Exploring Rana dybowskii HSP90's Role in Antigen Cross-Presentation During Aeromonas hydrophilaInfection

Antigen cross-presentation enables antigen-presenting cells (APCs) to internalize and process exogenous antigens, subsequently presenting the derived peptides to CD8+ T lymphocytes via class I major histocompatibility complex (MHC-I) molecules. This sophisticated immunological process not only integrates innate and adaptive immune responses but also enhances antimicrobial defenses, offering critical insights for developing anti-infective therapies while maintaining immune homeostasis. Although heat shock protein 90 (HSP90) is recognized as a pivotal regulator in this pathway, the specific isoforms involved (e.g., HSP90αvs. HSP90β) and their mechanistic contributions remain poorly defined.To dissect HSP90's functional specificity, an Aeromonas hydrophila-infected Rana dybowskii model was established. A multimodal analytical framework integrating transcriptomics, quantitative real-time PCR (qRT-PCR), and immunoblotting was implemented to (1) characterize the expression dynamics of HSP90 isoforms (HSP90AA1/αand HSP90AB1/β), and (2) quantify their protein abundance profiles. Furthermore, spatial transcriptomic mapping was performed to evaluate mRNA levels of key cross-presentation components—including HSP70, antigen processing transporters (TAP1/2), TAP-associated protein (TAPBP), and MHC-I—across four immunological compartments: hepatic, splenic, dermal, and muscular tissues.For the first time, transcriptome data was presented according to the liver of Rana dybowskii, theHSP90AA1, HSP90AB1, and HSP70genes were cloned, and it demonstrated that the skin is the most sensitive immune organ in amphibian species, while the liver plays a pivotal role in regulating the inflammatory response. TAP1was identified as a core gene in the antigen cross-presentation pathway, and HSP90AA1as a key gene responsive to changes within the organismin the present study. Furthermore, the findings underscore the functional significance of understanding the binding interactions between HSP90AA1 and HSP70 in the antigen cross-presentation pathway. Deciphering this complex process may provide additional insights for immunotherapy, and the development of related inhibitors, ultimately aiding in the design of effective treatment strategies for patients.