Using a specialized technique called total internal reflection microscopy, the researchers were able to aim light at the cell at an angle which lit only the outermost surface, where HIV assembles. To be sure they were seeing actual viral assembly, they added fluorescent molecules to the Gag protein in the cell, which is essential to viral construction. When the proteins appeared at the surface of the cell, the fluorescence changed color as the molecules packed in more tightly, another indicator that what was being witnessed was in fact viral creation. The scientists continued to observe and record as the virus matured, budded, and finally broke itself free of its host cell. The direct observation of viral creation gives researchers a powerful new tool in understanding viral behavior and life cycle. Having previously relied on inference and indirect observational techniques, this new work may very well change the way virologists approach their research in the future. The video can be viewed here.
