The Public Health Agencies of Canada's National HIV and Retrovirology Laboratories (NHRL) provide a comprehensive range of laboratory science services and expertise related to HIV and emerging retroviruses. Organizations that use these services include laboratories associated with provincial ministries of health, hospital and blood-screening laboratories, and HIV laboratories abroad. The NHRL's core activities are:
The NHRL is comprised of the following laboratories:
The National Laboratory for HIV Reference Services (NLHRS) provides HIV and HTLV (Human T-cell Leukemia Virus I/II) serology and molecular reference services in support of testing programs conducted by provincial ministries of health and the Canadian Blood Services. The laboratory also works closely with the Canadian Association of HIV Laboratory Specialist to ensure that HIV testing in Canada is among the best in the world. The NHLRS provides quality assurance programs to national and international laboratories for HIV viral load testing, and HIV antibody testing. The accuracy of the results submitted by each laboratory is determined with feedback provided to all participating laboratories. The NHLRS also provides expertise and guidance to international communities, assisting with the development and implementation of quality assurance programs in their own countries.
NLHRS is actively involved in the development and optimization of new and innovative technologies (HIV-2 viral load testing, HTLV quantitative testing, optimization and improvement of molecular techniques). It also provides surveillance support for a variety of National epidemiological studies.
The National Laboratory for HIV Genetics (NLHG) performs genetic analysis of HIV for a number of activities including the Canadian HIV/AIDS Strain and Drug Resistance Surveillance Program, (CHSDRSP). Through a collaboration between the NLHG, the Surveillance and Risk Assessment Division, and the provinces and territories, this program monitors and evaluates trends in HIV drug resistance and HIV subtype distribution. The CHSDRSP ensures the quality of HIV diagnostic testing, informs vaccine development, guides antiretroviral selection and facilitates our understanding of HIV transmission patterns.
Additional NHLG activities included administering a national HIV drug resistance quality assurance program, assisting in outbreak investigations with molecular epidemiology services, supporting drug resistance studies, and promoting technology development and transfer through international collaboration.
The NLHG also studies other retroviruses of potential public health significance. The NLHG has evaluated the potential risks associated with porcine endogenous retrovirus (PERV) transmission to possible xenotransplant recipients and continues to study simian foamy virus (SFV) as a marker for potential cross-species transmission of retroviruses from monkeys to humans.
The National Laboratory for HIV Immunology (NLHI) is the national resource centre for flow cytometry based diagnostics of cellular immunological diseases. All activities can be defined as service and method development oriented work in the field of infectious disease reduction and prevention.
Under the service category, the laboratory manages the nationwide CD4 T-cell enumeration external quality assessment programme (EQAP). This EQAP serves all members of the Canadian Clinical Trials Network engaged in drug and vaccines studies in the fight against HIV. Similar EQAP has been developed to support resource-poor countries administering antiretroviral drugs. This international program is called QASI and in addition to the Agency, receives financial support from the World Health Organization, the Centre for Disease Control and Prevention in the United States, the Clinton Foundation and some other agencies. This international initiative supports EQAP for CD4 T-cell counting in remote locations where no commercial EQAP is available.
As part of method research component, NLHI evaluates and develops various HIV surrogate markers and cellular-based assays to help establish early indicators of failure/restoration of the immune competency of individuals living with HIV. NLHI is committed to share knowledge by the providing of expert training and skills build workshops both at home and abroad.
The Viral Evolution and Molecular Epidemiology Unit (VEMEU)
The Viral Evolution and Molecular Epidemiology Unit is involved in several activities strategically positioned to reduce the impact of HIV. Studies include the use of dried blood spots (DBS) for HIV drug resistance genotyping; studying the prevention of mother-to-child transmission of HIV in resource-limited settings, the Polaris seroconversion study and the evaluation of a novel SIV vaccine candidate deleted of all accessory genes. Seroconversion is the progression after initial infection from HIV-negative status to HIV-positive status.
Reference Services Activities:
Quality Assurance Activities:
Surveillance and Outbreak Investigations:
(in collaboration with national epidemiological studies)
There is a need to develop more cost-effective CD4 T-cell counting technologies for resource-limited regions. One challenge is the lack of affordable monitoring systems that function at remote locations in Africa and Asia. Recent advances in light emitting diode (LED) technology are leading the way in developing cost-effective and portable fluorescence microscopes.
Until recently, compact user-friendly flow cytometry was unavailable. NHRL scientists, in cooperation with industry, is developing a battery-powered affordable flow cytometer that requires little in the way of training to perform CD4 T-cell counting at point of patient care at remote locations.
Methods for HIV drug resistance (HIVDR) surveillance are needed as part of the on-going search for effective antiretroviral treatment. This has led the NHRL to evaluate the use of dried blood spots (DBS) for HIVDR genotyping. Studies in Mexico suggest that results obtained from DBS are equivalent to those from plasma. This data therefore indicates that DBS are useful for HIVDR surveillance, especially in countries where specimens might be exposed to severe conditions and delays in processing.
While laboratories may already exist, guidance may be needed for testing algorithms and their application to HIV surveillance. This sometimes requires the exchange of scientific personnel and knowledge. Disruptions such as military conflict can diminish both infrastructure and testing capacity that may have taken years to develop. Laboratories often require assistance and training to rebuild their capacities.
The Worldwide Analysis of resistance Transmission over time of Chronically and acute infected HIV patients (WATCH) program seeks to analyse HIV-1 reverse transcriptase and protease gene sequences from patients from all over the world that have had no previous treatment. The result will be a database on the worldwide transmission of drug-resistant HIV-1. WATCH is also working to build a global collaborative network of researchers involved in HIV resistance, integrating efforts when needed. The National Laboratory for HIV Genetics is one of NHRL's contributors to the WATCH program.
Training and Technical Assistance
NHRL's National HIV Immunology Laboratory offers skills-building workshops and other means to support members of the Canadian HIV Clinical Trial Network to assure consistent quality CD4 T-cell counting across Canada. NHRL is now playing a key international role abroad in skills-building workshops and biotechnology capacity transfer seminars. They are focussed on: (1) technology transfer of T-cell enumeration at a technical level, (2) capacity-building at senior laboratory manager level to establish quality management practices, and (3) introduce the essential elements required to run a national external quality assessment programme (EQAP) that is linked to an international EQAP called QASI. NHRL staff give lectures, technology transfer sessions, and skills-building workshops in Ottawa and around the world in English, French and Chinese to support effective evaluation and monitoring of HIV positive individuals.
NHRL's international collaboration and involvement through:
Contact us at:
Office of the Director
National HIV and Retrovirology Laboratories
100 Eglantine Driveway
Ottawa, ON K1A 0K9