Animal Models to Understand Host–Pathogen Interactions

Abstract

Infectious diseases are the outcome of molecular cross-communication between host and its pathogens. During the molecular cross talks, host–pathogen proteomics, genomics, and immunological responses are highly influenced. Host would respond to their pathogen through several mechanisms for the clearance of pathogens. It is always necessary to identify the underlying molecular mechanisms of pathogenicity. In general, host–pathogen cross talks are complex and dynamic in nature that exploits most of the host cell functions. Immune responses are initiated by host cell as a response to the pathogen attack. It was found to be very difficult, exclusive, and ethically inappropriate to evaluate the notorious pathogen interactions that cause adverse effects on human health at the organism level. Hence, the need for experimental animal models to understand host–pathogen interactions always emerges. Incorporation of a host animal model not only allows the identification of host–pathogen interactions but also lights into the phenotypic impacts and molecular mechanisms of pathogenicity. In ancient times, better understanding of virulence determinants and antimicrobial therapy has been hindered by the restrictions of adequate experimental models and necessary tools to measure the severity of infections. Laboratory hosts that have been employed as an alternative for mammal infection models are Caenorhabditis elegans, amoeba, Drosophila melanogaster, and Danio rerio. These models are used as infection models owing to their shorter generation times, flexibility, and affordability to study forward and reverse genetic analysis. Even though humans are excellent model to study human pathogens, their use in studies is limited due to the safety, ethical, and expense concerns. Among other primates, monkey, baboons, and chimpanzees are idyllic and mimic most of the infectious diseases. But rodents such as mice, rats, rabbits, hamsters, and guinea pigs are widely proposed model hosts due the limited application of other primate models. Here, we review the available animal models to study host–pathogen interactions with a focus to decipher pathogenicity mechanisms.