("Giant Cells"). Dysfunctional multicellular clumps formed by cell-to-cell fusion. Cells infected with HIV may also fuse with nearby uninfected cells, forming balloonlike giant cells called syncytia. In test tube experiments, these giant cells have been associated with the death of uninfected cells. The presence of so-called syncytia-inducing variants of HIV has been correlated with rapid disease progression in HIV-infected individuals.

a cell that is formed through the fusion of multiple cells, resulting in a multinucleate mass of cytoplasm within the boundaries of a single cell. Syncitial: cell membranes are not present to separate nuclei.

giant cells formed by the fusion of an HIV-infected blood cell with one or more uninfected ones. T cell: white blood cell critical to the immune response. Among these are CD4+ T cells and CD8+ T cells. The "T" stands for the thymus, where T lymphocytes mature. (See also lymphocyte.)