Aquatic Exercise at Thermoneutral Water Temperature Enhances Antitumor Immune Responses

Despite the broad rehabilitative potential of aquatic exercises, the relationship between aquatic exercise and the immune system has not been fully elucidated to date. In particular, there are few specific and delicate immunological approaches to the effect of water temperature on immunity. Thus, we examined the effect of water temperature on immunity during aquatic exercise. The animal tumor model was adopted to examine the impact of aquatic exercise at thermoneutral temperature (TT; 29°C) on immunity compared with aquatic exercise at body temperature (BT; 36°C). Tumor-bearing mice were made to swim in TT water or in BT water for 3 wk and immune cells and their functional activity were analyzed using FACS. Tumor growth was significantly suppressed in mice that exercised in TT than in BT water. The tumor control correlated with the increased number of NK (2-fold), γδT cells (2.5-fold), NKT (2.5-fold), and cytotoxic CD8⁺ T cells (1.6-fold), which play a critical role in anti-tumor immune responses. Furthermore, the functional activity was dramatically improved in the TT group, showing enhanced production of IFNγ in CD8⁺ T cells compared with the BT group. This study demonstrates that aquatic exercise in TT water may improve protective immune responses more effectively than in BT water. Although the effects of water temperature on immune function need further verification in humans, this study suggests that water temperature in human hydrotherapy may be important for improving immune function.

The role of soluble common gamma chain in autoimmune disease / 대한해부학회지

The common gamma chain (gammac) is the central signaling unit for a number of cytokine receptors collectively known as the gammac cytokine receptor family. gammac is critical for ligand binding and signaling by gammac cytokines. gammac cytokine signaling had been thought to be mainly regulated by cytokine-specific receptor alpha chain expression levels with little or no effect by gammac surface levels because gammac expression was presumed to remain unchanged during T-cell activation and development. The extent of gammac cytokine responses is thought to be regulated by cytokine specific receptor subunits and not by the gammac receptor. In contrast to this prevailing view, we have recently reported that gammac itself actively regulates gammac cytokine responses. Interestingly, gammac exerted its regulatory effects not only as a conventional membrane receptor protein but also as a secreted protein whose expression was upregulated upon T-cell stimulation. Here we will review how a soluble form of gammac, which is generated by alternative splicing, regulates gammac cytokine signaling and plays a role in controlling immune activation related to autoimmune disease.