Faculty
- Max Q. Arens, Ph.D., Co-director
- Gregory A. Storch, M.D., Co-director
Staff
Research Personnel
- Katherine Cavaletti
- Magda M. Dwidar
The lab was formed in the fall of 1988 as a support lab for the AIDS Clinical Trials Unit (ACTU), an NIH-funded activity engaged in testing of drugs potentially effective against HIV and the opportunistic infections associated with AIDS. In addition to testing for various virologic markers, a major part of our function was and is to process specimens (mainly blood) for storage and/or shipment to other labs for specialized testing pursuant to ACTU protocols. Over the past 12 years we have expanded our repertoire to include testing of clinical specimens for the diagnosis of HIV infection and prognosis of HIV disease.
As the epidemic and our knowledge of HIV and AIDS have changed, so have the laboratory tests required to support the physicians involved in treating infected patients. The tests that we currently perform are briefly discussed below.
HIV antibody ELISA (Barnes-Jewish Hospital Blood Bank)
This is the "first line" screening assay for antibodies in an adult that may be infected with HIV. With today's assays, antibodies are generally detectable about 21 days after an HIV infection in humans (range of 9 to 34 days). This assay is now performed every day in the Barnes Blood Bank and specimens that are repeatedly positive are sent to the Retrovirus Lab for supplemental testing (e.g., Western blot; see below).
HIV Western blot
An antibody test with very high specificity is required as a supplemental assay when the stakes are high as with HIV. This assay shows the interpreter precisely which (if any) HIV antigens have elicited an antibody response in the patient.
HIV proviral DNA PCR assay
This is a qualitative assay which is capable of detecting very low levels of proviral DNA in infected lymphocytes. This assay is generally used for diagnosis of a neonatal infection, since maternal antibodies from HIV-infected mothers mask the true infection status of the baby. Once a patient is infected with HIV, the DNA PCR assay will always be positive (from about day 16 on).
Viral Load (quantitative HIV RNA assay)
Progression of HIV disease is roughly proportional to the amount of virus circulating in the blood of the infected person. Effective treatment of HIV infection is manifested as a decrease in the viral load. The assay we use is PCR-based and comes in two versions, standard (detection range = 400 to 750,000 copies of RNA/ml) and the ultrasensitive assay (detection range = 40 to 75,000 copies/ml).
HIV Genotype (sequencing of HIV RNA)
Genetic mutations occur in HIV at a very high rate and can result in reduced susceptibility to antiretrovirus drugs if they occur in the gene against which a drug is directed. Thus, since over 20 antiretroviral drugs are FDA-approved, it is important to monitor the development of mutations so that drugs which lose their effectiveness can be replaced with ones that are more effective.
Quantitative HCV RNA
The Retrovirus Lab is diversifying by performing several assays for HCV. The HCV Quant is very similar to the above "viral load" assay for HIV. The detection range of this assay when run on undiluted specimens is 600 to 850,000 International Units/ml. We routinely dilute specimens 1:10 in order to expand the useful range of the assay at the higher end and thus we shift the detection range to 6000 to 8,500,000 IU/ml. Undiluted specimens will be run by special request at the time the test is ordered.
Qualitative HCV RNA
The Qualitative HCV RNA assay is used by physicians to confirm the presence of an active HCV infection in patients with anti-HCV antibodies (i.e., a positive ELISA test) and to assess the efficacy of therapy for HCV. This is the most sensitive test available for HCV RNA and has a lower limit of detection of about 100 IU/ml.
HCV Genotype
We are performing the HCV genotype assay to aid physicians in the prognosis of HCV-positive patients who are being treated with interferon + ribavirin. Patients with type 1 require longer treatment regimens and are less likely to achieve virologic clearance. For this assay we use the PCR-amplified product from the Roche Amplicor assay in an Innogenetics reverse hybridization (RH) assay.
The Retrovirus Lab has carefully saved thousands of specimens over the years and we have taken measures to assure that we can find these specimens when they are needed. We are confident that these specimens are properly preserved and are accessible. Part of the mission of this lab is to foster research related to HIV, HCV and other infectious diseases that may be relevant to the patients infected with these viruses. We have been saving specimens and maintaining databases for this purpose. We will make both available to interested researchers with proper approval from the Washington University Office of Human Research Protection.
Faculty
- Max Q. Arens, Ph.D., Co-director
- Gregory A. Storch, M.D., Co-director
Staff
Research Personnel
- Katherine Cavaletti
- Magda M. Dwidar
The lab was formed in the fall of 1988 as a support lab for the AIDS Clinical Trials Unit (ACTU), an NIH-funded activity engaged in testing of drugs potentially effective against HIV and the opportunistic infections associated with AIDS. In addition to testing for various virologic markers, a major part of our function was and is to process specimens (mainly blood) for storage and/or shipment to other labs for specialized testing pursuant to ACTU protocols. Over the past 12 years we have expanded our repertoire to include testing of clinical specimens for the diagnosis of HIV infection and prognosis of HIV disease.
As the epidemic and our knowledge of HIV and AIDS have changed, so have the laboratory tests required to support the physicians involved in treating infected patients. The tests that we currently perform are briefly discussed below.
HIV antibody ELISA (Barnes-Jewish Hospital Blood Bank)
This is the "first line" screening assay for antibodies in an adult that may be infected with HIV. With today's assays, antibodies are generally detectable about 21 days after an HIV infection in humans (range of 9 to 34 days). This assay is now performed every day in the Barnes Blood Bank and specimens that are repeatedly positive are sent to the Retrovirus Lab for supplemental testing (e.g., Western blot; see below).
HIV Western blot
An antibody test with very high specificity is required as a supplemental assay when the stakes are high as with HIV. This assay shows the interpreter precisely which (if any) HIV antigens have elicited an antibody response in the patient.
HIV proviral DNA PCR assay
This is a qualitative assay which is capable of detecting very low levels of proviral DNA in infected lymphocytes. This assay is generally used for diagnosis of a neonatal infection, since maternal antibodies from HIV-infected mothers mask the true infection status of the baby. Once a patient is infected with HIV, the DNA PCR assay will always be positive (from about day 16 on).
Viral Load (quantitative HIV RNA assay)
Progression of HIV disease is roughly proportional to the amount of virus circulating in the blood of the infected person. Effective treatment of HIV infection is manifested as a decrease in the viral load. The assay we use is PCR-based and comes in two versions, standard (detection range = 400 to 750,000 copies of RNA/ml) and the ultrasensitive assay (detection range = 40 to 75,000 copies/ml).
HIV Genotype (sequencing of HIV RNA)
Genetic mutations occur in HIV at a very high rate and can result in reduced susceptibility to antiretrovirus drugs if they occur in the gene against which a drug is directed. Thus, since over 20 antiretroviral drugs are FDA-approved, it is important to monitor the development of mutations so that drugs which lose their effectiveness can be replaced with ones that are more effective.
Quantitative HCV RNA
The Retrovirus Lab is diversifying by performing several assays for HCV. The HCV Quant is very similar to the above "viral load" assay for HIV. The detection range of this assay when run on undiluted specimens is 600 to 850,000 International Units/ml. We routinely dilute specimens 1:10 in order to expand the useful range of the assay at the higher end and thus we shift the detection range to 6000 to 8,500,000 IU/ml. Undiluted specimens will be run by special request at the time the test is ordered.
Qualitative HCV RNA
The Qualitative HCV RNA assay is used by physicians to confirm the presence of an active HCV infection in patients with anti-HCV antibodies (i.e., a positive ELISA test) and to assess the efficacy of therapy for HCV. This is the most sensitive test available for HCV RNA and has a lower limit of detection of about 100 IU/ml.
HCV Genotype
We are performing the HCV genotype assay to aid physicians in the prognosis of HCV-positive patients who are being treated with interferon + ribavirin. Patients with type 1 require longer treatment regimens and are less likely to achieve virologic clearance. For this assay we use the PCR-amplified product from the Roche Amplicor assay in an Innogenetics reverse hybridization (RH) assay.
The Retrovirus Lab has carefully saved thousands of specimens over the years and we have taken measures to assure that we can find these specimens when they are needed. We are confident that these specimens are properly preserved and are accessible. Part of the mission of this lab is to foster research related to HIV, HCV and other infectious diseases that may be relevant to the patients infected with these viruses. We have been saving specimens and maintaining databases for this purpose. We will make both available to interested researchers with proper approval from the Washington University Office of Human Research Protection.