- Disease Modeling
- Infectious Diseases
Dr. Eric Lafontaine’s research group is interested in, and has contributed to, the fields of bacterial pathogenesis and host-pathogen interactions for the organisms Moraxella catarrhalis, Burkholderia mallei, and Burkholderia pseudomallei. Moraxella catarrhalis is a human-specific bacterium and causative agent of otitis media in children, sinusitis, and respiratory infections in adult patients with chronic obstructive pulmonary disease. Little is known about pathogenesis by M. catarrhalis and there is currently no vaccine for the organism. Burkholderia mallei, the causative agent of the highly contagious zoonotic disease glanders, is endemic to many parts of the world and is considered a re-emerging biosafety and biosecurity threat. Melioidosis, which is caused by Burkholderia pseudomallei, is recognized as a global emerging tropical disease. The U. S. Federal Select Agent Program also classifies these Burkholderia species as Tier 1 agents (highest risk level) and no vaccine exists to reduce the risk of the life-threatening infections they cause. Dr. Lafontaine’s group has developed and validated 4 animal models, namely a chinchilla model of nasopharyngeal colonization to study M. catarrhalis, a mouse model of aerosol infection to study B. pseudomallei and B. mallei, an experimental model of equine glanders to study B. mallei, and a marmoset intranasal model of infection to studyB. mallei. These models are being used to study pathogenesis by the organisms, examine the role of surface antigens in virulence, and develop medical countermeasures.
Adherence factors from Moraxella catarrhalis, Burkholderia mallei and B. pseudomallei
- BSc (1991) Medical Biology, Universite du Quebec a Trois Rivieres
- PhD (1997) Microbiology and Infectious Diseases, University of Calgary
Dr. Lafontaine’s research program consists of identifying and characterizing surface antigens that are expressed by the gram negative bacteria Moraxella catarrhalis, Burkholderia pseudomallei, and Burkholderia mallei, with emphasis on molecules functioning as adherence factors. Our lab’s hypothesis is that these molecules, or fragments thereof, are potential vaccine antigens. Furthermore, adherence is an important step in pathogenesis by most infectious agents and we believe that studying this process will shed some light on the means by which the organisms cause disease. M. catarrhalis is a major causative agent of otitis media, sinusitis, as well as respiratory infections in patients with chronic obstructive pulmonary disease. Very little is known about pathogenesis by M. catarrhalis and there is currently no vaccine for this bacterium. B. pseudomallei causes melioidosis whereas B. mallei causes glanders. These two closely related bacteria are potential bioterrorism agents and there is an urgent need to understand their biology as well as develop vaccines. Once identified, adhesins are tested for their vaccinogenic potential (e.g., Do antibodies to these molecules bind to the surface of bacteria, block adherence, and/or have bactericidal activity? Is immunization with the adhesins protective in animal models?).
- Verhaegh SJ, Stol K, de Vogel CP, Riesbeck K, Lafontaine ER, Murphy TF, van Belkum A, Hermans PW, Hays JP. Comparative analysis of the humoral immune response to Moraxella catarrhalis and Streptococcus pneumoniae surface antigens in children suffering from recurrent acute otitis media and chronic otitis media with effusion. Clin Vaccine Immunol. 2012 Jun;19(6):914-8.
- Verhaegh SJ, de Vogel CP, Riesbeck K, Lafontaine ER, Murphy TF, Verbrugh HA, Jaddoe VW, Hofman A, Moll HA, van Belkum A, Hays JP. Temporal development of the humoral immune response to surface antigens of Moraxella catarrhalis in young infants. Vaccine. 2011 Aug 5;29(34):5603-10.
- Balder R, Lipski S, Lazarus JJ, Grose W, Wooten RM, Hogan RJ, Woods DE, Lafontaine ER. Identification of Burkholderia mallei and Burkholderia pseudomallei adhesins for human respiratory epithelial cells. BMC Microbiol. 2010 Sep 28;10:250.
- Balder R, Krunkosky TM, Nguyen CQ, Feezel L, Lafontaine ER. Hag mediates adherence of Moraxella catarrhalis to ciliated human airway cells. Infect Immun. 2009 Oct;77(10):4597-608.
- LaFontaine ER, Snipes LE, Bullard B, Brauer AL, Sethi S, Murphy TF. Identification of domains of the Hag/MID surface protein recognized by systemic and mucosal antibodies in adults with chronic obstructive pulmonary disease following clearance of Moraxella catarrhalis. Clin Vaccine Immunol. 2009 May;16(5):653-9.
- Balder R, Lafontaine ER. Laboratory Maintenance of Moraxella catarrhalis. Curr Protoc Microbiol. 2008 Nov;Chapter 6:Unit 6B.1.
- Bullard B, Lipski S, Lafontaine ER. Regions important for the adhesin activity of Moraxella catarrhalis Hag. BMC Microbiol. 2007 Jul 3;7:65.
- Akimana C, Lafontaine ER. The Moraxella catarrhalis outer membrane protein CD contains two distinct domains specifying adherence to human lung cells. FEMS Microbiol Lett. 2007 Jun;271(1):12-9. Epub 2007 Mar 28.
- Balder R, Hassel J, Lipski S, Lafontaine ER. Moraxella catarrhalis strain O35E expresses two filamentous hemagglutinin-like proteins that mediate adherence to human epithelial cells. Infect Immun. 2007 Jun;75(6):2765-75. Epub 2007 Mar 19.