A RVIEW ON HIV DIAGONOSTIC TEST BY Ms.AFSATH. B (Reg no ) Ms.AGATHA.K (Reg no ) Ms.LABEEBA MIRSANA.A.M (Reg no ) Ms.MUHSINA.T.V (Reg no ) UNDER THE GUIDENCE OF Mr.KARTHIKEYAN.N, M.PHARM Mr.RONALD PETER, M.PHARM ASSISTANT PROFESSORS DEPARTMENT OF PHARMACEUTICS MALI KDEENAR COLLEGE OF PHARMACY SEETHANGOLI,BELA,KASARAGOD
ABSTRACT HIV is a retro virus- infect CD4 cells of human immune system AIDS is a leading factor of death Undetectable Progression of disease towards AIDS vary with age Accurate & specific method is necessary to detect the infection in early stage HIV diagnostic test ELISA, western blot, Agglutination tests, Immuno-chromatographic strip tests, nucleic acid based test, PCR, Gel electrophoresis
AIM AND OBJECTIVES early diagnosis & treatment for HIV individuals, infants & labour women Sensitivity and specificity Screening of donated blood [r] of vertical HIV transmission from pregnant women to baby Sero-status via Ab testing Entry point for HIV prevention & care intervention Majority test are based on detecting of Abs in serum Tests are also available that use whole blood, dried blood spots, saliva and urine Ab tests ELISA and Western blot tests
INTRODUCTION Diagnostic tests are foundation of successful health care system Molecular DT- patient gene-mutation Markers from host & virus Types of HIV; HIV-1 & HIV-2 Infected individual-cellular & humoral response ART/ HAART & ARD Window period time between initial HIV infection & ability of diagnostic tests to detect infection Ag & Ab tests viral load test NAT Bio-markers
REVIEW OF LITERATURE 1.Bernard M. Branson, MDand et al, 2014: conducted a nonsystematic review of the literature in 2009 to assess the performance of FDA-approved HIV diagnostic assays and their use in combination for the laboratory diagnosis of acute and established HIV-1 infection. 2.Dr Daskalakis is assistant professor at the New York University, 2010: Newer technologies in HIV testing, including third-generation enzyme immunoassays (EIAs) that detect anti-HIV IgM and IgG antibodies, fourth- generation combination EIAs that detect both anti-HIV antibodies and HIV p24 antigen, and nucleic acid– based testing for HIV RNA, have markedly reduced the interval between infection and detection of infection. Rapid diagnostic tests including assays for IgG and IgM anti-HIV antibodies have high sensitivity and specificity. 3.Stefano Butto and et al, Dec : Reviewed that HIV diagnostics have been essential in detecting and monitoring infection, and their use contributed to save countless numbers of lives. Conventional methods for HIV testing, based on detection of HIV-specific antibodies, have been improved over time, gaining in sensitivity and specificity. New rapid kits, which require very few amount of different body fluids and that can determine the presence of HIV antibodies in few minutes are being developed.
DISCUSSION 1. Simple/Rapid test it takes less than 10 minutes 4 types Agglutination assay Flow through membrane assay(membrane immune concentration tests ) Lateral flow membrane assay Comb/dipstick assay 2. Over the counter tests
3.MAGI ASSAY FOR HIV indicator cells are used a green flourescent protein is used as an indicator gene activity is weak and little β-galactosidase is produced (very little to detect) 4. IMMUNO-CHROMATOGRAPHIC STRIP (ICS) TESTS patient’s blood specimen+ signal reagent development of a line on the membrane--- +ve It take less than 15 minutes commercial diagnostic tests main serological target for the detection of HIV infections is based on antibody reactivity to the envelope trans-membrane protein: gp41 for HIV-1 and gp36 for HIV-2. trans-membrane protein ( highly immunogenic&elicits a strong &sustained Ab response in individuals)
5.ELISA take 2-3 hrs detect specific HIV Ab Most efficient test 2 types Screening test -to screen units of blood&blood products Supplemental test-performed on serum sample reactive in screening test antigen capture viral antigen or antibody, using a solid-phase assay system Viruse containing test sample is added to the well& after allowing the time for protein to bind the Ab & wash the well & add 2 nd Ab Ag & Ab ELISA
6.WESTERN BLOT TESTS detect Ab to specific HIV protein-separated on nitrocellulose paper. 9 viral characteristic band can be detected on western blot with HIV sera Immuno precipitation Immuno blot method
7.Fourth feneration HIV tests detects both HIV Ab& p24 Ag also known as HIV combo assay p24 antigen can be detected approximately 14 days before infection used to differentiate between HIV 1& HIV 2 has the potential to reduce the window period
8.POLYMER CHAIN REACTION detection of viral nucleic acid comprises of three steps; 1.Melting of the double stranded DNA template 2.Annealing of the oligo nucleotide primers to the template 3.Extension of the primers by the thermostable DNA polymerase. 9.ELECTROPHORESIS of fragment isolation based on attraction of that fragment to an electric pole. To separate DNA fragments based on their respective sizes through DNA sample DNA ladder
CONCLUSION infected with HIV should be referred for medical care by a provider with experience and expertise treating HIV disease diagnostic problems, which cannot be resolved with serological methods, are usually cleared using methods for direct detection of HIV infection. rapid testing kits require very few amount of different body fluids determine the presence of HIV antibodies in few minutes are being developed determination of both HIV specific p24 antigen and the antibodies has been recently introduced The standard method of diagnosing HIV infection in adults is ELISA and Western blot immunoassays tests for detecting antibodies.