Pathogenic microorganisms, including bacteria and viruses that are capable of causing diseases, represent a major global challenge to human health and welfare. Increasing numbers of multi-drug resistant bacterial strains, along with newly emerging diseases, have resulted in a surge in need for the development of effective therapeutics to target pathogens. Furthermore, the ability of pathogens to adapt to and suppress the host’s innate immune response presents a challenge requiring novel approaches to disrupting pathogen virulence. Pathogens utilize specific and complex networks of molecular machinery in order to survive and propagate within their host organism. The mechanisms at the interface of host-pathogen interactions remain largely unresolved. Ultimately, understanding these pathogenic mechanisms is crucial for developing effective therapeutics.

Mass spectrometry-based techniques continue to advance our understanding of the intricate relationship between host and pathogen. These applications can be used to investigate both host and pathogen cells and includehigh-resolution data dependent or targeted proteomic analysis, coverage of complex proteomes via high through-put methods and data processing, as well as elemental and metabolomic analyses. Although these techniques have provided a great deal of insight, further improvements are necessary to continue to advance our understanding of this field. Coordination of information generated from multi-‘omics’ approaches, in conjunction with genomic and transcriptomic techniques, will help to resolve the mechanisms underlying host-pathogen interactions, leading to discoveries that aid in combating disease. The goal of this collection is to showcase current mass spectrometry-based methods employed to resolve the molecular mechanisms underlying host-pathogen interactions.