Impact of belimumab therapy on the quality of life in patients with systemic lupus erythematosus: A cohort study.

Systemic lupus erythematosus (SLE) is a chronic and extremely disabling connective-tissue autoimmune disease with a tremendous impact on the quality of life (QoL). Belimumab, a B-lymphocyte-stimulator-specific inhibitor, is the first biologic drug approved as add-on therapy in patients with active, refractory auto-antibody-positive SLE.The impact of belimumab on the QoL of SLE patients was evaluated using a generic questionnaire short-form health survey 36 (SF-36) and the disease-specific questionnaire SLE-specific quality of life (SLEQoL).The Italian version of the SLEQoL and the SF-36 were administered to 46 SLE patients before and after 6 months of belimumab therapy. The control population consisted of 40 age-matched healthy individuals. The questionnaires were completed before and after belimumab treatment and the results were compared using the Wilcoxon signed-rank test. In addition, data from healthy controls and SLE patients were compared using the Mann-Whitney test. Dichotomous variables were compared using Fisher's exact test.For SLE patients, the addition of belimumab to their therapeutic regimen significantly improved their health-related QoL (HRQoL), according to the results of the SF-36 and SLEQoL. The comparison of the data obtained before and after belimumab treatment showed a decrease in all six SLEQoL domains and an increase in all eight SF-36 domains. Moreover, treatment led to a reduction in the median prednisone dose, to 0 mg/day (IQR 0-4.5 mg/day). Before belimumab therapy, SLE patients had a worse HRQoL than the control group, based on both questionnaires, but after belimumab treatment the outcome scores between SLE patients and controls were similar, suggesting that belimumab therapy resulted in a strong improvement in HRQoL. These findings were supported by a decrease in the SELENA-SLEDAI score, a measure of disease activity.In addition to clinical remission and low disease activity, the goals of an innovative therapeutic strategy for SLE should include the attainment of a good HRQoL. Our study demonstrates that the combined use of the SF-36 and SLEQoL questionnaires can provide clinicians with a better understanding of the HRQoL of SLE patients.

Halting the vicious cycle within the multiple myeloma ecosystem: blocking JAM-A on bone marrow endothelial cells restores angiogenic homeostasis and suppresses tumor progression.

Interactions of malignant multiple myeloma (MM) plasma cells (MM-cells) with the microenvironment control MM-cell growth, survival, drug-resistance and dissemination. As in MM microvascular density increases in the bone marrow (BM), we investigated whether BM MM endothelial cells (MMECs) control disease progression via the junctional adhesion molecule A (JAM-A). Membrane and cytoplasmic JAM-A levels were upregulated in MMECs in 111 newly diagnosed (NDMM) and 201 relapsed-refractory (RRMM) patients compared to monoclonal gammopathy of undetermined significance (MGUS) and healthy controls. Elevated membrane expression of JAM-A on MMECs predicted poor clinical outcome. Mechanistically, addition of recombinant JAM-A to MMECs increased angiogenesis whereas its inhibition impaired angiogenesis and MM growth in 2D and 3D in vitro cell culture and chorioallantoic membrane-assays. To corroborate these findings, we treated MM bearing mice with JAM-A blocking mAb and demonstrated impaired MM progression corresponding to decreased MM-related vascularity. These findings support JAM-A as an important mediator of MM progression through facilitating MM-associated angiogenesis. Collectively, elevated JAM-A expression on bone marrow endothelial cells is an independent prognostic factor for patient survival in both NDMM and RRMM. Blocking JAM-A restricts angiogenesis in vitro, in embrio and in vivo and represents a suitable druggable molecule to halt neoangiogenesis and MM progression.

PDCD1 and IFNL4 genetic variants and risk of developing hepatitis C virus-related diseases.

BACKGROUND: Genetic variants of IFNL4 and PDCD1 genes have been shown to influence the spontaneous clearance of hepatitis C virus (HCV) infection. We investigated the IFNL4 rs12979860 and the PDCD1 polymorphisms in 734 HCV-positive patients, including 461 cases with liver disease of varying severity and 273 patients with lymphoproliferative disorders to determine the association of these genes with patient's outcome. METHODS: Expression levels of PDCD1 mRNA encoded by haplotypes were investigated by quantitative PCR in hepatocellular carcinoma (HCC) tissue and peripheral blood mononuclear cells. Flow cytometry was used to detect PD-1 and its ligand PD-L1. RESULTS: The frequency of IFNL4 rs12979860 C/T or T/T genotypes was significantly higher in patients with HCV-related diseases than blood donors (P < .0001). Patients expressing the IFNλ4 variant with one amino acid change that reduces IFNλ4 secretion was found increased in frequency in HCV-related diseases compared to HCC PDCD1 mRNA levels in HCC tissue were significantly higher in cases carrying the PD-1.3 A or the PD-1.7 G allele (P = .0025 and P = .0167). Linkage disequilibrium (LD) between PD-1.3 and IFNL4 was found in patients with mixed cryoglobulinaemia (MC) only (LD = 0 in HCC; LD = 72 in MC). PBMCs of MC patients expressed low levels of PD-L1 in CD19+IgM+B cells and of PD-1 in CD4+T cells suggesting the involvement of regulatory B cell-T cell interaction to the pathogenesis of MC. CONCLUSION: Collectively, our data indicate an important contribution of IFNλ4 expression to the development of HCV-related HCC and an epistatic contribution of IFNL4 and PDCD1 in MC. LAY SUMMARY: Studies of IFNL4 and PDCD1 genes are helpful to better understand the role of host genetic factors and immune antigens influencing the outcome of HCV-related diseases. Our data support an association between the expression of IFNλ4, which prevents the expression of IFNλ3, with all the different HCV-related diseases studied, and besides, evidence that a higher IFNλ4 expression is associated with hepatocellular at a younger age. The expression pattern of low PD-L1 on B cells and high PD-1 on CD4+T-cells in patients with HCV-positive cryoglobulinaemia suggests a critical role of the PD-1/PD-L1 signaling in modulating B cell-T cell interaction in this lymphoproliferative disease.

Immune Checkpoint Inhibitor-Related Myositis: From Biology to Bedside.

: Immune checkpoint inhibitor (ICI)-related inflammatory diseases, including polymyositis (PM) and dermatomyositis (DM), in patients suffering from neoplastic disorders represent a medical challenge. The treatment of these conditions has taken on new urgency due to the successful and broad development of cancer-directed immunological-based therapeutic strategies. While primary and secondary PM/DM phenotypes have been pathophysiologically characterized, a rational, stepwise approach to the treatment of patients with ICI-related disease is lacking. In the absence of high-quality evidence to guide clinical judgment, the available data must be critically assessed. In this literature review, we examine partially neglected immunological and clinical findings to obtain insights into the biological profiles of ICI-related PM/DM and potential treatment options. We show that differential diagnosis is essential to stratifying patients according to prognosis and therapeutic impact. Finally, we provide a comprehensive assessment of druggable targets and suggest a stepwise patient-oriented approach for the treatment of ICI-related PM/DM.

Ocular sarcoidosis: clinical experience and recent pathogenetic and therapeutic advancements.

PURPOSE: To describe the ocular manifestations in a cohort of patients with systemic sarcoidosis (SS). Recent advances in the pathophysiology, diagnosis, and therapy of SS are also discussed. METHODS: Data from 115 Italian patients diagnosed between 2005 and 2016 were retrospectively reviewed. All but the first 17 patients underwent a comprehensive ophthalmologic examination. The diagnosis was based on clinical features, the demonstration of non-caseating granulomas in biopsies from involved organs, and multiple imaging techniques. Data on broncho-alveolar lavage fluid analysis, calcemia, calciuria, serum angiotensin-converting enzyme levels and soluble interleukin-2 receptor levels were retrieved when available. RESULTS: Ocular involvement, detected in 33 patients (28.7%), was bilateral in 29 (87.9%) and the presenting feature in 13 (39.4%). Anterior uveitis was diagnosed in 12 patients (36.4%), Löfgren syndrome and uveoparotid fever in one patient each (3%), intermediate uveitis in 3 patients (9.1%), posterior uveitis in 7 (21.2%), and panuveitis in 9 (27.3%). First-line therapy consisted of corticosteroids, administered as eyedrops (10 patients), sub-Tenon's injections (1 patient), intravitreal implants (9 patients), or systemically (23 patients). Second-line therapy consisted of steroid-sparing immunosuppressants, including methotrexate (10 patients) and azathioprine (10 patients). Based on pathogenetic indications that tumor necrosis factor (TNF)-α is a central mediator of granuloma formation, adalimumab, targeting TNF-α, was employed in 6 patients as a third-line agent for severe/refractory chronic sarcoidosis. CONCLUSION: Uveitis of protean type, onset, duration, and course remains the most frequent ocular manifestation of SS. Diagnostic and therapeutic advancements have remarkably improved the overall visual prognosis. An ophthalmologist should be a constant component in the multidisciplinary approach to the treatment of this often challenging but intriguing disease.

Common Variable Immunodeficiency and Gastric Malignancies.

Common variable immunodeficiency (CVID) is an immunodeficiency disorder with a high incidence of gastrointestinal manifestations and an increased risk of gastric carcinoma and lymphoma. This review discusses the latest advancements into the immunological, clinical and diagnostic aspects of gastric malignancies in patients with CVID. The exact molecular pathways underlying the relationships between CVID and gastric malignancies remain poorly understood. These include genetics, immune dysregulation and chronic infections by Helicobacter pylori. Further studies are needed to better stratify the risk for cancer in these patients, to elaborate surveillance programs aimed at preventing these complications, and to develop new and more effective therapeutic approaches.

Dendritic cells accumulate in the bone marrow of myeloma patients where they protect tumor plasma cells from CD8+ T-cell killing.

Many researchers have speculated that the clinical progression from monoclonal gammopathy of undetermined significance (MGUS) to multiple myeloma (MM) is driven by defects in dendritic cell (DC) function. However, evidence supporting this assumption is controversial, and no mechanism for the putative DC dysfunction has been demonstrated thus far. We studied DC subsets from the bone marrow of MM patients compared with those of MGUS patients and control subjects. We found that myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) accumulate in the bone marrow during the MGUS-to-MM progression. After engulfment of apoptotic tumor plasma cells via CD91, bone marrow mDCs and pDCs mature and are able to activate tumor-specific CD8(+) T cells. However, by interacting directly with CD28 on live (nonapoptotic) tumor plasma cells, bone marrow mDCs downregulate the expression of proteasome subunits in these cells, thus enabling their evasion from human leukocyte antigen (HLA) class I-restricted CD8(+) T-cell killing. These results suggest that DCs play a dual, but opposing, role in MM: for one, DCs activate CD8(+) T cells against tumor plasma cells and, for the other, DCs protect tumor plasma cells from CD8(+) T-cell killing. This information should be taken into account in designing immunotherapy approaches to enhance immune surveillance in MGUS and to break down immune tolerance in MM.

Myeloma cells act as tolerogenic antigen-presenting cells and induce regulatory T cells in vitro.

Regulatory T cells (Tregs) are essential for maintenance of self-tolerance; however, tumor cells can exploit the tolerance to escape the immune system. We investigated the Tregs frequency in patients with multiple myeloma (MM) and in those with monoclonal gammopathy of undetermined significance (MGUS), and found that CD4(+) FoxP3(+) and CD8(+) FoxP3(+) Tregs were significantly increased in patients with MM and correlated with the active phase. Both Tregs subsets were expanded in cocultures of CD3(+) lymphocytes and fresh CD138(+) MM plasma cells or RPMI8226 and U266 cell lines and functioned as natural (n) and inducible (i) Tregs insofar as they inhibited the proliferation of stimulated CD3 lymphocytes via contact-dependent and contact-independent pathways. Induction of Tregs by MM plasma cells required a contact-dependent pathway, implying antigen recognition by T cells. MM plasma cells acted as immature and tolerogenic antigen-presenting cells (APCs), in that they displayed low CD80/CD86 expression associated with a phagocytic activity. By acting as immature APCs, MM plasma cells plausibly expand (n)Tregs and (i)Tregs both through conversion of CD3(+) FoxP3(-) into CD3(+) FoxP3(+) T cells and proliferation of CD3(+) FoxP3(+) T cells, which may suppress the anti-MM immune response.

Dendritic cell maturation in HCV infection: altered regulation of MHC class I antigen processing-presenting machinery.

BACKGROUND & AIMS: Modulation of dendritic cell (DC) function has been theorized as one of the mechanisms used by hepatitis C virus (HCV) to evade the host immune response and cause persistent infection. METHODS: We used a range of cell and molecular biology techniques to study DC subsets from uninfected and HCV-infected individuals. RESULTS: We found that patients with persistent HCV infection have lower numbers of circulating myeloid DC and plasmacytoid DC than healthy controls or patients who spontaneously recovered from HCV infection. Nonetheless, DC from patients with persistent HCV infection display normal phagocytic activity, typical expression of the class I and II HLA and co-stimulatory molecules, and conventional cytokine production when stimulated to mature in vitro. In contrast, they do not display the strong switch from immunoproteasome to standard proteasome subunit expression and the upregulation of the transporter-associated proteins following stimulation, which were instead observed in DC from uninfected individuals. This different modulation of components of the HLA class I antigen processing-presenting machinery results in a differential ability to present a CD8(+) T cell epitope whose generation is dependent on the LMP7 immunoproteasome subunit. CONCLUSIONS: Overall, these findings establish that under conditions of persistent HCV antigenemia, HLA class I antigen processing and presentation are distinctively regulated during DC maturation.

Adipose failure through adipocyte overload and autoimmunity.

Metabolic syndrome poses a great worldwide threat to the health of the patients. Increased visceral adiposity is recognized as the main determinant of the detrimental clinical effects of insulin resistance. Inflammation and immune system activation in the adipose tissue (AT) have a central role in the pathophysiology of metabolic syndrome, but the mechanisms linking increased adiposity to immunity in the AT remain in part elusive. In this review, we support the central role of adipocyte overload and relative adipose failure as key determinants in triggering immune aggression to AT. This provides a mechanistic explanation of the relative metabolic wellness of metabolically normal obese people and the disruption in insulin signaling in metabolically obese lean people.

Classic pyoderma gangrenosum.

Pyoderma gangrenosum is a rare inflammatory ulcerative skin disease of unknown etiology. We report an image of a patient with pyoderma gangrenosum who presented right leg ulcers with violaceous margins, histologically characterized by mono- and polynuclear cell infiltrates. The patient was successfully treated with cyclosporin A.

Endothelial cells in tumor microenvironment: insights and perspectives.

The tumor microenvironment is a highly complex and dynamic mixture of cell types, including tumor, immune and endothelial cells (ECs), soluble factors (cytokines, chemokines, and growth factors), blood vessels and extracellular matrix. Within this complex network, ECs are not only relevant for controlling blood fluidity and permeability, and orchestrating tumor angiogenesis but also for regulating the antitumor immune response. Lining the luminal side of vessels, ECs check the passage of molecules into the tumor compartment, regulate cellular transmigration, and interact with both circulating pathogens and innate and adaptive immune cells. Thus, they represent a first-line defense system that participates in immune responses. Tumor-associated ECs are involved in T cell priming, activation, and proliferation by acting as semi-professional antigen presenting cells. Thus, targeting ECs may assist in improving antitumor immune cell functions. Moreover, tumor-associated ECs contribute to the development at the tumor site of tertiary lymphoid structures, which have recently been associated with enhanced response to immune checkpoint inhibitors (ICI). When compared to normal ECs, tumor-associated ECs are abnormal in terms of phenotype, genetic expression profile, and functions. They are characterized by high proliferative potential and the ability to activate immunosuppressive mechanisms that support tumor progression and metastatic dissemination. A complete phenotypic and functional characterization of tumor-associated ECs could be helpful to clarify their complex role within the tumor microenvironment and to identify EC specific drug targets to improve cancer therapy. The emerging therapeutic strategies based on the combination of anti-angiogenic treatments with immunotherapy strategies, including ICI, CAR T cells and bispecific antibodies aim to impact both ECs and immune cells to block angiogenesis and at the same time to increase recruitment and activation of effector cells within the tumor.

Idiopathic and connective tissue disease-associated pulmonary arterial hypertension (PAH): Similarities, differences and the role of autoimmunity.

Pre-capillary pulmonary arterial hypertension (PAH) is hemodynamically characterized by a mean pulmonary arterial pressure (mPAP) ≥ 20 mmHg, pulmonary capillary wedge pressure (PAWP) ≤15 mmHg and pulmonary vascular resistance (PVR) > 2. PAH is classified in six clinical subgroups, including idiopathic PAH (IPAH) and PAH associated to connective tissue diseases (CTD-PAH), that will be the main object of this review. The aim is to compare these two PAH subgroups in terms of epidemiology, histological and pathogenic findings in an attempt to define disease-specific features, including autoimmunity, that may explain the heterogeneity of response to therapy between IPAH and CTD-PAH.

Immune escape of multiple myeloma cells results from low miR29b and the ensuing epigenetic silencing of proteasome genes.

BACKGROUND: Activation of CD28 on multiple myeloma (MM) plasma cells, by binding to CD80 and CD86 on dendritic cells, decreases proteasome subunit expression in the tumor cells and thereby helps them evade being killed by CD8+ T cells. Understanding how CD28 activation leads to proteasome subunit downregulation is needed to design new MM therapies. METHODS: This study investigates the molecular pathway downstream of CD28 activation, using an in vitro model consisting of myeloma cell lines stimulated with anti-CD28-coated beads. RESULTS: We show that CD28 engagement on U266 and RPMI 8226 cells activates the PI3K/AKT pathway, reduces miR29b expression, increases the expression of DNA methyltransferase 3B (DNMT3B, a target of miR29b), and decreases immunoproteasome subunit expression. In vitro transfection of U266 and RPMI 8226 cells with a miR29b mimic downregulates the PI3K/AKT pathway and DNMT3B expression, restores proteasome subunit levels, and promotes myeloma cell killing by bone marrow CD8+ T cells from MM patients. Freshly purified bone marrow plasma cells (CD138+) from MM patients have lower miR29b and higher DNMT3B (mRNA and protein) than do cells from patients with monoclonal gammopathy of undetermined significance. Finally, in MM patients, high DNMT3B levels associate with shorter overall survival. CONCLUSIONS: Altogether, this study describes a novel molecular pathway in MM. This pathway starts from CD28 expressed on tumor plasma cells and, through the PI3K-miR29b-DNMT3B axis, leads to epigenetic silencing of immunoproteasome subunits, allowing MM plasma cells to elude immunosurveillance. This discovery has implications for the design of innovative miR29b-based therapies for MM.

Lenalidomide arrests cell cycle and modulates PD1-dependent downstream mTOR intracellular signals in melanoma cells.

Despite numerous efforts to define the best therapeutic strategies in advanced melanoma, the response of many patients remains heterogeneous and of short duration. Lenalidomide, an immunomodulating drug, has shown anti-inflammatory, antiangiogenic and anticancer properties in haematological disorders; however, few preclinical data support the rationale for using this drug in melanoma patients. In this study, we investigate lenalidomide's potential role in melanoma by focusing on the in-vitro drug's antiproliferative activity. The antiproliferative action of lenalidomide was evaluated on two melanoma cell lines by MTT assay, cell cycle and apoptosis assay. P21 protein levels were evaluated with droplet digital PCR (ddPCR) and western blot analysis while his interaction with specific cyclin-dependent kinase (CDK) was assessed by immunoprecipitation test. The biological effect and molecular mechanisms of programmed cell death-1 (PD-1) in the regulation of proliferation were evaluated using ddPCR, flow cytometry, western blot and small interfering RNA transfection. We observed that lenalidomide exerts a cytostatic effect in melanoma cell lines by inducing cell cycle arrest in the G0-G1 phase through p21 upregulation and modulation of CDK complexes. Furthermore, we found that lenalidomide has an antiproliferative action through the downregulation of melanoma-PD1 expression and consequently the alteration of intracellular signaling of mammalian target of rapamycin/S6. The present study aims to provide new insights into the role of lenalidomide in melanoma and suggesting to potentially translating these findings into a clinical setting to use immunomodulatory derivatives for blocking the pro-tumorigenic activity of the melanoma through the PD-1/PD-L1 axis.

The emerging role of noncoding RNAs in systemic lupus erythematosus: new insights into the master regulators of disease pathogenesis.

Auto-immune diseases are a form of chronic disorders in which the immune system destroys the body's cells due to a loss of tolerance to self-antigens. Systemic lupus erythematosus (SLE), identified by the production of autoantibodies in different body parts, is one of the most well-known examples of these diseases. Although the etiology of SLE is unclear, the disease's progression may be affected by genetic and environmental factors. As studies in twins provide adequate evidence for genetic involvement in the SLE, other phenomena such as metallization, histone modifications, and alterations in the expression of noncoding RNAs (ncRNAs) also indicate the involvement of epigenetic factors in this disease. Among all the epigenetic alterations, ncRNAs appear to have the most crucial contribution to the pathogenesis of SLE. The ncRNAs' length and size are divided into three main classes: micro RNAs, long noncoding RNAs (LncRNA), and circular RNAs (circRNAs). Accumulating evidence suggests that dysregulations in these ncRNAs contributed to the pathogenesis of SLE. Hence, clarifying the function of these groups of ncRNAs in the pathophysiology of SLE provides a deeper understanding of the disease. It also opens up new opportunities to develop targeted therapies for this disease.

Unraveling the Role of Peroxisome Proliferator-Activated Receptor ß/Δ (PPAR ß/Δ) in Angiogenesis Associated with Multiple Myeloma.

Growing evidence suggests a role for peroxisome proliferator-activated receptor ß/δ (PPAR ß/δ) in the angiogenesis, growth, and metastasis of solid tumors, but little is known about its role in multiple myeloma (MM). Angiogenesis in the bone marrow (BM) is characteristic of disease transition from monoclonal gammopathy of undetermined significance (MGUS) to MM. We examined the expression and function of PPAR ß/δ in endothelial cells (EC) from the BM of MGUS (MGEC) and MM (MMEC) patients and showed that PPAR ß/δ was expressed at higher levels in MMEC than in MGEC and that the overexpression depended on myeloma plasma cells. The interaction between myeloma plasma cells and MMEC promoted the release of the PPAR ß/δ ligand prostaglandin I2 (PGI2) by MMEC, leading to the activation of PPAR ß/δ. We also demonstrated that PPAR ß/δ was a strong stimulator of angiogenesis in vitro and that PPAR ß/δ inhibition by a specific antagonist greatly impaired the angiogenic functions of MMEC. These findings define PGI2-PPAR ß/δ signaling in EC as a potential target of anti-angiogenic therapy. They also sustain the use of PPAR ß/δ inhibitors in association with conventional drugs as a new therapeutic approach in MM.

Cutaneous polyarteritis nodosa and pulmonary arterial hypertension: An unexpected liaison. A case report.

BACKGROUND: Cutaneous polyarteritis nodosa (cPAN) is a form of medium-sized vessel necrotizing vasculitis. It is a rare, skin-limited variant of polyarteritis nodosa, characterized by dermal and subcutaneous tissue involvement. The most common findings in cPAN include digital gangrene, livedo reticularis, and tender subcutaneous nodules. However, while limited to the skin, cPAN results in significant morbidity and mortality due to the accompanying skin ischemia and necrosis, such that patients are vulnerable to superinfection. Here, we describe a unique presentation of cPAN associated with pulmonary arterial hypertension (PAH). METHODS: A 78-year-old female presented with digital ischemia and leg ulcers associated with PAH. Skin biopsy showed necrotizing fibrinoid necrosis of the small- and middle-sized vessels of the dermis. A diagnosis of cPAN and PAH was made. The patient was treated with glucocorticoids, vasodilators, and cyclophosphamide. RESULTS: She died due to severe sepsis complications. CONCLUSION: To date, this is the first case report describing the association between cPAN and PAH. In this case, PAH is a complication of the cutaneous vasculitides suggesting that vasculopathy could play a role in the pathophysiology of PAH. However, the underlying pathophysiological mechanisms still have to be firmly established.

Antiviral effect of SARS-CoV-2 N-specific CD8+ T cells induced in lungs by engineered extracellular vesicles.

Induction of effective immunity in the lungs should be a requisite for any vaccine designed to control the severe pathogenic effects generated by respiratory infectious agents. We recently provided evidence that the generation of endogenous extracellular vesicles (EVs) engineered for the incorporation of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 Nucleocapsid (N) protein induced immunity in the lungs of K18-hACE2 transgenic mice, which then can survive the lethal virus infection. However, nothing is known about the ability of the N-specific CD8+ T cell immunity in controlling viral replication in the lungs, a major pathogenic signature of severe disease in humans. To fill the gap, we investigated the immunity generated in the lungs by N-engineered EVs in terms of induction of N-specific effectors and resident memory CD8+ T lymphocytes before and after virus challenge carried out three weeks and three months after boosting. At the same time points, viral replication extents in the lungs were evaluated. Three weeks after the second immunization, virus replication was reduced in mice best responding to vaccination by more than 3-logs compared to the control group. The impaired viral replication matched with a reduced induction of Spike-specific CD8+ T lymphocytes. The antiviral effect appeared similarly strong when the viral challenge was carried out 3 months after boosting, and associated with the persistence of N-specific CD8+ T-resident memory lymphocytes. In view of the quite low mutation rate of the N protein, the present vaccine strategy has the potential to control the replication of all emerging variants.

Single-cell RNA sequencing uncovers heterogeneous transcriptional signatures in tumor-infiltrated dendritic cells in prostate cancer.

Prostate cancer (PCa) is one of the two solid malignancies in which a higher T cell infiltration in the tumor microenvironment (TME) corresponds with a worse prognosis for the tumor. The inability of T cells to eliminate tumor cells despite an increase in their number reinforces the possibility of impaired antigen presentation. In this study, we investigated the TME at single-cell resolution to understand the molecular function and communication of dendritic cells (DCs) (as professional antigen-presenting cells). According to our data, tumor cells stimulate the migration of immature DCs to the tumor site by inducing inflammatory chemokines. Many signaling pathways such as TNF-α/NF-κB, IL2/STAT5, and E2F up-regulated after DCs enter the tumor location. In addition, some molecules such as GPR34 and SLCO2B1 decreased on the surface of DCs. The analysis of molecular and signaling alterations in DCs revealed some suppression mechanisms of tumors, such as removing mature DCs, reducing the DC's survival, inducing anergy or exhaustion in the effector T cells, and enhancing the differentiation of T cells to Th2 and Tregs. In addition, we investigated the cellular and molecular communication between DCs and macrophages in the tumor site and found three molecular pairs including CCR5/CCL5, CD52/SIGLEC10, and HLA-DPB1/TNFSF13B. These molecular pairs are involved in the migration of immature DCs to the TME and disrupt the antigen-presenting function of DCs. Furthermore, we presented new therapeutic targets by the construction of a gene co-expression network. These data increase our knowledge of the heterogeneity and the role of DCs in PCa TME.