TY - JOUR
T1 - Enzyme-linked immunosorbent assay for antigens of Coccidioides immitis
T2 - Human sera interference corrected by acidification-heat extraction
AU - Wack, Elizabeth E.
AU - Dugger, Kris O.
AU - Galgiani, John N.
PY - 1988/5
Y1 - 1988/5
N2 - We describe the distortion caused by sera from patients with coccidioidomycosis in an enzyme-linked immunosorbent assay (ELISA) for coccidioidal antigen. In experimental mixtures without exogenous antigen, immune sera produced an antigen-like effect. In contrast, in mixtures with a relatively large concentration of exogenous antigen, immune sera obscured antigen activity. In both circumstances, preparing specimens with an acidification-heat extraction procedure before assay rectified serum interference, and only in specimens with no exogenous antigen was the correction incomplete. Other evidence, including direct measurement of anticoccidioidal antibody after extraction, suggested that the residual antigen-like activity was not from persistent antibody. Incorporating the extraction procedure into the ELISA of clinical specimens, we found antigen activity in nine of 15 specimens. We conclude that acidificationheat extraction of sera improves detection of coccidioidal antigens and that coccidioidal antigens are present in some patients with coccidioidal infection.
AB - We describe the distortion caused by sera from patients with coccidioidomycosis in an enzyme-linked immunosorbent assay (ELISA) for coccidioidal antigen. In experimental mixtures without exogenous antigen, immune sera produced an antigen-like effect. In contrast, in mixtures with a relatively large concentration of exogenous antigen, immune sera obscured antigen activity. In both circumstances, preparing specimens with an acidification-heat extraction procedure before assay rectified serum interference, and only in specimens with no exogenous antigen was the correction incomplete. Other evidence, including direct measurement of anticoccidioidal antibody after extraction, suggested that the residual antigen-like activity was not from persistent antibody. Incorporating the extraction procedure into the ELISA of clinical specimens, we found antigen activity in nine of 15 specimens. We conclude that acidificationheat extraction of sera improves detection of coccidioidal antigens and that coccidioidal antigens are present in some patients with coccidioidal infection.
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M3 - Article
AN - SCOPUS:45449125293
SN - 0022-2143
VL - 111
SP - 548
EP - 559
JO - The Journal of Laboratory and Clinical Medicine
JF - The Journal of Laboratory and Clinical Medicine
IS - 5
ER -