Differential Expression of Micro-RNAs in Circulating Blood of Chronic Idiopathic Urticaria Patients with Hives

Rationale: Chronic idiopathic urticaria (CIU) is a complicated skin disease with unknown trigger factors.  MicroRNAs (miRs), which are snippets of mRNAs occurring during mRNA degradation, have been shown to be active in cellular regulation.  The goal of this pilot study is to examine whether miRs may be involved in the regulation of CIU or as a biomarker for CIU. 

Methods: CIU patients were recruited during doctor’s visit for treatment. Four groups of 3 patients each were selected: Active hive with positive chronic urticaria (CU) Index results; Active hive with negative CU Index; Positive CU Index but no active hives; and Negative CU Index with no active hives.  MicroRNAs were isolated from plasma and analyzed using miR microarray technology to determine the amount of each of the 2567 known human miRs.

Results: Those transcripts which show statistically significant differences between groups (p value <0.01), including those that have low signals but show greater than two-fold differences, are listed.  MiR-2355-3p, 2355-5P, 29c-5P and 4264 are of particular interest because they are uniquely expressed in patients with active hives and with positive CU index.  We also compared patients with active hives to those without hives, and found 12 miRs (3691-3p, 6799-3p, 3180, 3187-3p, 6769a-5p, 6800-3p, 1184, 205-5p, 4733-5p, 1910-5p, 4649-5p, 302c) which are differentially expressed.

Conclusions: We have identified 16 miRs which are differentially expressed in CIU. Further study is needed to confirm these findings and to investigate the source genes from which they originate and the potential target genes on which they might act.