Genetic, morphological and functional characteristics of human tryptase

Introduction. Tryptase, a mast cell-derived protease, plays a significant role in the diagnosis and pathogenesis of allergic and inflammatory diseases. The baseline serum tryptase level is used as a biomarker for the diagnosis of conditions associated with mast cell activation, which may be accompanied by severe allergic reactions and anaphylaxis. Studying tryptase isoforms, along with their structural and functional variations, aids in understanding genetic predisposition and the mechanisms underlying inflammatory diseases such as bronchial asthma and chronic inflammation.

Materials and Methods. A detailed investigation of the structure and function of various tryptase isoforms was conducted. Biochemical properties human tryptase isoforms were examined. The analysis included the study of the genes TPSAB1, TPSB2, TPSG1, and TPSD1, which encode different forms of tryptase, and the assessment of their activity. Tryptase secretion has been investigated, along with various factors influencing its release.

Results. Tryptase, a mast cell-derived enzyme, is represented by four major isoforms—_α, _β, _γ, and _δ. Among the secreted isoforms, α- and _β-tryptases are the most prominent, _β-tryptase exhibits the highest catalytic activity, whereas _α-tryptase demonstrates limited enzymatic function. The tryptase genes are located on chromosome 16 and show a high degree of homology. Key genes TPSAB1 and TPSB2 encode active forms of tryptase, and an increased number of TPSAB1 copies leads to elevated baseline tryptase levels, heightening the risk of allergic reactions. Tryptase plays a role in inflammatory and allergic processes, including mast cell degranulation, affecting vascular permeability and leukocyte recruitment.

Conclusion. The collected data on the secretion and functions of tryptase produced by mast cells suggest that it can be regarded as a multifunctional mediator, acting through specific molecular and cellular mechanisms. Tryptase is critically involved in the pathogenesis of inflammatory processes and allergic responses across multiple organs and systems, including the respiratory tract and the skin. Understanding the biochemical characteristics and genetic features of tryptase isoforms opens new opportunities for the development of diagnostic and therapeutic approaches for high-impact allergic diseases.

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