Serpinb3a, also related to the squamous cell carcinoma antigen (SCCA) family, is a serine-protease inhibitor. It is involved in multiple signal transduction pathways, and plays important roles in regulating proteolysis, with the ability to inhibit both serine and cysteine proteinases [5,6]. It participates in biological processes such as lysosomal necrosis cell death pathway, which overlaps with radiation-induced apoptosis [2].

In gene-knockout mouse models, Serpinb3a-/-mice showed radioresistance, with increased longevity in long-term bone marrow cultures, and radioresistant hematopoietic and stromal cell lines [2]. In asthma models, Serpinb3a-null mice had attenuated airway hyperresponsiveness, goblet cell hyperplasia, and mucus production [3]. In atopic dermatitis models, Serpinb3a-null mice had attenuated barrier dysfunction and early inflammatory response following allergen exposure [4]. In tumor studies, intratumoral knockdown of Serpinb3a in mouse models led to tumor growth inhibition, reduced immunosuppressive cell infiltration, enhanced cytotoxic T-cell function, and sensitized tumors to radiotherapy [1].

In conclusion, Serpinb3a plays significant roles in various physiological and pathological processes. Studies using Serpinb3a-deficient mouse models have revealed its importance in radiation response, asthma, atopic dermatitis, and tumor immunity. Understanding Serpinb3a's functions provides potential therapeutic targets for treating related diseases.