TY  - JOUR
A1  - Alzheimer, Mona
A1  - Svensson, Sarah L.
A1  - König, Fabian
A1  - Schweinlin, Matthias
A1  - Metzger, Marco
A1  - Walles, Heike
A1  - Sharma, Cynthia M.
T1  - A three-dimensional intestinal tissue model reveals factors and small regulatory RNAs important for colonization with Campylobacter jejuni
JF  - PLoS Pathogens
N2  - The Gram-negative Epsilonproteobacterium Campylobacter jejuni is currently the most prevalent bacterial foodborne pathogen. Like for many other human pathogens, infection studies with C. jejuni mainly employ artificial animal or cell culture models that can be limited in their ability to reflect the in-vivo environment within the human host. Here, we report the development and application of a human three-dimensional (3D) infection model based on tissue engineering to study host-pathogen interactions. Our intestinal 3D tissue model is built on a decellularized extracellular matrix scaffold, which is reseeded with human Caco-2 cells. Dynamic culture conditions enable the formation of a polarized mucosal epithelial barrier reminiscent of the 3D microarchitecture of the human small intestine. Infection with C. jejuni demonstrates that the 3D tissue model can reveal isolate-dependent colonization and barrier disruption phenotypes accompanied by perturbed localization of cell-cell junctions. Pathogenesis-related phenotypes of C. jejuni mutant strains in the 3D model deviated from those obtained with 2D-monolayers, but recapitulated phenotypes previously observed in animal models. Moreover, we demonstrate the involvement of a small regulatory RNA pair, CJnc180/190, during infections and observe different phenotypes of CJnc180/190 mutant strains in 2D vs. 3D infection models. Hereby, the CJnc190 sRNA exerts its pathogenic influence, at least in part, via repression of PtmG, which is involved in flagellin modification. Our results suggest that the Caco-2 cell-based 3D tissue model is a valuable and biologically relevant tool between in-vitro and in-vivo infection models to study virulence of C. jejuni and other gastrointestinal pathogens.
KW  - in vitro
KW  - stem cells
KW  - invasion
KW  - host
KW  - adhesion
KW  - epithelial cells
KW  - translocation
KW  - virulence
KW  - responses
KW  - microenvironment
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-229454
VL  - 16
IS  - 2
ER  - 
TY  - JOUR
A1  - Masic, Anita
A1  - Hurdayal, Ramona
A1  - Nieuwenhuizen, Natalie E.
A1  - Brombacher, Frank
A1  - Moll, Heidrun
T1  - Dendritic Cell-Mediated Vaccination Relies on Interleukin-4 Receptor Signaling to Avoid Tissue Damage after Leishmania major Infection of BALB/c Mice
JF  - PLoS Neglected Tropical Diseases
N2  - Prevention of tissue damages at the site of Leishmania major inoculation can be achieved if the BALB/c mice are systemically given L. major antigen (LmAg)-loaded bone marrow-derived dendritic cells (DC) that had been exposed to CpG-containing oligodeoxynucleotides (CpG ODN). As previous studies allowed establishing that interleukin-4 (IL-4) is involved in the redirection of the immune response towards a type 1 profile, we were interested in further exploring the role of IL-4. Thus, wild-type (wt) BALB/c mice or DC-specific IL-4 receptor \(\alpha\) (IL-4R \(\alpha\))-deficient (CD11c\(^{cre}\)IL-4R \(\alpha^{-/lox}\) BALB/c mice were given either wt or IL-4R \(\alpha\)-deficient LmAg-loaded bone marrow-derived DC exposed or not to CpG ODN prior to inoculation of 2x10\(^5\) stationary-phase L. major promastigotes into the BALB/c footpad. The results provide evidence that IL4/IL-4R alpha-mediated signaling in the vaccinating DC is required to prevent tissue damage at the site of L. major inoculation, as properly conditioned wt DC but not IL-4R alpha-deficient DC were able to confer resistance. Furthermore, uncontrolled L. major population size expansion was observed in the footpad and the footpad draining lymph nodes of CD11c\(^{cre}\)IL-4R \(\alpha^{-/lox}\) mice immunized with CpG ODN-exposed LmAg-loaded IL-4R \(\alpha\)-deficient DC, indicating the influence of IL-4R \(\alpha\)-mediated signaling in host DC to control parasite replication. In addition, no footpad damage occurred in BALB/c mice that were systemically immunized with LmAg-loaded wt DC doubly exposed to CpG ODN and recombinant IL-4. We discuss these findings and suggest that the IL4/IL4R \(\alpha\) signaling pathway could be a key pathway to trigger when designing vaccines aimed to prevent damaging processes in tissues hosting intracellular microorganisms.
KW  - cytokines
KW  - necrosis-factor-alpha
KW  - T helper cell
KW  - visceral leishmaniasis
KW  - intracellular pathogen
KW  - interferon-gamma
KW  - IL-12 production
KW  - deficient mice
KW  - resistance
KW  - responses
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133869
VL  - 6
IS  - 7
ER  -