[Preliminary investigation into the allergic rhinitis complicated with acute bacterial sinusitis in mice].
OBJECTIVE
To develop a mouse model of bacterial rhinosinusitis superposed on allergic rhinitis (AR), and to explore whether ongoing allergic rhinitis enhance the acute sinus infection and inflammation associated with Streptococcus pneumoniae (SP).


METHODS
Fourty mice of C57BL6/J were randomly divided on average into 4 groups: A [ovalbumin (OVA) + SP], B [OVA + normal saline (NS)], C [phosphate buffered solution (PBS) + SP] and D (PBS + NS). (1) Group A and B were sensitized by intraperitoneal injection with 200 microl (10%) OVA on days 1 through 9, and exposed to OVA (6%) intranasally on days 10 through 17, to induce allergic inflammation. OVA was replaced with PBS in group C and D in the same way. (2) Subsequently, group A and C were inoculated with SP intranasally on day 13, and NS was used in group B and D. On the 6th day after inoculation, mice were killed. Blood was collected from the orbital venous sinus after anesthesia. The heads were embedded with paraffin and serial sections were followed and stained with hematoxylin-eosin and toluidine blue (0.5%) for histological analysis and inflammation cells count. The number of polymorphonuclear neutrophils (PMN) and eosinophils (EOS) per square millimeter of sinus mucosa were calculated by using a computer-aided special software under microscope.


RESULTS
AR models were successfully established in 9 mice from group A and 8 from group B. Histologic examination of the sinus from group A and B revealed significant mucosal edema and dilated venules. The symptoms were mild in group C, and no symptom was observed in group D. PMN (x +/- s) in group A (139.3 +/- 26.5)/mm2 was significantly higher than that in group B (70.7 +/- 16.7)/mm2, C (63.0 +/- 14.7)/mm2 and D (40.2 +/- 14.1)/mm2 respectively (P < 0.01); EOS and serous IL-5 level in group A (134.6 +/- 25.5)/mm2, (48.2 +/- 13.9) pg/ml and B (116.2 +/- 25.2)/mm2, (40.8 +/- 7.8) pg/ml, were higher than that in group C (16.7 +/- 2.7)/mm2, (23.9 +/- 8.7) pg/ml (P < 0.05) and D (13.4 +/- 4.9)/mm2, (24.6 +/- 6.5) pg/ml (P < 0.05).


CONCLUSIONS
The data demonstrate that an ongoing local allergic response augments bacterial infection in mice, and allergic sensitization alone without SP does not induce the sinus infection.
An
Yun-Fang
YF
Department of Otorhinolaryngology, Second Hospital of Shanxi Medical University, Taiyuan 030001, China.
Wang
Wei-Hua
WH
Zhao
Chang-Qing
CQ
Xue
Jin-Mei
JM
Zhao
Hai-Liang
HL
D000818:Animals; D004195:Disease Models, Animal; D004804:Eosinophils / Q000276:immunology; D015848:Interleukin-5 / Q000097:blood / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000276:immunology; D011008:Pneumococcal Infections; D012221:Rhinitis, Allergic, Perennial / Q000382:microbiology*; D012852:Sinusitis / Q000382:microbiology*
D015848:Interleukin-5