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Published on: February 23, 2014
Immunological roles of Pasteurella multocida toxin (PMT) using a PMT mutant strain
Tae Jung Kim1, Nguyen Tat Toan, Eun Jin Jang
1Biotheraphy Human Resources Center, Chonnam National University, Gwangju 500-757, Republic of Korea.
Abstract:
The immunological role of the Pasteurella multocida toxin (PMT) in mice was examined using a PMT mutant strain. After a nasal inoculation, the mutant strain failed to induce interstitial pneumonia. Moreover, PMT had no significant effect on the populations of CD4+, CD8+, CD3+, and CD19+ immunocytes in blood or on the populations of CD4+ and CD8+ splenocytes (P<0.01). However, there was a significant increase in the total number of cells in the BAL samples obtained from the wild-type P. multocida-inoculated mice. On the other hand, the level of IL-1 expression decreased when the macrophages from the bronchio-alveolar lavage were stimulated with PMT. Overall, PMT appears to play some role (stimulating and/or inhibiting) in the immunological responses but further studies will be required to confirm this.
Insights
The Pasteurella multocida toxin (PMT) plays a complex role in mouse immunity. While not causing pneumonia, PMT influences immune cell counts and IL-1 expression in bronchoalveolar lavage fluid.
Area of Science:
- Immunology
- Microbiology
- Veterinary Science
Background:
- Pasteurella multocida toxin (PMT) is a key virulence factor.
- The specific immunological functions of PMT require further elucidation.
Purpose of the Study:
- To investigate the immunological role of PMT in a mouse model.
- To assess the impact of PMT on pneumonia induction and immune cell populations.
Main Methods:
- Nasal inoculation of mice with wild-type and PMT mutant Pasteurella multocida strains.
- Analysis of interstitial pneumonia, blood immunocyte populations (CD4+, CD8+, CD3+, CD19+), splenocyte populations (CD4+, CD8+), and bronchoalveolar lavage (BAL) cell counts.
- Assessment of IL-1 expression in BAL macrophages stimulated with PMT.
Main Results:
- The PMT mutant strain did not induce interstitial pneumonia.
- PMT did not significantly alter blood immunocyte or splenocyte populations.
- A significant increase in BAL cells was observed in wild-type inoculated mice.
- PMT stimulation decreased IL-1 expression in BAL macrophages.
Conclusions:
- PMT exhibits a multifaceted role in modulating host immunological responses.
- PMT influences cellularity in the lungs and cytokine expression.
- Further research is necessary to fully characterize the stimulatory and inhibitory immunological functions of PMT.
