Clostridium difficile Research and Development Community – September 2014


Here is the latest from the                              Clostridium difficile research community:

The role of host factors especially those involved in the intestinal inflammatory response and pathogenesis of against Clostridium difficile is not well understood. Trindade et all looked at the role of leukotrienes in modulating host susceptibility to CDI in C57BL/6 mice. Leukotrienes are proinflammatory lipid mediators which are not involved in the pathogenesis of CDI.


Scientists from Dr. Rupnik’s group in Slovenia describe the sequence diversity of 16S-23S rRNA intergenic spacer region of 43 C difficile strains representing different PCR ribotypes. Her groups suggests that homologous recombination as a possible mechanism responsible for the evolution of 16S-23S rRNA intergenic spacer region. Diversity in sequence length, the presence or absence of different sequence modules; tRNAAla genes and different combinations of spacers of different lengths (33 bp, 53 bp or 20 bp) and 9 bp direct repeats separating the spacers could be used to describe 22 different structural groups.


The use of the bacterial second messenger cyclic di-GMP (c-di-GMP) as an adjuvant to stimulate inflammation by initiating innate immune cell recruitment and triggering the release of pro-inflammatory cytokines and chemokines was studied in the context of a C.difficile toxin expressed from an adenovirus vaccine. Although co-expression of the cyclic di-GMP via an Ad5 vector expressing diguanylate cyclase lead to modest imcrease in T cell responses, antibody titers were not boosted.


Lipotechoic acids (LTA) are novel targets for vaccination against C.difficile. LTA is expressed on spores as well as vegetative cells. In this study, the authors report on the isolation fo 5 LTAs from C. difficile as a microheterogenous mixture, differing in size and composition, structure–activity relationship studies impossible. The authors describe the synthesis of these LTAs and their functions.;jsessionid=9C01075014FEF3357A300E57738049EA.f02t04


The microbiome of the infant gut is established very early following birth. In this study the authors report on the resistome of the infant gut consists of aminoglycoside and β-lactam resistance reservoir even in the absence of pathogens that could provide the needed evolutionary pressure. The resistome of the infant gut is also established very early in the life of the infant, probably at birth.


Chandrabali Ghose-Paul,MS,PhD, Chairperson of Research and Development