In 2008, Voskuhl, together with Dr. Stefan Gold et al., published a study that revealed the effects of treating men with MS with a 10g gel containing 100 mg testosterone. Based upon the shift in cellular and chemical composition, particularly a decrease in IL-2 cell production, an increase in production growth factor TGFβ1, a decrease in CD4+ T cells, and an increase in NK (natural killer) cells, it was found that testosterone may play an important role in immunomodulation and neuroprotection.[12]