CD34+DNAM-1brightCXCR4+ haemopoietic precursors circulate after chemotherapy, seed lung tissue and generate functional innate-like T cells and NK cells.

Background: There is little information on the trajectory and developmental fate of Lin-CD34+DNAM-1bright CXCR4+ progenitors exiting bone marrow during systemic inflammation. Objective: To study Lin-CD34+DNAM-1bright CXCR4+ cell circulation in cancer patients, to characterize their entry into involved lung tissue and to characterize their progenies. Methods: Flow cytometric analysis of PBMC from 18 patients with lung cancer on samples collected immediately before the first and the second treatment was performed to study Lin-CD34+DNAM-1bright CXCR4+ precursors. Precursors were purified (>99%) and cultured in vitro from all patients. Paired PBMC and tissue samples from patients undergoing tumor resection were analyzed by flow cytometry to assess tissue entry and compare phenotype and developmental potential of Lin-CD34+DNAM-1bright CXCR4+ cells in both compartments. Results: Significant circulation of Lin-CD34+DNAM-1bright CXCR4+ precursors was observed 20d after the first treatment. Precursors express CXC3CR1, CXCR3, CXCR1 consistent with travel towards inflamed tissues. Flowcytometric analysis of lung tissue samples showed precursor presence in all patients in tumor and neighboring uninvolved areas. Successful purification and in vitro culture from both blood and lung tissue generates a minor proportion of maturing NK cells (<10%) and a predominant proportion (>85%) of α/ß T-progenies with innate-like phenotype expressing NKG2D,NKp30,DNAM-1. Innate-like maturing T-cells in vitro are cytotoxic, can be triggered via NKR/TCR co-stimulation and display broad spectrum Th1,Th2 and Th1/Th17 cytokine production. Conclusion: In advanced stage lung cancer CD34+DNAM-1brightCXCR4+ inflammatory precursors increase upon treatment, enter involved tissues, generate functional progenies and may thus represent an additional player contributing to immune balance in the highly SDF-1/CXCR4-biased pro-metastatic tumor microenvironment.

Neutralizing monoclonal antibodies for the prevention of severe COVID-19: a retrospective study during Omicron BA.1 variant surge.

Among treatment options for Coronavirus disease 2019 (COVID-19), monoclonal antibodies (mAbs) showed to be effective in preventing disease progression, but real-world data during the Omicron variant surge are still lacking. Multicentre retrospective study evaluating the effectiveness of sotrovimab and casirivimab-imdevimab in fragile patients with mild SARS-CoV-2 infection between November 2021 and March 2022. Unfavourable outcome was defined as increased need for oxygen supplementation and/or death. Of 268 study-participants, 12 (4.48%) previously needed supplemental oxygen, while 6 (2.24%) had active solid neoplasia (2.24%); 186 (69%) have previously received SARS-CoV-2 vaccination. Overall, 22 (8%) had unfavourable outcomes (42% versus 6% of patients with and without previous oxygen need and 50% versus 7% of patients with and without active solid neoplasia). Both supplemental oxygen therapy before SARS-CoV-2 infection and solid malignant tumour have shown to be risk factors for treatment failure. Log-rank test did not identify differences between sotrovimab and casirivimab-imdevimab treatment. Despite diffusion of Omicron variant, the rate of unfavourable outcome was higher than expected. The presence of underlying risk factors, including solid cancer and previous oxygen therapy are independently associated with risk of COVID-19 progression, suggesting the need for antiviral treatments not limited to mAbs and implementation of vaccine campaign.

Immune Checkpoint Inhibitors in Patients With Cancer and Infection by Hepatitis B or C Virus: A Perspective Through the Results of a European Survey.

Introduction: Patients with cancer and hepatitis B virus (HBV) or hepatitis C virus (HCV) infection are underrepresented in several clinical trials testing immune checkpoint inhibitors (ICIs). Consequently, safety and efficacy of ICI therapy in this population have not been completely defined. We aimed to evaluate the attitudes of oncologists on this topic. Methods: We conducted a 14-item European anonymous online survey. Results: Physicians from 56 oncology departments (26 from Italy, 15 from France, and 15 from Spain) took part in the survey. They mainly used to prescribe ICIs for treating patients with lung cancer, melanoma, and renal cell carcinoma. Of them, 95% recognized the need for specific guidelines addressing the management of patients with cancer and HBV or HCV treated with ICIs. Just 63% of the respondents screened patients for HBV and HCV status before ICIs initiation, although the risk of immune-related hepatotoxicity or viral reactivation was a major concern for most of them. Only 9% of the surveyed oncologists considered HBV and HCV infection a major exclusion criterion for receiving ICIs. Furthermore, 29% of the respondents would start a prophylactic treatment of active infection at ICIs initiation. Conclusions: ICIs administration in patients with cancer and HBV or HCV infection is of concern for most of the surveyed European oncologists. Nonetheless, active screening and treatment of viral hepatitis should be improved. Data in this specific setting are needed for an evidence-based management and should be generated by broadening inclusion criteria of clinical trials to allow the enrollment of patients with HBV and HCV.

Clinical Benefits of the Socket Shield Technique Associated with Anatomical Transmucosal Implant Components: A Case Report

One of the key factors in determining the esthetic success of implant-supported prostheses in the esthetic zone is the preservation of the natural architecture of the peri-implant tissues. A case replacing two maxillary lateral incisors with reduced buccal cortical bone by means of implant-supported crowns was illustrated. The socket shield technique was adopted to conserve the tissue volume, guided surgery was used to manage the optimal implant insertion, and anatomically shaped transmucosal implant components were selected to shape peri-implant soft tissues with the ideal emergence profiles and allow for direct digital impressions without scan bodies. The association of immediate implantation, guided surgery, socket shield technique, anatomically shaped transmucosal implant components, and digital impressions without scan bodies was used to achieve a successful rehabilitation with healthy, stable, and anatomically shaped peri-implant tissues.

Adaptive NK cell response to human cytomegalovirus: Facts and open issues.

Human cytomegalovirus (HCMV) infection exerts broad effects on the immune system. These include the differentiation and persistent expansion of a mature NK cell subset which displays a characteristic phenotypic and functional profile hallmarked by expression of the HLA-E-specific CD94/NKG2C activating receptor. Based on our experience and recent advances in the field, we overview the adaptive features of the NKG2C+ NK cell response, discussing observations and open questions on: (a) the mechanisms and influence of viral and host factors; (b) the existence of other NKG2C- NK cell subsets sharing adaptive features; (c) the development and role of adaptive NKG2C+ NK cells in the response to HCMV in hematopoietic and solid organ transplant patients; (d) their relation with other viral infections, mainly HIV-1; and (e) current perspectives for their use in adoptive immunotherapy of cancer.

Intermediate monocytes expansion and homing markers expression in COVID-19 patients associate with kidney dysfunction.

Patients with severe SARS-CoV-2 infection have an overwhelming inflammatory response characterized by remarkable organs monocyte infiltration. We performed an immunophenotypic analysis on circulating monocytes in 19 COVID-19 patients in comparison with 11 naïve HIV-1 patients and 10 healthy subjects. Reduced frequency of classical monocytes and increased frequency of intermediate monocytes characterized COVID-19 patients with respect to both HIV naïve patients and healthy subjects. Intensity of C-C motif chemokine receptor 2 (CCR2) monocyte expression highly correlated with parameters of kidney dysfunction. Our data indicate that highly activated monocytes of COVID-19 patients may be pathogenically associated with the development of renal disease.

High-temporal resolution profiling reveals distinct immune trajectories following the first and second doses of COVID-19 mRNA vaccines.

Knowledge of the mechanisms underpinning the development of protective immunity conferred by mRNA vaccines is fragmentary. Here, we investigated responses to coronavirus disease 2019 (COVID-19) mRNA vaccination via high-temporal resolution blood transcriptome profiling. The first vaccine dose elicited modest interferon and adaptive immune responses, which peaked on days 2 and 5, respectively. The second vaccine dose, in contrast, elicited sharp day 1 interferon, inflammation, and erythroid cell responses, followed by a day 5 plasmablast response. Both post-first and post-second dose interferon signatures were associated with the subsequent development of antibody responses. Yet, we observed distinct interferon response patterns after each of the doses that may reflect quantitative or qualitative differences in interferon induction. Distinct interferon response phenotypes were also observed in patients with COVID-19 and were associated with severity and differences in duration of intensive care. Together, this study also highlights the benefits of adopting high-frequency sampling protocols in profiling vaccine-elicited immune responses.

Next Generation Immuno-Oncology Strategies: Unleashing NK Cells Activity.

In recent years, immunotherapy has become a powerful therapeutic option against multiple malignancies. The unique capacity of natural killer (NK) cells to attack cancer cells without antigen specificity makes them an optimal immunotherapeutic tool for targeting tumors. Several approaches are currently being pursued to maximize the anti-tumor properties of NK cells in the clinic, including the development of NK cell expansion protocols for adoptive transfer, the establishment of a favorable microenvironment for NK cell activity, the redirection of NK cell activity against tumor cells, and the blockage of inhibitory mechanisms that constrain NK cell function. We here summarize the recent strategies in NK cell-based immunotherapies and discuss the requirement to further optimize these approaches for enhancement of the clinical outcome of NK cell-based immunotherapy targeting tumors.

Clinical and Radiologic Evaluation of a Fully Tapered Implant with Immediate Placement in the Esthetic Zone: A Prospective Case Series Study.

A fully tapered implant was recently introduced to increase primary stability and to be used in challenging situations. Twenty single implants were inserted in maxillary postextraction sockets, from premolar to premolar, and immediately restored. Marginal bone level (MBL) and probing depth (PD) were evaluated over a 12-month follow-up period. All implants osseointegrated, achieving a success rate of 100%. The difference in MBL between implant placement and 1 year later was 0.20 ± 0.04 mm, while PD was 2.82 ± 0.51 mm at 1 year. The data reported here support the use of a fully tapered implant for immediate placement and immediate provisionalization for single-tooth replacements in the esthetic area.

Herpes Simplex Virus 1 (HSV-1) Reactivation in Critically Ill COVID-19 Patients: A Brief Narrative Review.

Systemic or pulmonary reactivations of herpes simplex virus 1 (HSV-1) have been reported in critically ill patients with COVID-19, posing a dilemma for clinicians in terms of their diagnostic and clinical relevance. Prevalence of HSV-1 reactivation may be as high as > 40% in this population, but with large heterogeneity across studies, likely reflecting the different samples and/or cut-offs for defining reactivation. There is frequently agreement on the clinical significance of HSV-1 reactivation in the presence of severe manifestations clearly attributable to the virus. However, the clinical implications of HSV-1 reactivations in the absence of manifest signs and symptoms remain controversial. Our review aims at providing immunological background and at reviewing clinical findings on HSV-1 reactivations in critically ill patients with COVID-19.

Persistence of Unintegrated HIV DNA Associates With Ongoing NK Cell Activation and CD34+DNAM-1brightCXCR4+ Precursor Turnover in Vertically Infected Patients Despite Successful Antiretroviral Treatment.

The quantification of proviral DNA is raising interest in view of clinical management and functional HIV eradication. Measures of all unintegrated HIV DNA (uDNA) forms in infected reservoir cells provides information on recent replication events that is not found from other proviral DNA assays. To evaluate its actual relevance in a cohort of perinatally-infected adult HIV patients (PHIV), we studied how peripheral blood mononuclear cell uDNA levels correlated with total HIV DNA (tDNA) and with overall replication or innate immune control parameters including NK cell activation/exhaustion and lymphoid turnover. Twenty-two PHIV were included, with successfully controlled HIV (HIV RNA <50 copies/mL) on combined antiretroviral therapy for mean of 8.7 ± 3.9 years. uDNA accounted for 16 [5.2-83.5] copies/µg and was strongly correlated with tDNA (ρ=0.700, p=0.001). Flow cytometric analysis of peripheral NK cells showed that CD69 expression was directly correlated uDNA (p=0.0412), but not with tDNA. Interestingly, CD56-CD16+NK cells which include newly described inflammatory precursors and terminally differentiated cells were directly correlated with uDNA levels (p<0.001), but not with tDNA, and an inverse association was observed between the proportion of NKG2D+ NK cells and uDNA (ρ=-0.548, p=0.015). In addition, CD34+DNAM-1brightCXCR4+ inflammatory precursor frequency correlated directly with uDNA levels (ρ=0.579, p=0.0075). The frequencies of CD56-CD16+ and CD34+DNAM-1brightCXCR4+ cells maintained association with uDNA levels in a multivariable analysis (p=0.045 and p=0.168, respectively). Thus, control of HIV-1 reservoir in aviremic patients on ART is an active process associated with continuous NK cell intervention and turnover, even after many years of treatment. Quantification of linear and circular uDNA provides relevant information on the requirement for ongoing innate immune control in addition to ART, on recent replication history and may help stratify patients for functional HIV eradication protocols with targeted options.

Incidence and immunomic features of apyretic COVID-19 in patients affected by solid tumors: a prospective cohort study.

BACKGROUND AND RATIONALE: Little is known about SARS-CoV-2 seroconversion in asymptomatic patients affected by solid cancer, and whether it is associated with specific transcriptomics changes in peripheral blood mononuclear cells (PBMC). METHODS: Patients affected by solid cancer treated in a top comprehensive cancer center in Italy during the first COVID-19 pandemic wave, and negative for COVID-19-symptoms since the first detection of COVID-19 in Italy, were prospectively evaluated by SARS-CoV-2 serology in the period between April 14th and June 23rd 2020. Follow-up serologies were performed, every 21-28 days, until August 23rd 2020. All SARS-CoV-2 IgM + patients underwent confirmatory nasopharyngeal swab (NPS). PBMCs from a subset of SARS-CoV-2 IgM + patients were collected at baseline, at 2 months, and at 7 months for transcriptome sequencing. RESULTS: SARS-CoV-2 serology was performed on 446 of the 466 recruited patients. A total of 14 patients (3.14%) tested positive for at least one SARS-CoV-2 immunoglobulin in the period between April 14th and August 23rd 2020. Incidence of SARS-CoV-2 IgM decreased from 1.48% in the first month of the accrual to 0% in the last month. Viral RNA could not be detected in any of the NPS. PBMC serial transcriptomic analysis showed progressive downregulation of interleukin 6 upregulated signatures, chemokine-mediated signaling and chemokine-chemokine receptor KEGG pathways. B- and T-cell receptor pathways (p-values = 0.0002 and 0.017 respectively) were progressively upregulated. CONCLUSIONS: SARS-CoV-2 seroconversion rate in asymptomatic patients affected by solid cancer is consistent with that of asymptomatic COVID-19 assessed in the general population through NPS at the peak of the first wave. Transcriptomic features over time in IgM + asymptomatic cases are suggestive of previous viral exposure.

Mind the gap: IgG4-related disease mimicking infectious cerebral mass lesions.

BACKGROUND: Cerebral intraparenchymal masses represent usually a neoplastic, or infectious differential diagnostic workup in neurology or infectious disease units. CASE PRESENTATION: Our patient was an 82-year-old male presenting with seizures, cerebral masses and a history of past treated pulmonary tuberculosis. Initial workup included a differential diagnosis of an infectious mass/multiple abscess. After exclusion of infectious or primary neoplastic origins by negative HIV serology, the absence of immune suppression, endocarditic lesions, negative results of blood cultures and bronchoalveolar lavage, negative cerebrospinal fluid workout on spinal tap led to exclusion of infectious causes. A surgical procedure was performed to access one of the lesions. This yielded a firm, cyst-like mass of histiocytic granulomatous tissue with a conspicuous plasmacellular component and a relevant IgG4 plasmacellular component consistent with IgG4-related disease. Steroid treatment determined conspicuous improvement and led to discharge of the patient. CONCLUSION: Parenchymal IgG4-related disease may be included as a new entity in the differential diagnosis of single or multiple cerebral masses in addition to infectious or neoplastic etiology.

Reactivation of Herpes Simplex Virus Type 1 (HSV-1) Detected on Bronchoalveolar Lavage Fluid (BALF) Samples in Critically Ill COVID-19 Patients Undergoing Invasive Mechanical Ventilation: Preliminary Results from Two Italian Centers.

Reactivation of herpes simplex virus type 1 (HSV-1) has been described in critically ill patients with coronavirus disease 2019 (COVID-19) pneumonia. In the present two-center retrospective experience, we primarily aimed to assess the cumulative risk of HSV-1 reactivation detected on bronchoalveolar fluid (BALF) samples in invasively ventilated COVID-19 patients with worsening respiratory function. The secondary objectives were the identification of predictors for HSV-1 reactivation and the assessment of its possible prognostic impact. Overall, 41 patients met the study inclusion criteria, and 12/41 patients developed HSV-1 reactivation (29%). No independent predictors of HSV-1 reactivation were identified in the present study. No association was found between HSV-1 reactivation and mortality. Eleven out of 12 patients with HSV-1 reactivation received antiviral therapy with intravenous acyclovir. In conclusion, HSV-1 reactivation is frequently detected in intubated patients with COVID-19. An antiviral treatment in COVID-19 patients with HSV-1 reactivation and worsening respiratory function might be considered.

The Longest Persistence of Viable SARS-CoV-2 With Recurrence of Viremia and Relapsing Symptomatic COVID-19 in an Immunocompromised Patient-A Case Study.

BACKGROUND: Immunocompromised patients show prolonged shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal swabs. We report a case of prolonged persistence of viable SARS-CoV-2 associated with clinical relapses of coronavirus disease 2019 (COVID-19) in a patient with mantle cell lymphoma who underwent treatment with rituximab, bendamustine, cytarabine with consequent lymphopenia and hypogammaglobulinemia. METHODS: Nasopharyngeal swabs and blood samples were tested for SARS-CoV-2 by real-time polymerase chain reaction (RT-PCR). On 5 positive nasopharyngeal swabs, we performed viral culture and next-generation sequencing. We analyzed the patient's adaptive and innate immunity to characterize T- and NK-cell subsets. RESULTS: SARS-CoV-2 RT-PCR on nasopharyngeal swabs samples remained positive for 268 days. All 5 performed viral cultures were positive, and genomic analysis confirmed a persistent infection with the same strain. Viremia resulted positive in 3 out of 4 COVID-19 clinical relapses and cleared each time after remdesivir treatment. The T- and NK-cell dynamic was different in aviremic and viremic samples, and no SARS-CoV-2-specific antibodies were detected throughout the disease course. CONCLUSIONS: In our patient, SARS-CoV-2 persisted with proven infectivity for >8 months. Viremia was associated with COVID-19 relapses, and remdesivir treatment was effective in viremia clearance and symptom remission, although it was unable to clear the virus from the upper respiratory airways. During the viremic phase, we observed a low frequency of terminal effector CD8+ T lymphocytes in peripheral blood; these are probably recruited in inflammatory tissue for viral eradication. In addition, we found a high level of NK-cell repertoire perturbation with relevant involvement during SARS-CoV-2 viremia.

Characterization of T lymphocytes in severe COVID-19 patients.

In this observational study, 13 patients with severe COVID-19 and 10 healthy controls were enrolled. The data concerning the analysis of circulating T cells show that, in severe COVID-19 patients, the expansion of these cell compartments is prone to induce antibody response, inflammation (CCR4+ and CCR6+ TFH) and regulation (CD8+ Treg). This pathogenic mechanism could lead us to envision a possible new form of biological target therapy.

Extensive activation, tissue trafficking, turnover and functional impairment of NK cells in COVID-19 patients at disease onset associates with subsequent disease severity.

The SARS-CoV-2 infection causes severe respiratory involvement (COVID-19) in 5-20% of patients through initial immune derangement, followed by intense cytokine production and vascular leakage. Evidence of immune involvement point to the participation of T, B, and NK cells in the lack of control of virus replication leading to COVID-19. NK cells contribute to early phases of virus control and to the regulation of adaptive responses. The precise mechanism of NK cell dysregulation is poorly understood, with little information on tissue margination or turnover. We investigated these aspects by multiparameter flow cytometry in a cohort of 28 patients hospitalized with early COVID-19. Relevant decreases in CD56brightCD16+/- NK subsets were detected, with a shift of circulating NK cells toward more mature CD56dimCD16+KIR+NKG2A+ and "memory" KIR+CD57+CD85j+ cells with increased inhibitory NKG2A and KIR molecules. Impaired cytotoxicity and IFN-γ production were associated with conserved expression of natural cytotoxicity receptors and perforin. Moreover, intense NK cell activation with increased HLA-DR and CD69 expression was associated with the circulation of CD69+CD103+ CXCR6+ tissue-resident NK cells and of CD34+DNAM-1brightCXCR4+ inflammatory precursors to mature functional NK cells. Severe disease trajectories were directly associated with the proportion of CD34+DNAM-1brightCXCR4+ precursors and inversely associated with the proportion of NKG2D+ and of CD103+ NK cells. Intense NK cell activation and trafficking to and from tissues occurs early in COVID-19, and is associated with subsequent disease progression, providing an insight into the mechanism of clinical deterioration. Strategies to positively manipulate tissue-resident NK cell responses may provide advantages to future therapeutic and vaccine approaches.

Bronchoalveolar lavage fluid characteristics and outcomes of invasively mechanically ventilated patients with COVID-19 pneumonia in Genoa, Italy.

BACKGROUND: The primary objective of the study is to describe the cellular characteristics of bronchoalveolar lavage fluid (BALF) of COVID-19 patients requiring invasive mechanical ventilation; the secondary outcome is to describe BALF findings between survivors vs non-survivors. MATERIALS AND METHODS: Patients positive for SARS-CoV-2 RT PCR, admitted to ICU between March and April 2020 were enrolled. At ICU admission, BALF were analyzed by flow cytometry. Univariate, multivariate and Spearman correlation analyses were performed. RESULTS: Sixty-four patients were enrolled, median age of 64 years (IQR 58-69). The majority cells in the BALF were neutrophils (70%, IQR 37.5-90.5) and macrophages (27%, IQR 7-49) while a minority were lymphocytes, 1%, TCD3+ 92% (IQR 82-95). The ICU mortality was 32.8%. Non-survivors had a significantly older age (p = 0.033) and peripheral lymphocytes (p = 0.012) were lower compared to the survivors. At multivariate analysis the percentage of macrophages in the BALF correlated with poor outcome (OR 1.336, CI95% 1.014-1.759, p = 0.039). CONCLUSIONS: In critically ill patients, BALF cellularity is mainly composed of neutrophils and macrophages. The macrophages percentage in the BALF at ICU admittance correlated with higher ICU mortality. The lack of lymphocytes in BALF could partly explain a reduced anti-viral response.