p24 antigen


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Related to p24 antigen: Western blot

p24 antigen

AIDS The 24 kD core antigen of HIV-1, which is linked to clinical AIDS; p24 is the earliest marker of HIV-1 infection, and detectable days to wks before seroconversion to anti-HIV-1 antibody production, detected by ELISA. See CD4:CD8 ratio, HIV, HIV RNA, Reverse transcriptase, Western blot.

p24 antigen

The core protein of the human immunodeficiency virus (HIV). The presence of p24 antigen in the blood is a marker of uncontrolled HIV replication. p24 antigenemia is encountered in the acute retroviral syndrome before host immune response and in advanced acquired immunodeficiency syndrome when the immune system has been destroyed. When p24 antigen is detected in the blood, the HIV viral load is high and the person is highly infectious.
See also: antigen
References in periodicals archive ?
To confirm TLR4 actions on PSP antiretroviral activity, viral load was measured in cell culture supernatant by HIV-1 p24 antigen ELISA after TLR4 inhibition.
Ultrasensitive p24 antigen assay for diagnosis of perinatal human immunodeficiency virus type 1 infection.
Immunohistochemical localization of human immunodeiciency virus p24 antigen in placental tissue.
Of the 2,120 patients whose Western blot was negative or indeterminate, six (0.28%) tested positive for p24 antigen and were found by nucleic acid amplification testing (NAAT) to have HIV viral loads of 10,000 to 100,000 copies/mL.
* During this period, HIV antibody and HIV p24 antigen tests were used to screen all blood donations in South Africa.
Using MT-2 cell line and HIV-1 III B strain, sub toxic concentrations of the extracts were tested for its ability to inactivate cell free HIV and to inhibit HIV replication (Sasaki et al., 2003; Hu and Hsiung, 1989; Nokta and Pollard, 1992).Inhibition of HIV-1 III B growth was monitored by Inhibition of cytopathic effect (CPE) and reduction in HIV-1 p24 antigen (Sasaki et al., 2003; Hu and Hsiung, 1989; Nokta and Pollard, 1992).
Tests for: The presence of HIV 1 and 2 antibodies, which indicate established HIV infection, as well as P24 antigen, which detects a more recent exposure to the HIV virus.
These include the assay for p24 antigen in the absence of antibodies, the sensitive/less sensitive ELISA to determine antibody levels, the BED-CEIA, and more recently, nucleic acid amplification in the absence of antibodies.
There are also two viral tests for HIV that measure the amount of virus in the blood directly: the p24 antigen test and the RNA viral load test.
These tests, using polymerase chain reaction (PCR) or branched DNA (bDNA) technology, offered a more direct method of measuring the treatment effect on the virus in blood, as well as other tissue compartments, compared to measuring p24 antigen or CD4 cells.
Only 2 of these units were identified when the standard HIV p24 antigen immunoassay was used.
"Today's approval is particularly significant since Procleix can be used as an alternative to the currently-licensed p24 antigen test for HIV-1.