ALTERATION IN IMMUNE RESPONSE PATTERN AT T-CELL LEVEL DURING HYPER-THYROIDISM AND HYPOTHYROIDISM CLINICAL CONDITION OF AUTO IMMUNE DISORDER IN CONTEXT TO HEALTHY CONTROL.

The risk of infection in many auto immune diseases especially in thyroid patients has posed a major challenge in control programmes. We undertook this study to identify the high risk groups vulnerable to thyroid disease in the State of Bihar, India. Further, immunological responses were also evaluated in these patients showing high and moderate level of TSH for thyroid to see the immune impairment associated with CD4 and CD8 T cell count. Lymphocytes from these patients were further analyzed for Th1( Interferon gamma) and Th2( interleukin-4) intracellular cytokines using the Cell Quest software on a FACS Calibur flow cytometer. Of the 90 thyroid -positive individuals, fifteen(15) who had shown a higher TSH value( 48.55 or above) were categorised as thyroid patients under hyperthyroidism whereas fifteen(15) patients who had shown a lower TSH value( 0.22- 0.02) were categorised as thyroid patients under hypothyroidism patients. The cellular immune responses were evaluated in 15 Indian Thyroid patients with hyper thyrodism category (n=15) and 15 thyroid patients under hypo-thyroidism category. Further, such immunological responses were also evaluated in VL patients( n=10) patients, HIV cases( n=10) and 10 apparently healthy controls to see the immune impairment especially associated with Thyroid disease. A very high absolute CD3 cell count was observed in thyroid cases under both category segregated based on TSH value compared to HIV and VL patients or controls. No significant difference was observed for CD4 cell count in both categories of thyroid patients, however a reduction in CD4 count was very much apparent than healthy control but it was similar an identical reduced CD4 count observed in VL cases. The CD8+ T cell counts showed varied patterns in higher TSH category of thyroid patients and recorded a higher value whereas it was lower in the thyroid patients showing lower TSH value. All hyper thyrodism patients had higher interferon-gamma( IFN-?) produced in culture supernants compared to Thyroid patients with low TSH range, VL, HIV and healthy control. Apart from it, although level of IL-4 was distinctly higher than control, we observed a lower production of interleukin-4 in thyroid patients compared to VL cases and HIV but thyroid patients under hyper-thyroidism category shown with the elevation in the levels of IL-4 which was about two-fold higher in the thyroid cases with hypo-thyroidism state. In summary, a different immune response for CD8 pattern, IFN-? , and IL-4 was noticed in thyroid patients with hyper thyroid state. Unlike to other diseases investigated ( VL and HIV), there was a significant increase in absolute T-cell count ( CD3+ T cells) under both category of thyroid disease. Further studies need to be done to see the effect of therapy on immunological parameters in these patients. Further studies will be needed to clarify the exact role of peripheral lymphocytes in thyroid patients and whether they could provide a reliable marker of thyroid immune involvement.