Immunohistochemical investigation of transient receptor potential melastatin-2 and spexin immunoreactivity in atopic dermatitis and mycosis fungoides

Background

Atopic dermatitis (AD) is a chronic, pruritic, and inflammatory dermatosis seen in individuals with an atopic predisposition. This study aimed to examine the immunoreactivity of spexin and TRPM2 in skin samples from patients with AD and MF lesions using immunohistochemical methods.

Materials and methods

The study utilized a total of 60 skin samples, comprising 20 from AD patients, 20 from MF patients, and 20 from control subjects. Skin samples from patients diagnosed with other dermatological diseases, malignancies, and diabetes mellitus were excluded from the study. During staining, the prevalence (0.1: <25%, 0.4: 26–50%, 0.6: 51–75%, 0.9: 76–100%) and intensity (0: none, + 0.5: very low, + 1: low, + 2: moderate, + 3: intense) of immunoreactivity were used as criteria to establish a histo-score. Calculations employed the formula histo-score = prevalence x intensity.

Results

Statistically significant higher spexin histoscores were observed in both the AD and MF patient groups compared to the control group (1.30 ± 0.46, 1.04 ± 0.29, and 0.20 ± 0.07, respectively; p = 0.000). Similarly, TRPM2 histoscores were significantly higher in the AD and MF patient groups compared to the control group (1.12 ± 0.28, 1.02 ± 0.30, and 0.20 ± 0.07, respectively; p = 0.000).

Conclusion

It is hypothesized that the increase in the neuropeptide spexin in both AD and MF is triggered by inflammation and contributes to itching mechanisms via galanin receptors. TRPM2, an ion channel, is speculated to be a marker of Reactive Oxygen Species (ROS) in chronic inflammatory dermatoses like AD, but it may not serve as a potential biomarker for distinguishing chronic inflammatory dermatoses from MF.