Flow cytometric analysis of in vitro proinflammatory cytokine secretion in peripheral blood from multiple sclerosis patients

The cytokines, interferon-γ (IFN-γ), tumor necrosis factor-α (TNF- α), and interleukin-2 (IL-2) are important endogenous proinflammatory proteins and have been linked to disease activity in multiple sclerosis. In this study, we use flow cytometric methodology to compare the secretion of IFN-γ, IL-2, and TNF-α from peripheral blood-derived T cells of multiple sclerosis patients to the secretion in healthy controls. The percentages of IFN-γ, IL-2, and TNF-α secreting cells are not significantly different between multiple sclerosis patients and controls. However, the TNF-α secreting CD3 cell percentage is correlated with the IFN-γ and IL-2 secreting CD3 cell percentages in multiple sclerosis patients. In the controls, only the TNF-α secreting CD3 cell percentage is correlated with IFN-γ. These findings show that correlated secretion of cytokines occurs in multiple sclerosis and suggest that concerted intercytokine interactions may play an important role in the disease.