[PDF] antigene p24 quand

What is p24 antigen?

This is a viral protein contained in infected cells, in viral particles, and sometimes free in serum. The p24 antigen is detectable only in very early or very late infections, when antigen exceeds the amount of antibody. Most of the time, in HIV-infected patients, p24 antigen is negative because antibody is in excess.

Can p24 be used as a biomarker?

In this review, we present outcomes of research pertaining to use of p24 as a biomarker including a short history of p24 diagnostics, use of antigen assays for early detection, characteristics of commercial antigen assays, and we discuss reasons why detection of p24 is challenging and complex.

Can a p24 antigen test detect HIV infection after seroconversion?

Antibodies to p24 are produced during seroconversion, rendering p24 antigen undetectable after seroconversion in most cases. Therefore, p24 antigen assays are not reliable for diagnosing HIV infection after its very earliest stages.

What is the cut-off for p24 antigen detection based on ROC analysis?

In this study, the cut-off, selected based on the ROC analysis, is equal to 1.2 × OD 450 nm (0.31 pg/ml). This cut-off corresponds to the LOD for detection of p24 antigen of approximately 0.4 pg/ml. This LOD is 2-fold greater than the LOD estimated based on using the twice the background (negative control) value.