Differential expression of immune-related genes between healthy volunteers and type 2 diabetic patients with spleen-deficiency pattern.

Objective: To investigate the clinical differentia tion of spleen-deficiency pattern (SDP), a group of symptoms and signs defined in terms of Traditional Chinese Medicine for its clinical practice.

Methods: Peripheral venous blood (> 3 mL) was collected from each of six type 2 diabetes mellitus (T2DM)-SDP patients and six healthy volunteers. After the isolation of peripheral white blood cells (PWBCs), total RNA was extracted, and quality control was performed on all RNA samples. Microarray experiments were conducted using the Agilent human whole genome gene chip, and genes demonstrating differential expression were screened. Bioinformatics analysis was conducted on these genes using several online databases.

Results: We screened a total of 175 differentially expressed genes (DEGs), of which 111 (63%) were down-regulated and 64 (37%) were up-regulated in T2DM-SDP patients compared with healthy controls. Among the 175 genes, 158 had biological function annotations: 46 (29%) were directly related to an individual's immune regulation or response, 25 (16%) were associated with substance and energy metabolism of PWBCs which could also indirectly influence immunity, and the remaining 87 (55%) were involved in a variety of PWBC biological processes that might eventually influence the immune function. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis revealed that the DEGs were predominantly enriched in seven immune-related pathways. Hierarchical cluster analysis identified gene expression patterns that were distinguishable between the two study groups.

Conclusion: Our results suggest that T2DM-SDP patients experience significant hypoimmunity and/or immune dysfunctions, and possess a specific gene expression profile. These findings offer new insights into SDP and the clinical pattern differentiation of T2DM-SDP.