Inhibitory KIR2DL2 Receptor and HHV-8 in Classic or Endemic Kaposi Sarcoma

KIR2DL2, an inhibitory Killer cell Immunoglobulin-like Receptor (KIR), has been shown to predispose to the development of several herpesvirus-associated diseases by inhibiting the efficiency of Natural Killer (NK) cells against virus-infected cells. The aim of this observational study was to assess the prevalence of KIR2DL2 and Human Herpes Virus 8 (HHV8) in patients affected with classical and endemic Kaposi sarcoma (KS), as well as in controls. Blood samples collected from 17 Caucasian, HIV-negative, immunocompetent patients affected with classical KS (c-KS), 12 African, HIV-negative patients with endemic KS (e-KS), 83 healthy subjects and 26 psoriatic patients were processed for genotypization by PCR for two KIR alleles, such as KIR2DL2 and KIR2DL3 and analyzed for HHV-8 presence. The totality of both c-KS and e-KS patients presented HHV-8 infection, whereas HHV8 was found in 26.9% of psoriatic subjects and 19.3% of healthy subjects. KIR2DL2 was found in the 76.5% of c-KS subjects, while the receptor was found in 41.7% of the e-KS group, 34.6% of psoriatic patients and 43.4% of healthy controls (p<0.0001). A significantly higher prevalence of KIR2DL2 in c-KS patients than in all the other subjects was also confirmed comparing age-matched groups. Based on these results, the inhibitory KIR2DL2 genotype appears to be a possible cofactor which increases the risk of developing c-KS in HHV8-positive, immunocompetent subjects, while it seems less relevant in e-KS pathogenesis.

Phylogeographic analysis reveals an ancient East African origin of the human herpes simplexvirus 2 dispersal out-of-Africa.

Human herpes simplex virus 2 (HSV-2) is a globally ubiquitous, slow evolving DNA virus. HSV-2 genomic diversity can be divided into two main groups: an African lineage and worldwide lineage. Competing hypotheses have been put forth to explain the history of HSV-2. HSV-2 may have originated in Africa and then followed the first wave of human migration out of Africa between 50-100 kya. Alternatively, HSV-2 may have migrated out of Africa via the trans-Atlantic slave trade within the last 150-500 years. The lack of HSV-2 genomes from West and Central Africa, combined with a lack of molecular clock signal in HSV-2 has precluded robust testing of these competing hypotheses. Here, we expand the geographic sampling of HSV-2 genomes in order to resolve the geography and timing of divergence events within HSV-2. We analyze 65 newly sequenced HSV-2 genomes collected from primarily West and Central Africa along with 330 previously published genomes sampled over a 47-year period. Evolutionary simulations confirm that the molecular clock in HSV-2 is too slow to be detected using available data. However, phylogeographic analysis indicates that all biologically plausible evolutionary rates would place the ancestor of the worldwide lineage in East Africa, arguing against the trans-Atlantic slave trade as the source of worldwide diversity. The best supported evolutionary rates between 4.2x10-8 and 5.6x10-8 substitutions/site/year suggest a most recent common ancestor for HSV-2 around 90-120 kya and initial dispersal around 21.9-29.3 kya. These dates suggest HSV-2 left Africa during subsequent waves of human migration out of East Africa.

Multipathogen Detection in Patients with Respiratory Tract Infection: Identification of Non-respiratory Viruses Using Multiplex Real-time Polymerase Reaction

Background: Due to the overlapping clinical characteristics of respiratory tract infections (RTIs) and the unavailability of appropriate diagnostic techniques, the diagnosis of RTIs is controversial. Objectives: The study aimed to prompt the diagnosis of RTIs using commercial multiplex real-time PCR. Methods: The survey undertook for two years (2019 - 2020) on 144 flu-negative immunocompetent outpatients. Respiratory samples were examined by multiplex PCR assays. Results: Study population consisted of females (n = 77, 53.5%) and males (n = 67, 46.5%). The mean age was 42.8 ± 23.7 years. Thirty-one (21.5%) patients were infected with only one viral or bacterial infection. Eighty-two (57%) were infected with more than one pathogen. Ninety-five (37%) and 161 (62%) tests were positive for bacterial and viral pathogens, respectively. Community-acquired Pneumonia (CAP) and atypical CAP pathogens included 17% and 10% of respiratory specimens, respectively. The predominant pathogens consisted of Human Herpes Virus 7 (HHV-7) (n = 38, 15.5%), Epstein-Barr Virus (EBV) (n = 34, 13.8%), Mycoplasma pneumoniae (n = 24, 9.8%), and Human Herpes Virus 6 (HHV-6) (n = 21, 8.5%). There were associations between pathogen findings and special age categories. Fever, cough, dyspnea, and hemoptysis were associated with certain pathogens. There was no substantial difference between viral and bacterial Ct concerning gender, age group, and comorbidities. Conclusions: Multiplex diagnostic assays significantly increased the rate of appropriate diagnosis of respiratory pathogens. However, further investigation is needed to find non-respiratory viruses' significance in respiratory specimens of immunocompetent symptomatic patients.

Rare, disseminated Kaposi sarcoma in advanced HIV with high-burden pulmonary and skeletal involvement

We describe the case of a 30-year-old man who presented to our institution with hypoxia and widespread pulmonary infiltrates managed initially as COVID-19 before receiving a new diagnosis of HIV-associated Kaposi sarcoma (KS) with widespread pulmonary and skeletal involvement. Initial differential diagnoses included Pneumocystis jirovecii pneumonia, disseminated mycobacterial infection and bacillary angiomatosis. A bone marrow biopsy showed heavy infiltration by spindle cells, staining strongly positive for human herpes virus-8 (HHV-8) and CD34, suggesting symptomatic, disseminated KS as the unifying diagnosis. The patient commenced cytotoxic therapy with weekly paclitaxel, with a clinical and radiological response. To our knowledge, this case is among the most severe described in the literature, which we discuss, along with how COVID-19 initially hindered developing a therapeutic allegiance with the patient.

The Contribution of Human Herpes Viruses to γδ T Cell Mobilisation in Co-Infections

γδ T cells are activated in viral, bacterial and parasitic infections. Among viruses that promote γδ T cell mobilisation in humans, herpes viruses (HHVs) occupy a particular place since they infect the majority of the human population and persist indefinitely in the organism in a latent state. Thus, other infections should, in most instances, be considered co-infections, and the reactivation of HHV is a serious confounding factor in attributing γδ T cell alterations to a particular pathogen in human diseases. We review here the literature data on γδ T cell mobilisation in HHV infections and co-infections, and discuss the possible contribution of HHVs to γδ alterations observed in various infectious settings. As multiple infections seemingly mobilise overlapping γδ subsets, we also address the concept of possible cross-protection.

Clinical variants of chronic gastritis in childhood

Objective. To establish the features of various clinical variants of chronic gastritis in childhood. Material and methods. 415 children aged 617 years with chronic Hp-associated gastritis were examined. The clinical and anamnestic data, the results of laboratory, endoscopic and morphological studies of gastrobioptates were analyzed. Genetic typing of Hp was carried out with the determination of 16 pathogenicity factors. The persistence of human herpes viruses of types 6 and 8 and Epstein Barr viruses in the gastric mucosa was determined. Results. The clinical heterogeneity of chronic gastritis in children with the allocation of four topical variants was established: isolated duodenitis, duodenogastritis, antrum gastritis, pangastritis. It was found that with the first two, a high frequency of giardiasis is registered, with antrumgastritis and especially pangastritis, a significant contamination of the gastric mucosa with Hp is detected, mainly of CagA and VacA-positive strains. It is proved that the persistence of the type 6 human herpes virus does not affect the severity of inflammation, while the presence of the Epstein-Barr virus increases it. Colonization of the gastric mucosa by highly pathogenic Hp strains significantly increases the severity and activity of inflammation. It is shown that atrophy of the gastric mucosa in children is uncertain, and true atrophic gastritis occurs only in 0.61 % of cases. Conclusions. Chronic gastritis in children is a heterogeneous pathology, and its individual variants differ significantly in etiological factors including infectious, pathogenetic mechanisms and features of the morphology of gastric mucosa. This should be taken into account when carrying out medical support for patients.

Features of the course of acute decompensated ischemic heart failure and/or ongoing adverse left ventricular remodeling in patients with identified human herpes virus type 6

Objective. To determine serum levels of immunoglobulin M (IgM) and G (IgG) antibodies to human herpes virus type 6 (HHV-6) (anti-HHV-6) and features of clinical and morphological portrait in patients with acute decompensated heart failure (ADHF) of ischemic genesis and/or adverse left ventricular (LV) remodeling.Material and Methods. This open-label, nonrandomized, single-center, prospective trial was registered at clinicaltrials. gov (#NCT02649517) and comprised 25 patients (84% men) with ADHF and LV ejection fraction (EF) ≤ 40%. All patients underwent endomyocardial biopsy (EMB) with immunohistochemistry (IHC) analysis for the presence of HHV-6, compliment C1q, major histocompatibility complex of class II (MHC II), and B-lymphocyte antigen (CD19) as the markers of autoimmune reaction as well as the serum levels of anti-HHV-6 IgM and IgG. Serum levels of IgM and IgG were measured using enzymelinked immunosorbent assay (ELISA) with the calculation of positivity coefficient (PC) according to manufacturer instructions. The test results were interpreted as positive when PC value was greater than 0.8.Results. The endomyocardial biopsy study detected HHV-6 antigen expression in 15 (60%) out of 25 enrolled patients including 10 cases with diagnosed HHV-6-positive myocarditis and five patients with carriage of viruses. According to IHC, the autoimmune HHV-6 myocarditis was confirmed in three cases (30%). The data of ELISA (n = 18) detected anti-HHV-6 IgM in 5 patients (28%) and anti-HHV-6 IgG in 11 cases (61%). The simultaneous presence of both anti-HHV-6 IgM and IgG was detected in two patients (11%). In addition, anti-HHV-6 IgM and IgG were absent in two (11%) cases. Eight patients (44%) with HHV-6-positive myocarditis included three patients (17%) tested positive for serum anti-HHV-6 IgM, three patients (17%) tested positive for serum anti-HHV-6 IgG, and two patients (11%) who had nether anti-HHV-6 IgM nor anti-HHV-6 IgG in blood serum. Among virus carriers, one patient (20%) was tested positive for anti-HHV-6 IgM and four patients (80%) were tested positive for anti-HHV-6 IgG. The patients without HHV-6 antigen expression (n = 5, 28%) included one patient (5.6%) tested positive for anti-HHV-6 IgM and two patients (11%) tested positive for anti-HHV-6 IgG. The entire sample of patients was divided into two groups depending on the serum level of anti-HHV-6 IgM: group 1 comprised patients tested positive for anti-HHV-6 IgM (n = 5); group 2 comprised patients (n = 13) tested negative for anti-HHV-6 IgM. Clinical and instrumental parameters differed only in the duration of CHF history, which was greater in group 1 than in group 2 (11.0 [8.0; 12.0] vs. 22.5 [14.5; 75.5] months, respectively (p = 0.045). The groups did not significantly differ in the studied markers in myocardial tissue according to the results of IHC analysis. No associations were found between the severity of HHV-6 antigen expression and serum levels of anti-HHV-6 IgM and IgG.Conclusion. Patients with ADHF and/or adverse LV remodeling after complete myocardial revascularization had higher percentage of HHV-6 antigen expression whose severity was not associated with the serum levels of anti-HHV-6 IgM and IgG.