BACKGROUND: The chemokine Stromal cell-derived factor 1a (SDF1a, @entity1570 ) is currently under investigation as a biomarker for various @entity299 . The correct interpretation of SDF1a levels is complicated by the occurrence of truncated forms that possess an altered biological activity. METHODOLOGY: We studied the immunoreactivities of SDF1a forms and evaluated the effect of adding a @entity5735 inhibitor in sampling tubes on measured SDF1a levels. Using optimized sampling, we measured @entity5735 activity and SDF1a levels in @entity1 with varying degrees of @entity712 . RESULTS: The immunoreactivities of SDF1a and its degradation products were determined with three immunoassays. A one hour incubation of SDF1a with @entity5735 at 37  C resulted in 2/3 loss of immunoreactivity in each of the assays. Incubation with serum gave a similar result. Using appropriate sampling, SDF1a levels were found to be significantly higher in those @entity712 @entity1 with a severe loss of left ventricular function. @entity5735 activity in serum was not altered in the @entity712 population. However, the @entity5735 activity was found to be significantly decreased in @entity1 with high SDF1a levels. CONCLUSIONS: We propose that all samples for SDF1a analysis should be collected in the presence of at least a @entity5735 inhibitor. In doing so, we found higher SDF1a levels in subgroups of @entity1 with @entity712 . Our work supports the need for further research on the clinical relevance of SDF1a levels in @entity299 .

Circulating Stromal Cell-Derived Factor 1a Levels in XXXX : A Matter of Proper Sampling.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity712 :: ('MESH:D006333', 'Disease') :: ['heart failure'] @entity5735 :: ('1803', 'Gene') :: ['DPP4'] @entity1570 :: ('6387', 'Gene') :: ['CXCL12'] @entity299 :: ('MESH:D006331', 'Disease') :: ['cardiac disease', 'cardiac diseases']
@entity712 :: (MESH:D006333,Disease) :: ['Heart Failure']
