Novel diagnostic screens type 1 diabetes (IDDM)

Abstract

The present invention features methods for diagnosing insulin-dependent diabetes mellitus (IDDM) in a test subject, for example a subject at risk of developing IDDM, which involve detecting hyper-responsive Ca 2+ mobilization in cells obtained from the test subject. Hyper-responsive Ca 2+ mobilization can be detected in cells contacted with a stimulatory agent, preferably in cells contacted with a potentiating agent and a stimulatory agent. Methods of the present invention include comparing Ca 2+ mobilization in cells from the test subject to Ca 2+ mobilization in cells from a control subject. The present invention further features kits for use in the detection of IDDM.

We claim:  
     
         1 . A method for diagnosing IDDM in a test subject comprising detecting hyper-responsive Ca 2+  mobilization in cells obtained from the test subject.  
     
     
         2 . The method of  claim 1 , wherein detecting hyper-responsive Ca 2+  mobilization comprises comparing Ca 2+  mobilization in cells obtained from the test subject to Ca 2+  mobilization in cells obtained from a control subject.  
     
     
         3 . The method of  claim 2 , wherein comparing Ca 2+  mobilization comprises contacting the cells with a stimulatory agent to induce Ca 2+  mobilization.  
     
     
         4 . The method of  claim 3 , wherein the stimulatory agent is bradykinin.  
     
     
         5 . The method of  claim 2 , further comprising contacting the cells with a potentiating agent prior to comparing Ca 2+  mobilization.  
     
     
         6 . The method of  claim 5 , wherein the potentiating agent is an inflammatory cytokine.  
     
     
         7 . The method of  claim 6 , wherein the potentiating agent in TNF-α.  
     
     
         8 . The method of  claim 6 , wherein the potentiating agent is IL-1β.  
     
     
         9 . The method of  claim 5 , wherein the potentiating agent is a component of the diabetic milieu.  
     
     
         10 . The method of  claim 9 , wherein the potentiating agent is FFA.  
     
     
         11 . The method of  claim 10 , wherein the potentiating agent is oleate.  
     
     
         12 . The method of  claim 11 , comprising contacting the cells with two potentiating agents prior to comparing Ca 2+  mobilization.  
     
     
         13 . A method of identifying a subject at risk of developing IDDM comprising comparing Ca 2+  mobilization in a test cell sample obtained from the subject to Ca 2+  mobilization in a control cell sample and identifying the subject at risk by detecting a difference in Ca 2+  mobilization in the test cell sample as compared to the control cell sample.  
     
     
         14 . The method of  claim 13 , wherein detecting a difference in Ca 2+  mobilization comprises comparing peak Ca 2+  response in the test cell sample to peak Ca 2+  response in the control cell sample.  
     
     
         15 . The method of  claim 13 , wherein detecting a difference in Ca 2+  mobilization comprises comparing steady state Ca 2+  in the test cell sample to steady state Ca 2+  in the control cell sample.  
     
     
         16 . The method of  claim 13 , wherein the test cell sample and the control cell sample are contacted with an inducing agent to induce Ca 2+  mobilization.  
     
     
         17 . The method of  claim 13 , further comprising contacting the test cell sample with a potentiating agent.  
     
     
         18 . The method of  claim 13 , wherein comparing Ca 2+  mobilization in the test cell sample to Ca 2+  mobilization in the control cell sample comprises comparing an incremental increase in Ca 2+  mobilization in the test cell sample in the presence and absence of potentiating agent to an incremental increase in Ca 2+  mobilization in the test cell sample in the presence and absence of potentiating agent.  
     
     
         19 . The method of  claim 1  or  13  wherein the test subject is a human subject.  
     
     
         20 . A kit comprising a control cell sample, a stimulatory agent, a potentiating agent and instructions for use.