Impact of TGFβ on Differentiation of Macrophages

Abstract

Transforming growth factor beta (TGFβ) is an important cytokine that helps in macrophage differentiation and immune homeostasis in the tissue. This study explored the role of TGFb in the differentiation of macrophages and examined the response of the macrophages differentiated in the presence and absence of TGFβ to proinflammatory and anti-inflammatory stimulus. Macrophages differentiated with TGFβ were found to grow as a dark and round cell. Further, the expression of the synapse and adherence proteins, F4/80 and CD11b were found to be lowered in TGFβ treated macrophages compared to untreated cells. However, TGFβ differentiated macrophages has higher expression of MHCII and CD64 indicating the M2 polarization and better antigen presentation capability of the cells. It has been found that TGFβ differentiated macrophages has over 1000 times over expressed NOS2 to LPS stimulus and at the same time over expressed Retlna to IL4 stimuli. This indicates the controlled inflammation and antiinflammation in the TGFβ treated macrophages compared to untreated cells. The presence of low levels of nitric oxide in the cell supernatant in the TGFβ differentiated macrophages compared to normal macrophages indicate the controlled inflammation. Together this study suggests that TGFβ differentiate macrophages to M2 type with better antigen presenting ability and controlled inflammatory response to the external stimuli. This highlights the role of TGFβ in immune regulation during infection and tissue homeostasis