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Published on: February 23, 2014
Pattern changes of mucin gene expression with pneumococcal otitis media.
Y Tsuboi1, Y Kim, M M Paparella
1Otitis Media Research Center, Department of Otolaryngology, School of Medicine, University of Minnesota, 2001 Sixth Street S.E., Rm. 216, Minneapolis, MN 55455, USA. tsubo001@tc.umn.edu
International Journal of Pediatric Otorhinolaryngology
|September 29, 2001
Summary
Pneumococcal ear infections activate specific mucin genes (Muc1-Muc5) in the middle ear, potentially increasing mucin production. This study investigated mucin gene expression changes during Streptococcus pneumoniae infections in rats.
Area of Science:
- Otorhinolaryngology
- Molecular Biology
- Microbiology
Background:
- Mucins are crucial for mucociliary transport in the middle ear and Eustachian tube.
- Inflammatory conditions can alter mucin expression, but specific gene changes during middle ear inflammation are not well understood.
Purpose of the Study:
- To investigate mucin gene expression profiles in rat middle ears and Eustachian tubes following Streptococcus pneumoniae infection.
- To identify specific mucin genes that are up-regulated or activated during pneumococcal otitis media.
Main Methods:
- Rats were inoculated with Streptococcus pneumoniae type 6A.
- Middle ear and Eustachian tube tissues were analyzed for mucin gene expression using reverse transcription polymerase chain reaction (RT-PCR) at various time points post-infection.
- Phosphate-buffered saline (PBS) inoculated rats served as controls.
Main Results:
- Mucin gene Muc2 was expressed in the middle ear mucosa of control rats.
- Following pneumococcal inoculation, Muc1, Muc2, Muc3, Muc4, and Muc5 mucin genes were expressed in the middle ear mucosa in a time-dependent manner.
- In the Eustachian tube, Muc2, Muc4, and Muc5 mucin genes were expressed in both control and infected groups.
Conclusions:
- Pneumococcal infection activated Muc1, Muc3, Muc4, and Muc5 mucin genes in the middle ear mucosa.
- This activation may contribute to the hyper-production of mucin observed in acute pneumococcal otitis media.
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