Navigation Links
Flu immunity is affected by how many viruses actually cause the infection

Bethesda, MDNot only does the type of flu virus affect a patient's outcome, but a new research report appearing in the Journal of Leukocyte Biology suggests that the number of viruses involved in the initial infection may be important too. Scientists from Canada found that when mice were infected by relatively high concentrations of the flu virus, they not only developed immunity against the virus that infected them, but this also promoted the generation of a type of immune cell in the lungs poised to rapidly react against infections with other strains of the flu, as well. Mice that were infected with a relatively low concentration of the virus developed weaker immunity against the strain that infected them, did not build up this crucial population of immune cells in the lungs, and showed only delayed immunity toward other flu strains. This discovery could pave the way for new prophylactic strategies to fight flu infections and provides a novel basis for vaccine design.

"Hopefully, the findings of our study will help to develop better vaccine preparations that will be more effective in inducing protective cellular immunity to fight against infectious pathogens such as bacteria, viruses and fungi," said Martin V. Richter, Ph.D., the lead researcher involved in the work from the Department of Medicine at the Universit de Sherbrooke and Centre de Recherche Clinique tienne-Le Bel in Qubec, Canada.

To make this discovery, scientists infected two groups of mice with two different infectious doses of influenza A (H3N2) and analyzed several aspects of inflammation and immunity during the initial infection as well as during reinfection with a different strain of virus. The first group was infected with a low dose of the virus whereas the second group was infected with a high dose of the same virus. Mice infected with the high dose showed increased morbidity, a greater degree of lung inflammation, but also a greater recruitment of influenza-specific immune cells (CD8+ T cells) into their lungs, and a better generation of long-lived respiratory CD8+ T cells called memory CD8+ T cells. In contrast, the mice infected with the low dose of virus suffered less from primary infection but all of the immune responses were induced to lower levels. Consequently, reinfection of mice, 60 days after primary infection, revealed that mice previously infected with a higher dose showed increased protection due to greater magnitude of the memory CD8+ T cell pool present in their lungs before reinfection. This is the first demonstration that the initial infectious dose has an important impact on the generation of specific types of immune memory cells and on the degree of immune protection against reinfection.

"Recent experience with emerging and mutating strains of influenza virus highlight how very few changes in this virus could lead to a catastrophic flu crisis," said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology. "While considerable efforts have been invested in predicting new emerging flu strains for our yearly vaccines, it is impossible to prepare for every possible way the flu can mutate. This new research shows that it may be possible to enhance current vaccines to offer broader protection against different flu strains, known and unknown."


Contact: Cody Mooneyhan
Federation of American Societies for Experimental Biology

Related biology news :

1. Gut microbes battle a common set of viruses shared by global populations
2. Brothers in arms: Commensal bacteria help fight viruses
3. IU role in Human Microbiome Project exposes battle history between bacteria, viruses in human body
4. To spread, nervous system viruses sabotage cell, hijack transportation
5. Berkeley Lab scientists generate electricity from viruses
6. BGI, GMU, Mass. Eye and Ear and OUHSC announce agreement to sequence 100 human adenoviruses
7. Gene mutations cause massive brain asymmetry
8. Double the pain: RUB biologists find the cause of pain in the treatment of fair skin cancer
9. Glycogen accumulation in neurons causes brain damage and shortens the lives of flies and mice
10. Yeast cell reaction to Zoloft suggests alternative cause, drug target for depression
11. Changes in brains blood flow could cause brain freeze
Post Your Comments:
(Date:11/16/2015)... 2015  Synaptics Inc. (NASDAQ: SYNA ), ... announced expansion of its TDDI product portfolio with ... and display driver integration (TDDI) solutions designed to ... TDDI products add to the previously-announced TD4300 ... resolution), and TD4322 (FHD resolution) solutions. All four ...
(Date:11/11/2015)... Minn. , Nov. 11, 2015   MedNet Solutions ... entire spectrum of clinical research, is pleased to announce that ... in Clinical Trials (PCT) event, to be held November ... be able to view live demonstrations of iMedNet ... and learn how iMedNet has been able to ...
(Date:11/9/2015)... Nov. 9, 2015  Synaptics Inc. (NASDAQ: SYNA ... announced broader entry into the automotive market with a ... the pace of consumer electronics human interface innovation. Synaptics, ... ideal for the automotive industry and will be implemented ... Europe , Japan , ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... , ... November 24, 2015 , ... The United States ... of the 2016 USGA Green Section Award. Presented annually since 1961, the USGA Green ... or her work with turfgrass. , Clarke, of Iselin, N.J., is an ...
(Date:11/24/2015)... , Nov. 24, 2015 /CNW/ - iCo Therapeutics ... today reported financial results for the quarter ended ... expressed in Canadian dollars and presented under International ... United States ," said Andrew Rae ... advancements regarding iCo-008 are not only value enriching ...
(Date:11/24/2015)... 2015 /PRNewswire/ - Aeterna Zentaris Inc. (NASDAQ:  AEZS) (TSX: AEZ) ... of the Toronto Stock Exchange, confirms that as of ... corporate developments that would cause the recent movements in ... --> About Aeterna Zentaris Inc. ... Aeterna Zentaris is a specialty biopharmaceutical company engaged ...
(Date:11/24/2015)... ... ... This fall, global software solutions leader SAP and AdVenture Capital brought together dozens ... BIG ideas to improve health and wellness in their schools. , Now, the top ... of SAP's Teen Innovator, an all-expenses paid trip to Super Bowl 50, and an ...
Breaking Biology Technology: