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09:01
An In vitro Model to Study Immune Responses of Human Peripheral Blood Mononuclear Cells to Human Respiratory Syncytial Virus Infection
Published on: December 10, 2013
Host defense in respiratory infections
1Department of Medicine, Section of Pulmonary and Critical Care Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA. dwelsh@lsuhsc.edu
The Medical Clinics of North America
|October 30, 2001
Summary
The respiratory system has multiple layers of defense against pathogens, starting with physical barriers and progressing to immune cells. Understanding these lung defenses highlights the complexity of maintaining respiratory health.
Area of Science:
- Immunology
- Pulmonology
- Microbiology
Background:
- The respiratory tract possesses intricate defense mechanisms to prevent and combat infections.
- These defenses include physical barriers, clearance systems, and cellular immunity.
Purpose of the Study:
- To elucidate the multifaceted nature of respiratory tract defenses against pathogenic organisms.
- To emphasize the sequential activation of innate and adaptive immune responses in the lungs.
Main Methods:
- Review of established knowledge on respiratory defense mechanisms.
- Analysis of clinical defects in host defense to illustrate component importance.
Main Results:
- Respiratory defenses comprise mechanical barriers, mucociliary clearance, cough reflexes, and phagocytic cells like alveolar macrophages.
- Specific immune responses are initiated only when innate defenses fail.
Conclusions:
- The respiratory system relies on a complex, multi-layered defense strategy involving both physical and immunological components.
- Clinical examination of host defense failures underscores the critical role of each element in lung immunity.
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