Activation of natural killer cells and cytokine production in humans by bacterial extracts (OM-85 BV).

The influence of Broncho-Vaxom (BV) on different immune parameters was investigated in vitro on human peripheral blood mononuclear cells (PBMC). It was found that BV enhances the natural killer (NK) activity of PBMC and increases their spontaneous and phytohemagglutin (PHA)-induced production of tumor-necrosis factor--alpha and interleukin-2 as well as the PHA-stimulated production of interferon-gamma. These immunostimulating actions of BV on NK activity and cytokine production can contribute to the understanding of the enhancement of the body's defense mechanisms against respiratory tract infections.