HIV (Human Immunodeficiency Virus) is a lentivirus (a retrovirus that replicates slowly) that causes Acquired Immunodeficiency Syndrome (AIDS). HIV has been classified into two types: HIV-1 and HIV-2. HIV-1 was the first to be discovered and was previously referred to as LAV and HTLV-III; it is more pathogenic and more infectious, and it accounts for the majority of HIV infections worldwide.
HIV-1 pseudovirus contains neutralizing antigens of the virus and has the ability to infect cells. When a sample exhibits neutralizing activity, its capacity to infect cells is diminished after exposure to the pseudovirus. By measuring the luciferase expression in each well with a multifunctional plate reader and comparing the value of the test sample well to that of the pseudovirus control group, one can determine whether the sample has neutralizing activity and calculate the sample’s effective potency. The neutralizing antibody titer is the reciprocal of the antibody dilution when 50% of the pseudovirus is inhibited.
