Composition of Intestinal Microbiota in Immune-Deficient Mice Kept in Three Different Housing Conditions

Abstract

BackgroundAbundance of commensals constituting the intestinal microbiota (IM) affects the immune system and predisposes to a variety of diseases, including intestinal infections, cancer, inflammatory and metabolic disorders. Housing conditions determine the IM and can hence influence the immune system. We analyzed how both variables affect the IM of four immune-compromized mouse lines kept under different housing conditions.Methodology/Principal FindingsWe investigated the IM composition in mice by quantitative 16S rRNA RT-PCR analysis of the main fecal bacterial groups (Enterobacteriaceae, enterococci, lactobacilli, bifidobacteria, Bacteroides/Prevotella (BP) spp., Clostridium leptum and coccoides groups). Mice were homozygous (HO) or heterozygous (HE) for a targeted inactivating mutation of either the IFN-γ Receptor (R), IFN-γ, Rag1 or IL-4 genes. Overall, differences in IM composition were subtle. However, in the SPF-barrier, total eubacterial loads were higher in Rag1 HE versus Rag1 HO mice as well as in IFN-γR HE versus IFN-γR HO and WT animals. Although absent in WT mice, bifidobacterial loads were higher in HO and HE IFN-γ and Rag1 as well as IL-4 HO mice. Furthermore, BP was slightly lower in HO and HE IFN-γR and IFN-γ mice as well as in IL-4 HO mice as compared to WT controls. Interestingly, IM compositions were comparable in WT mice when kept in individual ventilated cages (IVC) or open cages (OC). IFN-γ HO and HE mice, however, had higher enterobacteria and BP loads, but lacked bifidobacteria when kept in OC versus IVC, as was the case in HO and HE Rag1 mice. In addition, Rag1 HO mice harbored higher clostridial loads when housed in OC as compared to IVC. Unexpectedly, lactobacilli levels were higher in IFN-γR mice when kept in OC versus IVC.Conclusion/SignificanceHousing-dependent and immune-deficiency mediated changes in intestinal microbiota composition were rather subtle but may nevertheless impact immunopathology in experimental models.

Gut Microbiota-Induced Immunoglobulin G Controls Systemic Infection by Symbiotic Bacteria and Pathogens

“…However, compared to WT mice, J H −/− mice exhibited increased numbers of aerobic and anaerobic bacteria in the blood (Figure 3C), spleen, and liver (Figure S2C), as well as increased mortality, which was reduced by administration of broad-spectrum antibiotics prior to and during DSS treatment (Figure 3D). Previous studies have reported conflicting results on the role of IgA in the regulation of the gut microbiota (Suzuki et al, 2004; Thoene-Reineke et al, 2014; Wei et al, 2011). However, we did not observe perturbed gut microbiota in J H −/− mice after 4 weeks of co-housing with WT mice prior to DSS treatment (Figure S2D).…”

Microbiota composition and immune responses during Campylobacter jejuni infection in conventionally colonized IL-10−/− mice lacking nucleotide oligomerization domain 2

“…To address this, fecal samples from uninfected IL-10 –/– mice lacking NOD2 and from IL-10 –/– controls were subjected to 16S rRNA analysis of the most prevalent commensal intestinal groups by quantitative RT-PCR [32, 33]. Notably, the microbiota composition did not differ between naive mice of either genotype as indicated by virtually comparable eubacterial total loads and comparable gene numbers of aerobic, anaerobic, and microaerophilic bacterial groups and species in fecal samples derived from uninfected NOD2 –/– IL-10 –/– and IL-10 –/– mice (Fig.…”

Maternal Antibiotic Treatment Impacts Development of the Neonatal Intestinal Microbiome and Antiviral Immunity

“…Previous studies demonstrated that mice of identical strains housed in different facilities are distinguished by their GIT microbiota and that alterations can occur following transfer from one facility to another (50,51). During the course of our experiments, we initially bred mice in an SPHF facility (standard SPF and Helicobacter pylori-free conditions) where additional strict attention to maintenance of sterile conditions is emphasized.…”