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Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae
09:12

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The role played by tumor necrosis factor during localized and systemic infection with Streptococcus pneumoniae

Alun C Kirby1, John G Raynes, Paul M Kaye

  • 1Immunology Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom. ak510@york.ac.uk

The Journal of Infectious Diseases
|April 6, 2005
PubMed

Insights

Tumor necrosis factor (TNF) is not essential for initial resistance to Streptococcus pneumoniae infection. However, TNF plays a crucial role in enhancing survival during lethal infections by delaying systemic organ damage.

Area of Science:

  • Immunology
  • Microbiology
  • Infectious Diseases

Background:

  • Tumor necrosis factor (TNF) is implicated in host resistance against Streptococcus pneumoniae infections.
  • Anti-TNF therapies in humans are associated with increased susceptibility to pneumococcal infections.
  • The precise role of TNF in anti-pneumococcal responses requires further investigation.

Observation:

  • Primary resistance and pulmonary inflammatory responses to nonlethal Streptococcus pneumoniae challenge occurred independently of TNF.
  • TNF deficiency led to more rapid death in mice challenged with lethal Streptococcus pneumoniae serotype 3.
  • TNF-deficient mice exhibited extensive liver damage during lethal infection, indicating systemic disease.

Findings:

  • TNF is dispensable for a complete cellular pulmonary inflammatory response to Streptococcus pneumoniae.
  • TNF enhances survival from disseminated lethal infection.
  • TNF delays systemic organ damage, contributing to improved survival outcomes.

Implications:

  • TNF is not required for initial containment of Streptococcus pneumoniae infection in the lungs.
  • Targeting TNF may exacerbate severe pneumococcal disease by impairing systemic defense mechanisms.
  • Understanding TNF's role is critical for managing pneumococcal infections, especially in patients on anti-TNF therapy.

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