Urinary evaluation of the balance between soluble interferon-gamma receptor (IFN-γR1) and interleukin-4 receptor (IL-4Rα)

To elucidate the usefulness of the simultaneous analysis of multiple kinds of soluble cytokine receptors in urine specimens, we determined the levels of both the soluble interferon-gamma receptor α chain (sIFN-γR1, Th1-type cytokine receptor) and the soluble interleukin 4-receptor α chain (sIL-4Rα, Th2-type cytokine receptor) in the urine of healthy subjects as reference values and preliminarily applied this method to evaluate patients with diarrhea positive (D+) hemolytic uremic syndrome (HUS) as the diagnostic parameters. The urinary sIFN-γR levels of children were significantly lower than those of adults (p < 0.01, n = 107). On the other hand, there was no significant difference between the urine sIL-4R levels of adults and children. Statistical correlation between sIFN-γR and sIL-4R values was not observed (p = 0.705). On the day of onset of HUS, the urine sIFN-γR levels of the patients (n = 6) with HUS were higher than those of the healthy control group (n = 67) (p < 0.01); however, there was no significant difference in the sIL-4R levels between both groups. The urine evaluation of the balance between the soluble cytokine receptors might be informative for the immune states of HUS patients.