Cystatin C levels in sera of patients with human immunodeficiency virus infection. A new avidin-biotin ELISA assay for its measurement.
A solid-phase enzyme-linked immunosorbent assay (ELISA) for determining human serum cystatin C is described. In 50 normal samples, cystatin C concentration was 1247 +/- 224 micrograms/L (mean +/- SD) which is in agreement with previously reported levels. Serum levels of cystatin C and beta 2-microglobulin (beta 2-M) were investigated in a time-course study during the development of human immunodeficiency virus (HIV) infection. We found a persistent and uniform increase in the beta 2-M concentration (2762 +/- 1239 micrograms/L). In contrast to beta 2-M, on the basis of cystatin C levels, we found two distinct populations, one of which demonstrated an increased concentration (1620 +/- 618 micrograms/L). Interestingly a second group (21% of patients) exhibited an initial significant decrease in cystatin C concentration with a mean value of 377 (range 55-850) micrograms/L, followed by an increase. The biphasic pattern of cystatin C serum, a major cysteine proteinase inhibitor, during the course of HIV infection suggests a possible role for these proteinases (or proteinase inhibitors) in the development of this syndrome.
Collé
A
A
INSERM U 133, Centre de Recherche en Biologie Cellulaire Humaine, Toulouse, France.
Tavera
C
C
Prévot
D
D
Leung-Tack
J
J
Thomas
Y
Y
Manuel
Y
Y
Benveniste
J
J
Leibowitch
J
J
D000293:Adolescent; D000328:Adult; D001360:Avidin; D015415:Biomarkers; D001710:Biotin; D002648:Child; D015891:Cystatins / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods* / Q000706:statistics & numerical data; D005069:Evaluation Studies as Topic; D005260:Female; D015658:HIV Infections / Q000097:blood* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013997:Time Factors; D001613:beta 2-Microglobulin / Q000378:metabolism
D015415:Biomarkers; D015891:Cystatins; D001613:beta 2-Microglobulin; D001360:Avidin; D001710:Biotin