Biology subjects

Lamendella, R.

Publications and source records attributed to Lamendella, R..

4 recordsLinked to original sources

bioRxiv2021

Plasma microbiome in COVID-19 subjects: an indicator of gut barrier defects and dysbiosis

The gut is a well-established route of infection and target for viral damage by SARS-CoV-2. This is supported by the clinical observation that about half of COVID-19 patients exhibit gastrointestinal (GI) symptoms. We asked whether the analysis of plasma could provide insight into gut barrier dysfunction in patients with COVID-19 infection. Plasma samples of COVID-19 patients (n=30) and healthy control (n=16) were collected during hospitalization. Plasma microbiome was analyzed using 16S rRNA sequencing, metatranscriptomic analysis, and gut permeability markers including FABP-2, PGN and LPS in both patient cohorts. Almost 65% (9 out 14) COVID-19 patients showed abnormal presence of gut microbes in their bloodstream. Plasma samples contained predominately Proteobacteria, Firmicutes, and Actinobacteria. The abundance of gram-negative bacteria (Acinetobacter, Nitrospirillum, Cupriavidus, Pseudomonas, Aquabacterium, Burkholderia, Caballeronia, Parabhurkholderia, Bravibacterium, and Sphingomonas) was higher than the gram-positive bacteria (Staphylococcus and Lactobacillus) in COVID-19 subjects. The levels of plasma gut permeability markers FABP2 (1282{+/-}199.6 vs 838.1{+/-}91.33; p=0.0757), PGN (34.64{+/-}3.178 vs 17.53{+/-}2.12; p<0.0001), and LPS (405.5{+/-}48.37 vs 249.6{+/-}17.06; p=0.0049) were higher in COVID-19 patients compared to healthy subjects. These findings support that the intestine may represent a source for bacteremia and may contribute to worsening COVID-19 outcomes. Therapies targeting the gut and prevention of gut barrier defects may represent a strategy to improve outcomes in COVID-19 patients.

microbiology↗

bioRxiv2020

Variation in the Gut Microbiota of Common Marmosets: Differences with Colony of Origin and Integration

Characterization of the gut microbiome may aid understanding and management of natural and experimental disease states in research animals, thereby promoting reproducibility. In this study, the rectal bacterial communities of three separate common marmoset (Callithrix jacchus) breeding colonies were defined using 16S rRNA sequencing of rectal swab samples. Study animals originated from two German colonies and a United States colony (JHU). The two German cohorts, previously fed the same diet, were imported into the JHU facility; they were then isolated, transitioned onto JHU diet, and then moved into rooms housing JHU animals. To dissect the contributions of diet and integration in shaping the rectal bacterial community, samples were collected from German origin marmosets upon JHU arrival (baseline), following diet transition (100 d), and following cohousing (390 d). Baseline and 390 d samples were collected from stably maintained JHU marmosets. Bacterial community composition was distinct between all three cohorts at baseline, suggesting that factors other than primary diet confer significant differences between captive populations. Beta-diversity of the animals from the two German colonies converged by 100 d but remained distinct from JHU sample beta-diversity throughout the 390-d study, indicating that diet had greater influence on bacterial community composition than did housing animals within the same room. Our results demonstrate substantial differences in gut bacteria between different captive marmoset colonies, with persistence of these differences following husbandry standardization and housing integration. Goals of rigor and reproducibility in research underscore the need to consider microbial differences between marmosets of diverse origin. ImportanceCharacterizing gut microbial populations is expected to promote health and enhance research reproducibility in animal studies. As use of common marmosets as animal models of human diseases expands, evaluating the marmoset gut bacterial community will be critical for interpreting research findings, especially as marmosets are prone to gastrointestinal inflammation. In this study, using 16S rRNA sequencing of rectal swab samples, we compared bacterial community among three captive colonies of marmosets at baseline and following importation of cohorts from two of the colonies into the third colony. Diet history had sustained influence on bacterial community composition, while housing the animals within the same room over a period of eight months did not appear to be a major factor. These persistent differences in marmoset gut bacterial community highlight the need for careful consideration of animal origin as a variable in marmoset research studies.

microbiology↗

bioRxiv2019

Formula alters preterm infant gut microbiota and increases its antibiotic resistance load

Infants are at a high risk of acquiring infections caused by antibiotic resistant bacterial strains. Antibiotic resistance gene (ARG) load is typically higher in newborns than in adults, but it is unknown which factors besides antibiotic treatment affect the load. Our study demonstrates that inclusion of any formula in the newborn diet causes shifts in microbial community composition that result in higher ARG loads in formula-fed infants compared to infants not fed formula. The effect of formula was especially strong in premature newborns and newborns treated with antibiotics. Interestingly, antibiotics alone without formula did not have a detectable impact on the ARG load of the newborn gut. We also observed that formula-fed infants had enriched numbers of pathogenic species and were depleted in typical infant gut species such as Bifidobacterium bifidum. The results suggest infant feeding choices should include assessment of risks associated with elevated ARG abundance.

microbiology↗

bioRxiv2019

Bacterial Hyperswarming as a Protective Response to Intestinal Stress

Bacterial swarming, a collective movement on a surface, has rarely been associated with human pathophysiology. Here, we report for the first time that bacterial swarmers are associated with protection against intestinal inflammation. We show that bacterial swarmers are highly predictive of intestinal stress in mice and humans. We isolated a novel Enterobacter swarming strain, SM3, from mouse feces. SM3 and other known commensal swarmers contrast to their respective swarming-deficient, but swimming-competent isogenic strains abrogated intestinal inflammation in mice. Treatment of colitic mice with SM3, but not its mutants, enriched beneficial fecal anaerobes belonging to the family, Bacteroidales S24-7. We observed SM3 swarming associated pathways in the in vivo fecal metatranscriptomes. In vitro growth of S24-7 was enriched in presence of SM3 or its mutants conjecturing that bacterial swarming in vivo might influence SM3s access to S24-7 in the intestines. Overall, our work identifies a new paradigm in which intestinal stress allows for the emergence of swarming bacteria, which can counterintuitively heal intestinal inflammation.

microbiology↗