Distinct ability to accumulate eosinophils during the inflammatory cellular response to M. bovis BCG in the mouse pleural cavity.
OBJECTIVE
The host response to Mycobacteria focuses on the development of cell-mediated immunity and granuloma formation. Here, we investigated the onset of cellular responses to mycobacteria in murine pleurisy.


METHODS
Distinct mouse strains previously described as Bcg susceptible or resistant were inoculated intrathoracically with different doses of live M. bovis BCG.


METHODS
At various time intervals, cells harvested from the inflammatory site were identified and ultra-structurally analysed.


RESULTS
BCG-induced pleurisy had two peaks of cellular influx at 1 and 15 days after infection. At the first half hour, macrophages were found to be heavily infected. Neutrophil arrival started after 2 h of infection and peaked at 4 h. At this time, neutrophils were found ingesting mycobacteria exclusively with a high infecting dose. BCG was potently more eosinophilotactic in Bcg susceptible mice than in the resistant ones and to other well known eosinophilia inducers: IL-5, PAF-acether or LPS.


CONCLUSIONS
Mycobacterial load and mouse susceptibility seem to determine the early granulocyte dynamics in the lesion.
Werneck-Barroso
E
E
Institute of Thorax Diseases, Federal University of Rio de Janeiro, Brazil.
Moura
A C
AC
Monteiro
M M
MM
Menezes de Lima Júnior
O
O
de Meirelles
M N
MN
Henriques
M G
MG
D000276:Adjuvants, Immunologic; D000818:Animals; D001500:BCG Vaccine / Q000276:immunology / Q000633:toxicity*; D004804:Eosinophils / Q000473:pathology*; D005122:Exudates and Transudates / Q000166:cytology; D007958:Leukocyte Count; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008854:Microscopy, Electron; D009504:Neutrophils / Q000276:immunology; D010994:Pleura / Q000473:pathology*; D010998:Pleurisy / Q000139:chemically induced / Q000473:pathology*; D013045:Species Specificity; D013997:Time Factors
D000276:Adjuvants, Immunologic; D001500:BCG Vaccine