Our bodies are made out of trillions of cells – and harbor the same number of microbes. These microbes have numerous functions, from providing us with nutrients and shaping our immune system to preventing pathogens from colonizing.
We study bacteria and fungi that live in the gut and their role during infection with the human pathogen Salmonella enterica serovar Typhimurium. This bacterium infects 1.5 million people each year in the USA alone. Infection results in self-limiting inflammatory diarrhea in healthy people, but can lead to bacteremia and death in people with a compromised immune system.
We use in vitro models and small animal models to study how bacteria and fungi interact with each other, Salmonella, and the host. Next to conventionally raised animals we use animals that are devoid of any microbes (germ-free). These animals can be selectively colonized with bacteria and fungi of interest. This allows us to understand relationships of these microbes and their interactions with the host in a less complex system.
Behnsen J*, Narang P*, Hasenberg M, Gunzer F, Bilitewski U, Klippel N, Rohde M, Brock M, Brakhage AA, Gunzer M. Environmental dimensionality controls the interaction of phago-cytes with the pathogenic fungi Aspergillus fumigatus and Candida albicans. PLoS Pathog. 2007 Feb 2;3(2):e13 *contributed equally Cover image of this issue of PLoS Pathogens
Behnsen J, Hartmann A, Schmaler J, Gehrke A, Brakhage AA, Zipfel PF. The opportunistic human pathogenic fungus Aspergillus fumigatus evades the host complement system. Infect Immun. 2008 Feb;76(2):820-7
Behnsen J, Lessing F, Schindler S, Wartenberg D, Jacobsen ID, Thoen M, Zipfel PF, Brakhage AA. Secreted Aspergillus fumigatus protease Alp1 degrades human complement proteins C3, C4, and C5. Infect Immun. 2010 Aug;78(8):3585-94 Editor’s Spotlight Article of this issue of Infection and Immunity.
Behnsen J, Jellbauer S, Wong CP, Edwards RA, George MD, Ouyang W, Raffatellu M. The Cytokine IL-22 Promotes Pathogen Colonization by Suppressing Related Commensal Bacteria. Immunity. 2014 Feb 20;40(2):262-73.
Selected for Immunity press release and as “Featured Free Article”. Discussed in the article preview “The battle in the gut”, Immunity 2014, and in an article in “The Scientist”.
Jellbauer S, Perez Lopez A, Behnsen J, Gao N, Nguyen T, Murphy C, Edwards RA, and Raffatellu M. Beneficial Effects of Sodium Phenylbutyrate Administration During Infection with Salmonella enterica serovar Typhimurium. Infect Immun 2016 Aug 19;84(9):2639-52.
Diaz-Ochoa VE, Lee CS, Liu JZ, Klaus SM, Behnsen J, Rathi SG, Mastroianni JR, Edwards RA, Jacobo CM, Cerasi M, Battistoni A, Ouellette AJ, Chazin WJ, Skaar EP, Raffatellu M. Salmonella Typhimurium overcomes calprotectin-dependent and independent mechanisms of manganese sequestration via specialized transporters. Cell Host Microbe. 2016 Jun 8;19(6):814-25
Li S, Vinci A, Behnsen J, Cheng C, Jellbauer S, Raffatellu M, Sousa KM, Edwards R, Nguyen NT, Stamos MJ, Pigazzi A. Bariatric Surgery Attenuates DSS-Induced Colitis in an Obese Murine Model. Surg Obes Relat Dis Apr;13(4):661-668
Review articles and previews
Brakhage AA, Bruns S, Thywissen A, Zipfel PF, Behnsen J. Interaction of phagocytes with filamentous fungi. Curr Opin Microbiol. 2010 Aug;13(4):409-15
Hasenberg M, Behnsen J, Krappmann S, Brakhage A, Gunzer M. Phagocyte responses towards Aspergillus fumigatus. Int J Med Microbiol. 2011 Jun;301(5):436-44
Behnsen J, Deriu E, Sassone-Corsi M, Raffatellu M. Rational design of probiotics. Cold Spring Harb Perspect Med. 2013 Mar 1;3(3)
Behnsen J, Raffatellu M. Keeping the peace: aryl hydrocarbon receptor signaling modulates the mucosal microbiota. Immunity. 2013 Aug 22;39(2):206-7
Behnsen J, Perez-Lopez A, Nuccio SP, Raffatellu M. Exploiting host immunity: the Salmonella paradigm. Trends Immunol. 2015 Feb;36(2):112-20
Perez-Lopez A, Behnsen J, Nuccio SP, Raffatellu M. Immunity to pathogenic intestinal bacteria. Nat Rev Immunol. 2016 Mar;16(3):135-48
Behnsen J, Raffatellu M. Siderophores: more than stealing iron. MBio 2016 Nov 15;7(6).
Behnsen J. Protectors of the Neonatal Gut: Clostridia Send Pathogens Packing. Cell Host Microbe 2017 Jun 14;21(6):651-652