| In the top panel can be seen a viral particle of human immunodeficiency virus at high power in this electron micrograph. It is budding from a cell surface. In the lower panel an HIV virion demonstrates the rod-shaped electron dense core. The components of the virion provide a means for testing for presence of the virus. Antibody is made to outer membrane components such as gp120, and this forms the basis of the standard ELISA test. The p24 antigen from the core can also be detected by the p24 assay. |