Host tissue proteins

Host tissue proteins refers to the entire complement of proteins produced by a host organism's cells and tissues. In a therapeutic context, this term is typically used in two ways: as the collective targets for host-directed therapies (HDT) or as contaminants in the manufacturing of recombinant proteins [1]. Host-directed therapies aim to treat infections or other diseases by modulating host pathways—such as the immune response or metabolic processes—rather than targeting the pathogen directly [2]. This approach can help overcome antimicrobial resistance by focusing on stable host components. In bioprocessing, host cell proteins (HCPs) are considered process-related impurities that must be rigorously monitored and removed to ensure drug safety and prevent adverse immunogenic responses [3]. Residual HCPs in a final drug product can act as adjuvants or cause direct allergic reactions in patients. Because the term encompasses thousands of distinct molecular entities with diverse functions, it is classified as a broad category rather than a specific, actionable therapeutic target [4]. [1] Kaufmann, S. H. E., et al. (2018). Nature Reviews Drug Discovery. [2] Zumla, A., et al. (2016). The Lancet Infectious Diseases. [3] Wang, X., et al. (2009). Biotechnology and Bioengineering. [4] Santos, R., et al. (2017). Nature Reviews Drug Discovery.

Other names

Host cell proteinsEndogenous proteinsHost proteomeHost-derived proteins

Modulation of host cellular pathways, including enzyme inhibition, receptor antagonism, or immune system regulation, to treat disease or enhance pathogen clearance [1][2].