Impact of Mycobacterium vaccae immunization on lung histopathology in a murine model of chronic asthma.
BACKGROUND
Therapeutic modalities of asthma have not been proved to be successful in reversing the already established chronic changes of airways.


OBJECTIVE
We aimed to determine the impact of heat-killed Mycobacterium vaccae immunization, a potent Th1 stimulant, on chronic changes of asthma.


METHODS
Newborn BALB/c mice were divided into three groups; mice in M. vaccae group received 107 colony-forming units (CFU)/50 micro L of heat-killed M. vaccae subcutaneously on days 3, 14 and 42 before the development of chronic asthma model, whereas mice in control and chronic asthma groups received saline. Subsequently, mice in M. vaccae and chronic asthma groups were administered 10 micro g/100 micro L of ovalbumin (OVA) on days 43, 45, 47, 49, 51, 53 and 55 intraperitoneally, and 20 micro g/10 micro L of OVA on days 83, 86 and 89 intratracheally. Mice in control group received saline on the same days.


RESULTS
Comparison of M. vaccae and chronic asthma groups showed statistically significant differences in goblet cell numbers, thickness of basement membrane and subepithelial smooth muscle of small, medium and large airways and epithelial thickness of medium airways. There was no significant difference between the control and M. vaccae groups except for goblet cell numbers of medium and large airways, and epithelial thickness of medium airways.


CONCLUSIONS
Results of our study suggested that immunization by M. vaccae of newborn mice would prevent some of the chronic changes of airways due to asthma.
Ozdemir
C
C
Marmara University, School of Medicine, Pediatric Allergy and Immunology Division and Haydarpasa Numune Hospital, Pathology Division, Istanbul, Turkey. cozdemir@superonline.com
Akkoc
T
T
Bahceciler
N N
NN
Kucukercan
D
D
Barlan
I B
IB
Basaran
M M
MM
D000818:Animals; D000831:Animals, Newborn; D001249:Asthma / Q000473:pathology / Q000628:therapy*; D001428:Bacterial Vaccines / Q000627:therapeutic use*; D001485:Basement Membrane / Q000473:pathology; D001706:Biopsy; D001980:Bronchi / Q000473:pathology; D002908:Chronic Disease; D004195:Disease Models, Animal; D020397:Goblet Cells / Q000473:pathology; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C; D009130:Muscle, Smooth / Q000473:pathology; D009161:Mycobacterium / Q000276:immunology*; D015164:Vaccines, Inactivated / Q000627:therapeutic use
D001428:Bacterial Vaccines; D015164:Vaccines, Inactivated