It is crucial to consider the importance of the microbiome and the gut–lung axis in the context of SARS-CoV-2 infection. This pilot study examined the fecal microbial composition of patients with COVID-19 following a 3-month recovery. Using for the first time metagenomic analysis based on all hypervariable regions (V1-V9) of the 16S rRNA gene, we have identified 561 microbial species; however, 17 were specific only for the COVID-19 group (n = 8). The patients’ cohorts revealed significantly greater alpha diversity of the gut microbiota compared to healthy controls (n = 14). This finding has been demonstrated by operational taxonomic units (OTUs) richness (p < 0.001) and Chao1 index (p < 0.01). The abundance of the phylum Verrucomicrobia was 30 times higher in COVID-19 patients compared to healthy subjects. Accordingly, this disproportion was also noted at other taxonomic levels: in the class Verrucomicrobiae, the family Verrucomicrobiaceae, and the genus Akkermansia. Elevated pathobionts such as Escherichia coli, Bilophila wadsworthia, and Parabacteroides distasonis were found in COVID-19 patients. Considering the gut microbiota’s ability to disturb the immune response, our findings suggest the importance of the enteric microbiota in the course of SARS-CoV-2 infection. This pilot study shows that the composition of the microbial community may not be fully restored in individuals with SARS-CoV-2 following a 3-month recovery.

The effectiveness of thiopurine drugs in inflammatory bowel disease (IBD) was confirmed more than a half-century ago. It was proven that these can be essential immunomodulatory medications. Since then, they have been used routinely to maintain remission of Crohn’s disease (CD) and ulcerative colitis (UC). The cytotoxic properties of thiopurines and the numerous adverse effects of the treatment are controversial. However, the research subject of their pharmacology, therapy monitoring, and the search for predictive markers are still very relevant. In this article, we provide an overview of the current knowledge and findings in the field of thiopurines in IBD, focusing on the aspect of their cytotoxicity. Due to thiopurines’ benefits in IBD therapy, it is expected that they will still constitute an essential part of the CD and UC treatment algorithm. More studies are still required on the modulation of the action of thiopurines in combination therapy and their interaction with the gut microbiota.

Inflammatory bowel disease (IBD) is an incurable, chronic disorder of the gastrointestinal tract whose incidence increases every year. Scientific research constantly delivers new information about the disease and its multivariate, complex etiology. Nevertheless, full discovery and understanding of the complete mechanism of IBD pathogenesis still pose a significant challenge to today’s science. Recent studies have unanimously confirmed the association of gut microbial dysbiosis with IBD and its contribution to the regulation of the inflammatory process. It transpires that the altered composition of pathogenic and commensal bacteria is not only characteristic of disturbed intestinal homeostasis in IBD, but also of viruses, parasites, and fungi, which are active in the intestine. The crucial function of the microbial metabolome in the human body is altered, which causes a wide range of effects on the host, thus providing a basis for the disease. On the other hand, human genomic and functional research has revealed more loci that play an essential role in gut homeostasis regulation, the immune response, and intestinal epithelial function. This review aims to organize and summarize the currently available knowledge concerning the role and interaction of crucial factors associated with IBD pathogenesis, notably, host genetic composition, intestinal microbiota and metabolome, and immune regulation.

Paleogenetics has significantly changed since its inception almost forty years ago. Initially, molecular techniques available to the researchers offered minimal possibilities for ancient DNA analysis. The subsequent expansion of the scientific tool cabinet allowed for more remarkable achievements, combined has with the newfound popularity of this budding field of science. Finally, a breakthrough was made with the development of next-generation sequencing (NGS) technologies and the update of DNA isolation protocols, through which even very fragmented aDNA samples could be used to sequence whole genomes. In this paper, we review the achievements made thus far and compare the methodologies utilized in this field of science, discussing their benefits and challenges.

Background: The main aim of this study was to evaluate whether selected polymorphic variants in genes from the inflammatory pathway can be predictors of pulmonary or digestive manifestation of cystic fibrosis, as well as of severity of lung disease. Materials and methods: Using pyrosequencing and sequencing we have genotyped 12 variants in TNF (rs361525, rs1800629), CXCL8 (rs4073, rs2227306, rs2227307, rs188378669), IL1B (rs16944, rs1143634, rs1142639, rs1143627), IL6 (rs1800795) and IL10 (rs1800896) genes in a cohort of 55 Polish patients with diagnosed cystic fibrosis and controls. In our study group, a pulmonary manifestation of disease revealed 44 of subjects (80%), and digestive symptoms dominated in 11 (20%) of analyzed individuals. Severe lung dysfunction has occurred in 20 (36.4%) of patients. Results: We proved, that two promoter variants of IL1B, rs1143627 (c.-118G > A) and rs16944 (c.-598T > C) are presented significantly more often in patients with severe character of lung disease compared to mild (82.5% vs. 62.8%, p-value 0.030, and 87.5% vs. 64.3%, p-value 0.008, respectively) in cystic fibrosis course. Haplotype AC formed by both changes had also a higher frequency (80%) in patients with severe course compared to the mild character (61.4%) of disease. However, the frequency of promoter variant TNF c.-308C > T (rs1800629) was presented at a significantly lower level in the patient’s group compared to healthy controls (2.7% vs. 15%, p-value 0.001). Furthermore, the presence of methicillin-resistant Staphylococcus aureus significantly correlated with the lower FEV1% in patients (p-value 0.01). Conclusions: Genetic variants, rs1143627 and rs16944, of IL1B are promising candidates as predictors of the severe character of lung disease in Polish patients with cystic fibrosis.

Inflammatory bowel disease (IBD) is an incurable, chronic disorder of the gastrointestinal tract, whose incidence increases every year. Scientific research is constantly delivering new information about the disease and its multivariate, complex etiology. Nevertheless, full discovery and understanding of the complete mechanism of IBD pathogenesis still pose a significant challenge to today's science. Recent studies unanimously confirmed the association of gut microbial dysbiosis with IBD, as well as its contribution to the regulation of the inflammatory process. It transpires that not only the altered composition of pathogenic and commensal bacteria is characteristic of disturbed intestinal homeostasis in IBD, but also of viruses, parasites, and fungi, which are active in the intestine. In fact, the crucial function of microbial metabolome in the human body is altered, which causes a wide range of effects in the host, thus providing a basis for the disease. On the other hand, human genomic and functional research revealed more loci that play an essential role in gut homeostasis regulation, immune response, and intestinal epithelial function. This review aims to organize and summarize currently available knowledge concerning the role and interaction of crucial factors associated with IBD pathogenesis, particularly host genetic composition, intestinal microbiota, and metabolome, with immune regulation.