The biomedical potential of tardigrade proteins: A review

Tardigrades are ubiquitous microinvertebrates exhibiting extreme tolerance to various environmental stressors like low and high temperatures, lack of water, or high radiation. Although exact pathways behind the tardigrade extremotolerance are yet to be elucidated, some molecules involved have been identified. Their evidenced properties may lead to novel opportunities in biomedical and pharmacological development. This review aims to present the general characteristics of tardigrade intrinsically disordered proteins (TDPs: Dsup, CAHS, SAHS, MAHS) and late embryogenesis-abundant proteins (LEA) and provide an updated overview of their features and relevance for potential use in biomedicine and pharmacology. The Dsup reveals a promising action in attenuating oxidative stress, DNA damage, and pyrimidine dimerization, as well as increasing radiotolerance in transfected human cells. Whether Dsup can perform these functions when delivered externally is yet to be understood by in vivo preclinical testing. In turn, CAHS and SAHS demonstrate properties that could benefit the preservation of pharmaceuticals (e.g., vaccines) and biomaterials (e.g., cells). Selected CAHS proteins can also serve as inspiration for designing novel anti-apoptotic agents. The LEA proteins also reveal promising properties to preserve desiccated biomaterials and can act as anti-osmotic agents. In summary, tardigrade molecules reveal several potential biomedical applications advocating further research and development. The challenge of extracting larger amounts of these molecules can be solved with genetic engineering and synthetic biology tools. With new species identified each year and ongoing studies on their extremotolerance, progress in the medical use of tardigrade proteins is expected shortly.