Strain-dependent activation of the mouse immune response is correlated with Porphyromonas gingivalis-induced experimental periodontitis.
OBJECTIVE
To evaluate the effect of oral infection with three Porphyromonas gingivalis strains on alveolar bone loss (ABL) and its correlation with the mouse immune response.


METHODS
Mice were orally infected with P. gingivalis strains 381, 33277 and 53977. After 42 days, maxillae were analysed for ABL using micro-computed tomography and the serum for anti-P.gingivalis IgG1 and IgG2a levels. The cytokine response to P. gingivalis was tested using the subcutaneous chamber model.


RESULTS
The P. gingivalis 53977-infected group showed the highest ABL, which was significantly different from all other groups (p<0.001). In addition, the humoral response to P. gingivalis 53977 was significantly lower than the response to P. gingivalis 381 and 33277 (p< or =0.01). The IgG2a/IgG1 ratio was higher in the P. gingivalis 33277-infected group (1.6) compared with the P. gingivalis 381-infected group (0.51). Four days post-infection, interleukin (IL)-1beta levels remained significantly higher in the P. gingivalis 53977-infected group only (1198.2+/-260.0, p<0.05), while IL-4 levels remained significantly higher in the P. gingivalis 381-infected group (265.8+/-131.6, p<0.05).


CONCLUSIONS
The high levels of ABL induced by P. gingivalis 53977 were inversely correlated with the humoral response to this bacterium. In addition, ABL was correlated with an elevated pro-inflammatory response.
Wilensky
Asaf
A
Department of Periodontology, School of Dental Medicine, Hadassah and the Hebrew University Medical Center, PO Box 12272, Jerusalem 91120, Israel. asafw@ekmd.huji.ac.il
Polak
David
D
Awawdi
Suhair
S
Halabi
Amal
A
Shapira
Lior
L
Houri-Haddad
Yael
Y
D016301:Alveolar Bone Loss / Q000276:immunology / Q000382:microbiology; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D016866:Bacteroidaceae Infections / Q000276:immunology*; D005260:Female; D056724:Immunity, Humoral / Q000276:immunology; D007074:Immunoglobulin G / Q000097:blood; D053583:Interleukin-1beta / Q000032:analysis; D015847:Interleukin-4 / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D009055:Mouth / Q000382:microbiology; D010518:Periodontitis / Q000276:immunology / Q000382:microbiology*; D016966:Porphyromonas gingivalis / Q000145:classification / Q000276:immunology*; D055114:X-Ray Microtomography
D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D053583:Interleukin-1beta; D015847:Interleukin-4