A study issued in “Mediators of Inflammation” revealed that elevated levels of matrix metalloproteinase-12 (MMP-12) and mas-related G protein-coupled receptor-X2 (MRGPRX2) in allergic rhinitis (AR) patients are positively correlated with disease severity. Furthermore, serum MMP-12 demonstrated the potential ability to discriminate people who respond to sublingual immunotherapy (SLIT).

The purpose of this research was to assess the potential of circulating MRGPRX2 and MMP-12 as new biomarkers for assessing disease severity and predicting clinical effectiveness of SLIT in house dust mite-induced AR patients. A total of 110 patients with moderate-to-severe persistent AR (AR group) and 40 healthy controls were included (HC group). MRGPRX2 and MMP-12 circulating levels were assessed, and their relationships with illness severity were investigated.

SLIT was administered to all AR patients, and the effectiveness was assessed. Serum samples were obtained one year and three years following treatment. The relationships between serum MRGPRX2 and MMP-12 levels and clinical effectiveness were investigated. MRGPRX2 and MMP-12 serum concentrations were higher in AR group than in the HC group. Raised MMP-12 levels were linked to total nasal symptom score (TNSS) and visual analog scale (VAS). However, serum MRGPRX2 levels were linked to VAS alone.

Finally, 100 and 80 subjects were categorized as effective or ineffective, after 1-year and 3-year follow-ups, respectively. Lower serum MRGPRX2 and MMP-12 levels were seen in the effective group when compared to ineffective group. Even though serum MRGPRX2 and MMP-12 levels did not alter substantially following one year of SLIT, serum MMP-12 levels were lower three years later when compared to one-year post-SLIT and baseline levels.

According to the receiver operating characteristic (ROC), serum MMP-12 is a promising and useful biomarker for predicting the effectiveness of SLIT. Hence, serum levels of MRGPRX2 and MMP-12 may be used as biological indicators to reflect the severity of AR in patients. SLIT clinical responsiveness might also be reliably predicted by MMP-12 levels in the blood.