Histamine H4 receptor expression is elevated in human nasal polyp tissue

Abstract

Altered histamine metabolism is thought to be involved in the pathomechanism of nasal polyposis characterized by local eosinophil infiltration. The present study was performed to determine whether histamine receptors play a role in the effect of histamine in nasal polyp tissue. The findings suggest that the expression of H1 and H4 receptors is elevated in polyp tissue (p = 0.045; p < 0.001), while the level of H2 and H3 receptors is not increased significantly. The elevation of H1 and H4 receptors' expression may indicate that the histamine related mechanisms are preferentially mediated through H1 and H4 histamine receptors in the polyp tissue. Simultaneously with increased H4 receptor expression, the concentration of eosinophil cationic protein (ECP) was increased significantly in polyp tissue (p = 0.002). One may speculate that the H4 receptor mediated histamine effects have a role in eosinophil accumulation and activation in inflammatory diseases of the nasal and paranasal sinus mucosa, such as nasal polyposis.

The role of histamine H4 receptor in immune and inflammatory disorders

“…, 2007), a limited number of studies have attempted to identify H 4 receptor alterations in human samples derived from inflamed tissues. For instance, the increased levels of H 4 receptors in normal nasal turbinate mucosa and in nasal polyp tissue and the tendency for correlation between the expression of H 4 receptors and eosinophil cationic protein led to the speculation that the receptor may have a role in mediating histamine effects and eosinophil accumulation and activation in nasal and paranasal sinus mucosa inflammatory diseases (Jókúti et al. , 2007).…”

New antihistamines – perspectives in the treatment of some allergic and inflammatory disorders

“…H4R receptors occur predominantly in the peripheral immune cells, as mast cells, eosinophils, neutrophils, dendritic cells, Langerhans cells, natural killer (NK) cells, monocytes, T cells (including γδT, T helper 1, 2, Th17, and CD8 cells), keratinocytes, inflammatory dendritic epidermal cells, fibroblasts as well as (without any functional data at this stage) epithelial cells and basophils [6, 12]. Expression of H4R in nasal polyp tissue taken from patients with chronic rhinosinusitis is significantly higher than in normal nasal mucosa [62]. One recent study questions the presence of H4R in human monocytes [63].…”

“…JNJ7777120 also decreased IgE concentration and increased IFN-Ƴ level in an allergic rhinitis model in mice and rats [146, 147], including on repeated oral administration [146]. It was shown that administration of H4R antagonists A-940894 and JNJ7777120 inhibited chemotaxis and influx of immune cells, two processes also important in AR [62, 73, 81].…”