Increased serum levels of novel T cell cytokines IL-33, IL-9 and IL-17 in subjects with type-1 diabetes

• All the T cytokines tested were elevated in T1DM patients indicating pan T cell activation.
• No distinct Th polarization could be identified.
• No difference was seen in cytokine levels between those with and without complications.

The role of adaptive immune cytokines in the pathogenesis of type-1 Diabetes Mellitus (T1DM) is well known. Even though reports on the serum levels of both Th-1 and Th-2 cytokines are available, those on newly described T cell cytokines such as IL-17, IL-33 and IL-9 in T1DM are scarce. We therefore measured the serum levels of both T cell polarizing (IL-33 and IL-12) and T cell effector (IFN-γ, IL-4, IL-10, IL-17 and IL-9) cytokines in T1DM subjects with and without microvascular (retinopathy and nephropathy) complications (MVC). All the tested cytokines were significantly elevated in T1DM subjects except for IFN-γ (which failed to attain statistical significance) with no significant difference between those with and without MVC. From the serum cytokine analysis, no apparent Th polarization could be determined for the T1DM subjects.