Biotin supplementation increases expression of genes encoding interferon-gamma, interleukin-1beta, and 3-methylcrotonyl-CoA carboxylase, and decreases expression of the gene encoding interleukin-4 in human peripheral blood mononuclear cells.

Stimulation of immune cells by antigens triggers changes in the transcription of genes encoding cytokines and other proteins; these changes in gene expression are part of the normal immune response. Previous studies have provided evidence that biotin status may affect secretion of cytokines by immune cells. Here we determined whether biotin supplementation affects gene expression in human immune cells. Peripheral blood mononuclear cells were isolated from healthy adults before and after supplementation with 8.8 micro mol biotin/d for 21 d. Cells were cultured ex vivo with concanavalin A for 21 h to simulate stimulation with antigens. Expression of genes that play roles in cytokine metabolism, cell proliferation, signal transduction, stress response, apoptosis and biotin homeostasis was quantified by using DNA microarrays and reverse transcriptase-polymerase chain reaction. The abundance of mRNA encoding interferon-gamma, interleukin-1beta, and 3-methylcrotonyl-CoA carboxylase was 4.3, 5.6 and 8.9 times greater, respectively, after supplementation with biotin compared with before supplementation. In contrast, the abundance of mRNA encoding interleukin-4 was 6.8 times greater before supplementation than after supplementation. These data suggest that biotin supplementation affects gene expression in human immune cells. Effects of biotin on gene expression are likely to modulate the response of immune cells to antigens.