reagin
(rē-ā-jĭn, -gĭn 
)
[Ger. Reagin, fr. reag(ieren), to react + -in ]
A type of immunoglobulin E (IgE) present in the serum of atopic individuals that mediates hypersensitivity reactions. SYN: sensitizing antibody.
ABBR: RPR
A nonspecific serological test for syphilis. The RPR titer is elevated in most patients with syphilis (and falsely elevated in some patients with other diseases). The titer decreases or returns to normal after successful eradication of the disease.reaginic,
(rē-ă-jin'ĭk, -gin' )