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Intracellular Pathogens: Infection, Immunity, and Intervention
Anna Martens-Koop1, Aneesh Thakur2
1Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, SK, Canada.
Abstract:
Intracellular pathogens comprise a diverse group of pathogens that all share a required location in a host cell to infect, survive, and replicate. Intracellular location allows pathogens to hide from host immune responses, avoid competition with other pathogens, mediate host cellular functions, replicate safely, and cause infection that is difficult to target with therapeutics. All intracellular pathogens have varying routes of infiltration into host cells and different host cell preferences. For example, bacteria Mycobacterium tuberculosis chooses to invade antigen-presenting cells, which allows them to moderate host antigen presentation to memory cells, whereas rabies virus prefers to invade neurons because they have pre-existing innate immunity protection systems. Regardless of the pathway that each intracellular pathogen follows, all share the capacity to cause disease if they succeed in entering host cells. Here, we give an overview of selected intracellular pathogens and infections they cause, immune responses they induce, and intervention strategies used to treat and control them.
Insights
Intracellular pathogens infect host cells, evading immune responses and causing difficult-to-treat diseases. This overview covers pathogen types, infections, immune reactions, and control strategies.
Area of Science:
- Microbiology
- Immunology
- Pathogenesis
Background:
- Intracellular pathogens reside within host cells for survival and replication.
- This intracellular niche provides protection from host immune responses and therapeutic interventions.
- Pathogens exhibit diverse invasion strategies and host cell tropisms.
Purpose of the Study:
- To provide an overview of selected intracellular pathogens.
- To describe the infections caused by these pathogens.
- To summarize the immune responses and intervention strategies.
Main Methods:
- Literature review of intracellular pathogens.
- Analysis of pathogen invasion mechanisms.
- Summary of host-pathogen interactions and immune evasion.
Main Results:
- Intracellular pathogens utilize varied routes to enter host cells.
- Specific examples include Mycobacterium tuberculosis and rabies virus with distinct cellular targets.
- Successful invasion leads to disease, necessitating targeted interventions.
Conclusions:
- Understanding intracellular pathogen strategies is crucial for effective treatment.
- Diverse immune responses are elicited, requiring tailored intervention approaches.
- Control strategies must address the unique challenges posed by intracellular infections.
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