommend that you have him confirm his ABO system blood type, either A- or otherwise. Even if there is some system utilizing the nomenclature that he describes, it could easily cause confusion in an emergency setting where a transfusion may be necessary, depending on the staff present.
Finally, I came across an organization using the acronym, IRSHA, in searching the WWW for info. on this topic. I don't know what the acronym stands for, but it's used by a group interested in "Channelings from Ascended Masters and The Brotherhood of Light". Depending on this individual's background & personality, you might want to consider the possibility that he may be either interested in this subject or just using it as some sort of a practical joke? I would certainly urge you to exercise caution when investigating this possibility, however, so as not to cause undue insult (& also because my knowledge of this topic may be incomplete).
Best of luck in pursuing this question,
Jeff Buzby, Ph.D.
CHOC Research Institute
MadSci Immunology Network
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