Modulation of microRNome by Human Cytomegalovirus and Human Herpesvirus 6 Infection in Human Dermal Fibroblasts: Possible Significance in the Induction of Fibrosis in Systemic Sclerosis

Human cytomegalovirus (HCMV) and Human herpesvirus 6 (HHV-6) have been reportedly suggested as triggers of the onset and/or progression of systemic sclerosis (SSc), a severe autoimmune disorder characterized by multi-organ fibrosis. The etiology and pathogenesis of SSc are still largely unknown but virological and immunological observations support a role for these beta-herpesviruses, and we recently observed a direct impact of HCMV and HHV-6 infection on the expression of cell factors associated with fibrosis at the cell level. Since miRNA expression has been found profoundly deregulated at the tissue level, here we aimed to investigate the impact on cell microRNome (miRNome) of HCMV and HHV-6 infection in in vitro infected primary human dermal fibroblasts, which represent one of the main SSc target cells. The analysis, performed by Taqman arrays detecting and quantifying 754 microRNAs (miRNAs), showed that both herpesviruses significantly modulated miRNA expression in infected cells, with evident early and late effects and deep modulation (>10 fold) of >40 miRNAs at each time post infection, including those previously recognized for their key function in fibrosis. The correlation between these in vitro results with in vivo observations is strongly suggestive of a role of HCMV and/or HHV-6 in the multistep pathogenesis of fibrosis in SSc and in the induction of fibrosis-signaling pathways finally leading to tissue fibrosis. The identification of specific miRNAs may open the way to their use as biomarkers for SSc diagnosis, assessment of disease progression and possible antifibrotic therapies

Characterization of Clostridioides difficile Strains from an Outbreak Using MALDI-TOF Mass Spectrometry

The epidemiology of Clostridioides difficile infection (CDI) has changed over the last two decades, due to the emergence of C. difficile strains with clinical relevance and responsible for nosocomial outbreaks with severe outcomes. This study reports an outbreak occurred in a Long-term Care Unit from February to March 2022 and tracked by using a Matrix-Assisted Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) typing approach (T-MALDI); subsequently, a characterization of the toxigenic and antimicrobial susceptibility profiles of the C. difficile isolates was performed. A total of 143 faecal samples belonging to 112 patients was evaluated and C. difficile DNA was detected in 51 samples (46 patients). Twenty-nine C. difficile isolates were obtained, and three different clusters were revealed by T-MALDI. The most representative cluster accounted 22 strains and was considered to be epidemic, in agreement with PCR-Ribotyping. Such epidemic strains were susceptible to vancomycin (MIC <= 0.5 mg/mL) and metronidazole (MIC <= 1 mg/mL), but not to moxifloxacin (MIC > 32 mg/mL). Moreover, they produced only the Toxin A and, additionally, the binary toxin. To our knowledge, this is the first reported outbreak referable to a tcdA+/tcdB-/cdt+ genotypic profile. In light of these results, T-MALDI is a valid and rapid approach for discovering and tracking outbreaks

Distribution of human Cytomegalovirus gB genotypes in samples from pediatric patients in Parma during the period 1995-2003

Background. Human Cytomegalovirus (HCMV) infection is a leading cause of developmental disability and late neurological sequelae in children. Several literature data indicate that HCMV pericapsidic glycoprotein B (gB) is highly immunogenic and is involved in virus-cell interaction.The gB gene has hypervariable regions producing four genotypes (gB1, gB2, gB3, gB4); however, the correlation between gB genotypes and HCMV infection outcome remains unclear. Objectives. The main goal of this study was that of evaluating the distribution of HCMV gB genotypes in samples from pediatric population in Parma with congenital, perinatal or post-natal infections, in order to find a correlation between viral gB genotypes and the clinical outcome of the infection. Study design. Forty eight urine samples, selected between 1999 and 2003 and stored at -80°C, underwent DNA extraction, nested PCR amplification of a gB gene region and restriction polymorphism analysis (RFLP). Results. The gB genotypes distribution in the considered pediatric population was as follows: gB1 was the most diffused (45.83%) followed by gB2 (22.92%), gB3 (16.67%) and gB4 (14.58%). Conclusions. In the considered population, gB1 was the most represented genotype and was often found in congenital and perinatal symptomatic infections, as well as in post-natal, asymptomatic infections

Active surveillance for carbapenemaseproducing Klebsiella pneumoniae and correlation with infection in subjects attending an Italian tertiary-care hospital: a 7-year retrospective study

Objectives The distribution of carbapenemase-producing Klebsiella pneumoniae (CPKP) phenotypes and genotypes in samples collected during 2011–2018 was evaluated. The association between patients with CPKP-positive rectal swab and those with CPKP infection, as well as the overall analysis of CPKP-infected patients, was performed. Setting The study was performed in a tertiary-care hospital located in Northern Italy. Participants Two groups were considered: 22 939 ‘atrisk’ patients submitted to active surveillance for CPKP detection in rectal swabs/stools and 1094 CPKP-infected patients in which CPKP was detected in samples other than rectal swabs. Results CPKP-positive rectal swabs were detected in 5% (1150/22 939). A CPKP infection was revealed in 3.1% (719/22 939) of patients: 582 with CPKP-positive rectal swab (50.6% of the 1150 CPKP-positive rectal swabs) and 137 with CPKP-negative rectal swab. The 49.4% (568/1150) of the patients with CPKP-positive rectal swab were carriers. The overall frequency of CPKP-positive patients (carriers and infected) was almost constant from 2012 to 2016 (excluding the 2015 peak) and then increased in 2017–2018. blaKPC was predominant followed by blaVIM. No difference was observed in the frequency of CPKP-positive rectal swab patients among the different material groups. Among the targeted carbapenemase genes, blaVIM was more significantly detected from urine than from other samples. Conclusions The high prevalence of carriers without evidence of infection, representing a potential reservoir of CPKP, suggests to maintain the guard about this problem, emphasising the importance of active surveillance for timely detection and separation of carriers, activation of contact precautions and antibiotic treatment guidance on suspicion of infection

Leptospira species and serovars identified by MALDI-TOF mass spectrometry after database implementation

Background: Leptospirosis, a spirochaetal zoonotic disease of worldwide distribution, endemic in Europe, has been recognized as an important emerging infectious disease, though yet it is mostly a neglected disease which imparts its greatest burden on impoverished populations from developing countries. Leptospirosis is caused by the infection with any of the more than 230 serovars of pathogenic Leptospira sp. In this study we aimed to implement the MALDI-TOF mass spectrometry (MS) database currently available in our laboratory with Leptospira reference pathogenic (L. interrogans, L. borgpetersenii, L. kirschneri, L. noguchii), intermediate (L. fainei) and saprophytic (L. biflexa) strains of our collection in order to evaluate its possible application to the diagnosis of leptospirosis and to the typing of strains. This was done with the goal of understanding whether this methodology could be used as a tool for the identification of Leptospira strains, not only at species level for diagnostic purposes, but also at serovar level for epidemiological purposes, overcoming the limits of serological and molecular conventional methods. Twenty Leptospira reference strains were analysed by MALDI-TOF MS. Statistical analysis of the protein spectra was performed by ClinProTools software. Results: The spectra obtained by the analysis of the reference strains tested were grouped into 6 main classes corresponding to the species analysed, highlighting species-specific protein profiles. Moreover, the statistical analysis of the spectra identified discriminatory peaks to recognize Leptospira strains also at serovar level extending previously published data. Conclusions: In conclusion, we confirmed that MALDI-TOF MS could be a powerful tool for research and diagnostic in the field of leptospirosis with broad applications ranging from the detection and identification of pathogenic leptospires for diagnostic purposes to the typing of pathogenic and non-pathogenic leptospires for epidemiological purposes in order to enrich our knowledge about the epidemiology of the infection in different areas and generate control strategies

Recent Advances in Unveiling the Role of Beta-Herpesviruses in Autoimmune Diseases

A dysregulated immune response can lead to recognition of self-antigens as non-selfantigens, leading to failure of the immune tolerance toward normal cells and tissues, and the consequent development of a variety of autoimmune diseases. Such diseases stem from a complex interaction between factors including the genetic background and environmental factors which can act as triggers of the dysregulated immune response, finally leading to tissue attack and loss of function or direct destruction. Autoimmune diseases affect up to 5% of the general population and include more than 80 chronic and progressive diseases, most of which are without recognized causes and specifically targeted therapies [1]. Among environmental triggers, herpesvirus infection is reportedly associated with the development of autoimmunity, including alpha- (Herpes simplex type 1, HSV-1), beta- (Human cytomegalovirus, HCMV, and Roseoloviruses), and gamma-herpesviruses (Epstein Barr virus, EBV) [2–6], based on their frequent presence in the affected patients and on the detection of specific and/or dysregulated immune response toward them [7]. In particular, beta-herpesvirus sub-family, includingHuman Cytomegalovirus (HCMV) and the Roseoloviruses Human herpesvirus-6A (HHV-6A), -6B (HHV-6B), and -7 (HHV-7), includes ubiquitous viruses with a long double strand DNA genome encoding more than 200 open reading frames, some of which produce factors that are able to directly interact with and modulate the immune response. Indeed, they have evolved an arsenal of immunomodulatory proteins and miRNAs, with several genes that are homologous to cell genes, most of which affect immune-related processes or controlling immune cell apoptosis [8]. All of them establish lifelong infections in the host, thanks to their ability to persist in a latent phase and eventually reactivate in specific cells. These characteristics, togetherwith theirwide cell/tissue tropism, render beta-herpesviruses good candidates as etiological agents of autoimmune diseases. However, a causative link between virus infection and autoimmune disease onset has not been conclusively established yet, nor the research has clarified whether those viruses are initiators of autoimmune diseases or simply bystanders, exacerbating the course of the pathology. In addition, beta-herpesviruses have mutualistic relationships and often are found co-reactivated in the host [7,9–11]; co-reactivation is associated with worse clinical outcome. Recently, the putative role of HCMV and HHV-6 infection has been investigated in autoimmune diseases, such as systemic sclerosis [12–15], multiple sclerosis [16,17], systemic lupus erythematosus [18], and Hashimoto’s Thyroiditis [19]. Nevertheless, though research studies have put light on several aspects of the betaherpesvirus replication and potential pathogenesis, no studies on the possible cooperation between beta-herpesviruses have been accomplished, nor has a clear-cut role been established for each individual virus in any of the hypothesized associated autoimmune diseases. Furthermore, being beta-herpesviruses considered poorly pathogenic viruses, the research program historically suffered from underfunding to the benefit of other more virulent viruses or more urgent pathologies. For instance, beta-herpesvirus infection could also play a role in the current viral pandemic in relation to the COVID-19 severity in patients with autoimmune diseases. In fact, a higher prevalence of symptomatic SARS-CoV- 2 infection has been detected among patients with autoimmune systemic diseases, such as systemic sclerosis [20]. In critically ill patients with COVID-19, a significantly high incidence of HCMV and HHV-6 reactivation was observed [21–23]. In this issue, the contributions from leading authors may provide: A comprehensive update on the status of the research on beta-herpesvirus and autoimmune diseases; Insight into serum or tissue markers of beta-herpesvirus infection; Studies highlighting the implementation of immunological and functional assays to understand the role of beta-herpesviruses in the etiopathogenesis of autoimmune diseases; Studies describing methods which can be used to distinguish HHV-6A from HHV-6B responses. The impact of deepening our understanding of the mechanisms by which betaherpesvirus can switch on the onset or the development of autoimmune diseases may help to reduce the risk to contract, slow, or block the progression of such diseases, opening the way for new, advanced therapies that are targeted to virus replication, viral products, or virus-induced factors inside the body. Taken together, this collection of reports will help to improve such understanding, ultimately expediting the design of appropriate diagnostic and therapeutic tools

Recent Advances in Unveiling the Role of Beta-Herpesviruses in Autoimmune Diseases

A dysregulated immune response can lead to recognition of self-antigens as non-self-antigens, leading to failure of the immune tolerance toward normal cells and tissues, and the consequent development of a variety of autoimmune diseases [...]