Diet-Induced Obesity Dramatically Reduces the Efficacy of a 2009 Pandemic H1N1 Vaccine in a Mouse Model

[tetano]

J Infect Dis. 2011 Dec 5. [Epub ahead of print]
Diet-Induced Obesity Dramatically Reduces the Efficacy of a 2009 Pandemic H1N1 Vaccine in a Mouse Model.
Kim YH, Kim JK, Kim DJ, Nam JH, Shim SM, Choi YK, Lee CH, Poo H.
Source

Animal Model Center, and.
Abstract

Background. Obesity, a risk factor for increased severity of diverse diseases, is believed to have negative impact on vaccine efficacy. Recently, mortality has emerged as an outcome of pandemic influenza A virus subtype H1N1, necessitating development of effective vaccine strategies. Here we investigated effects of diet-induced obesity on vaccine-induced immune responses and protective efficacy against pandemic H1N1 influenza virus.Methods. Diet-induced obese and lean C57BL/6J mice were immunized with commercial monovalent 2009 H1N1 vaccine, and antigen-specific antibody responses and neutralizing activities were observed. Following vaccination, mice were challenged with homologous H1N1 virus, and pathogenesis and mortality were examined.Results. Vaccine-induced H1N1-specific antibody responses and neutralizing activities were markedly reduced in obese mice. Consistent with antibody responses, lung virus titers were significantly higher in obese mice than in lean controls after challenge. In addition, obese group showed greatly increased expression of proinflammatory cytokines and chemokines in lung tissue, severe lung inflammation, and higher eventual mortality rate (100%) compared with that among lean control mice (14%).Conclusions. Our results show that prophylactic immune responses and protectiveness induced by 2009 H1N1 vaccine could be extremely compromised in diet-induced obesity. These results suggest that novel vaccination strategies for high-risk groups, including the obese population, are required.

PMID:
22147801
[PubMed - as supplied by publisher]

http://www.ncbi.nlm.nih.gov/pubmed/22147801

[tetano]

Re: Diet-Induced Obesity Dramatically Reduces the Efficacy of a 2009 Pandemic H1N1 Vaccine in a Mouse Model

J Infect Dis. (2012) 205 (2): 172-173. doi: 10.1093/infdis/jir740 First published online: December 5, 2011


Influenza and Obesity: Will Vaccines and Antivirals Protect?


Correspondence: Melinda A. Beck, PhD, Department of Nutrition, University of North Carolina at Chapel Hill, 2303 MHRC, CB # 7461UNC, Chapel Hill, NC 27599-7461 (melinda_beck@unc.edu).

(See the article by Kim et al, on pages 244?51, and the article by O?Brien et al, on pages 252?61.)

There is a worldwide pandemic of obesity. The World Health Organization estimates 500 million adults and almost 43 million children under the age of 5 years to be obese (body mass index >30) [1]. According to the Centers for Disease Control and Prevention, nearly one-third of the adult US population is obese. Obesity has been definitively linked to a wide range of comorbidities, including increased coronary heart disease, type 2 diabetes, hypertension, and dyslipidemia [2]. Beyond the contribution of obesity to these chronic diseases, surprisingly little attention has been given to the effects of obesity on the immune response to infectious diseases.

Several studies have now reported that obesity was associated with a poor outcome following infection with 2009 pandemic influenza (pH1N1) [3?7]. Kwong and colleagues reported that obese individuals, in addition to being at risk from pH1N1, were also at greater risk for hospitalization from seasonal influenza infection [8]. In sum, these reports demonstrate that obesity increases the risks associated with influenza infection.

Beyond these clinical studies on the role of obesity in influenza infection, 2 studies in this issue of the Journal using a mouse model and pH1N1 infections provide new insights into obesity?s effect on the immune response to influenza virus infection and the ability of vaccination or antiviral treatment to mitigate the effects of infection.

Vaccination remains our ?

http://jid.oxfordjournals.org/content/205/2/172.extract