|
|
||||||||
Department of Physiology, College of Medicine, National Cheng-Kung University, Tainan, Taiwan, Republic of China
Macrophages from prototypical Th1 strains (e.g., C57BL/6) and Th2 strains (e.g., BALB/c) are classified as M-1 and M-2 phenotypes. We investigated the different phagocytic responses between M-1 and M-2 bronchoalveolar macrophages (BAMs) under resting and two various exercise conditions. At rest, M-1 BAMs showed higher phagocytic capacity of unopsonized particles, higher expression of MARCO (macrophage receptor with collagenous structure), and higher generation of NO than M-2 BAMs. Severe exercise, but not moderate exercise, significantly enhanced both phagocytosis of unopsonized particles and expression of MARCO in M-2 BAMs. In contrast, M-1 BAMs were unaffected by either exercise protocol. The phagocytosis of unopsonized particles was largely mediated by MARCO, especially in M-1 BAMs. Secreted products from cultured M-2 BAMs isolated after severe exercise, but not those from M-1 BAMs, enhanced BAM phagocytosis. The cultured M-1 BAMs secreted phagocytosis inhibitors, and this effect could be blocked by NO antagonists. Moreover, the extent of phagocytosis suppression induced by M-1 BAM-secreted products correlated with their production of nitrite/nitrate. Exogenous NO donors as well as NO derivatives, nitrite and nitrate, suppressed the BAM phagocytosis. We propose that while the severe exercise-enhanced phagocytosis in M-2 BAMs was largely mediated by MARCO up-regulation and secretion of stimulators, the lack of exercise effect in M-1 BAMs could be partially due to the constitutive secretion of NO-related suppressors. In conclusion, genetically different mice use different strategies in regulating BAM activity under resting conditions and in response to various exercise paradigms.
This article has been cited by other articles:
![]() |
E. A. Szliter, S. Lighvani, R. P. Barrett, and L. D. Hazlett Vasoactive Intestinal Peptide Balances Pro- and Anti-Inflammatory Cytokines in the Pseudomonas aeruginosa-Infected Cornea and Protects against Corneal Perforation J. Immunol., January 15, 2007; 178(2): 1105 - 1114. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. F. Hamilton Jr., S. A. Thakur, J. K. Mayfair, and A. Holian MARCO Mediates Silica Uptake and Toxicity in Alveolar Macrophages from C57BL/6 Mice J. Biol. Chem., November 10, 2006; 281(45): 34218 - 34226. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. H. Rosenblum Lichtenstein, R. M. Molina, T. C. Donaghey, and J. D. Brain Strain Differences Influence Murine Pulmonary Responses to Stachybotrys chartarum Am. J. Respir. Cell Mol. Biol., October 1, 2006; 35(4): 415 - 423. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. J. G. de Almeida, L. B. Chiarini, J. P. da Silva, P. M. R. e Silva, M. A. Martins, and R. Linden The cellular prion protein modulates phagocytosis and inflammatory response J. Leukoc. Biol., February 1, 2005; 77(2): 238 - 246. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.A. Preston, K.W. Beagley, P.G. Gibson, and P.M. Hansbro Genetic background affects susceptibility in nonfatal pneumococcal bronchopneumonia Eur. Respir. J., February 1, 2004; 23(2): 224 - 231. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Granucci, F. Petralia, M. Urbano, S. Citterio, F. Di Tota, L. Santambrogio, and P. Ricciardi-Castagnoli The scavenger receptor MARCO mediates cytoskeleton rearrangements in dendritic cells and microglia Blood, October 15, 2003; 102(8): 2940 - 2947. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |