Immunologic Research最新文献

Amphotericin B, a polyene macrolide antifungal agent, still plays an important role in the management of serious systemic fungal infections. Amphotericin B deoxycholate (AmBd) has been used to treat invasive fungal infections for over 60 years and remains the primary clinical formulation currently available. Anaphylactoid reactions triggered by AmBd in the clinic have been documented. However, the molecular and cellular events contributing to these reactions have not been clearly elucidated to date. This study demonstrates that the human Mas-related G protein-coupled receptor X2 (MRGPRX2) is the receptor that mediates these anaphylactoid responses. Molecular docking and cellular thermal shift assay (CETSA) indicate that AmBd exhibits potential affinity with MRGPRX2. In vitro, exposure to AmBd results in significant release of LAD2 mast cell granules and induces intracellular Ca²⁺ mobilization as well as activation of PLC-γ/IP3R and PI3K/AKT signaling pathways. However, these phenomena are reduced in MRGPRX2-knockdown LAD2 cells. In vivo, AmBd triggers paw swelling and a rapid drop in core body temperature in wild-type (WT) mice. However, these reactions are almost absent in MRGPRB2 (the mouse homolog of MRGPRX2) knockout mice (MRGPRB2^MUT, MUT). The above results suggest that AmBd activates PLC-γ/IP3R and PI3K/AKT signaling via MRGPRX2 (in human LAD2 mast cells) or MRGPRB2 (in mice), leading to the release of mast cell granules and subsequent triggering of pseudo-allergic reactions. Taken together, this study clarifies the role of MRGPRX2 in triggering pseudo-allergic reactions to AmBd and suggests that MRGPRX2 could be a potential therapeutic target for controlling these reactions.

In the recent EULAR recommendations, ultrasound examination is now recommended as a first-line imaging test in all patients with suspected giant cell arteritis (GCA) and the axillary arteries should be included in the standard exam. As an alternative to ultrasound evaluation, cranial and extracranial arteries can be examined using FDG-PET or MRI. The aim of our study was to observe in a retrospective case series whether there is a correlation between biomarkers and imaging activity in a population of patients followed in real life with GCA treated with prednisone (PDN) and tocilizumab (TCZ). We retrospectively enrolled 68 patients with newly diagnosed GCA between January 2020 and September 2021, followed in real life, who were examined at the Rheumatology Unit of the San Giovanni di Dio Hospital, Florence, Italy. Patients were evaluated at T0-T3-T6-T12-T18-T24 for the following blood tests: ESR, CRP, fibrinogen, platelet count, serum amyloid A (SAA), IL-6, and circulating calprotectin (MRP). Ultrasound examination of the temporal arteries and axillary arteries was assessed at T0 within 7 days of starting treatment with high-dose glucocorticoids and subsequently at T3-T6-T12-T18-T24. A scale from 0 to 3 with semi-quantitative tools (SUV max) was assessed at T0-T12-T24. The evaluation of the correlation coefficient between laboratory and imaging variables has shown that SAA and MRP have the most powerful correlation with the PET score (0.523 and 0.64), and MRP also has an excellent correlation coefficient with the Halo score (0.658). The evaluation of the ROC curves shows for a PET score 3 and SAA values higher than 26 mg/L, sensitivity of 81.5% and specificity of 84.1%, and for a PET score 3 and MRP values higher than 2.3 mcg/mL, sensitivity of 100% and specificity of 76.8%. In this study, we demonstrated that SAA and MRP can be useful as promising tools to detect GCA activity. The study demonstrates a good correlation between the two biomarkers and the imaging activity evaluated by the Halo and PET scores.

Persistent activation of polymorphonuclear neutrophils (PMNs) plays a crucial role in the development of sepsis-related acute lung injury (ALI). This study investigated key molecular mechanisms involved in the hyperactivation of PMNs during ALI. A mouse model of sepsis-related ALI was generated by lipopolysaccharide (LPS) injection. RNA sequencing identified myosin light chain kinase (MLCK) as the most significant differentially expressed gene (DEG) between PMNs isolated from model and control mice. Myocardin (MYOCD) and serum response factor (SRF) were two of the DEGs that could promote transcription of MLCK by binding to its promoter. Either knockdown of MLCK, MYOCD, or SRF ameliorated dysfunction and edema in the lungs of LPS-treated mice. Kyoto Encyclopedia of Genes and Genomes enrichment analysis suggested that the DEGs are enriched in a ferroptosis-related signaling pathway. The MLCK, MYOCD, or SRF knockdown increased contents of ROS, MDA, ferritin, and ferrous iron, and reduced levels of GSH and GPX4 in the PMNs. However, the MLCK overexpression restored ferroptosis resistance and activity of the PMNs, resulting in increased lung injury. Collectively, this study demonstrates that MYOCD and SRF-mediated MLCK upregulation is correlated with ferroptosis resistance and hyperactivation of PMNs in sepsis-related ALI.

Good syndrome (GS), a rare acquired immunodeficiency disorder characterized by thymoma and hypogammaglobulinemia, predisposes individuals to recurrent infections. This study reports a case of a 37-year-old male GS with multiple pulmonary infections and reviews relevant literature. The patient, with a history of thymoma resection, experienced multiple hospitalizations due to lung infections and neutropenia. The alveolar lavage fluid was detected by macro-genomic sequencing (NGS) to detect multiple pathogens, and targeted anti-infective and immunity-enhancing treatments led to improved symptoms and normal neutrophil counts. A literature review of 98 case reports from 2000 to 2023 was conducted, summarizing the associated diseases and pathogens in GS patients. Regular immunoglobulin monitoring in thymoma patients is essential for early GS diagnosis. When empirical antimicrobial therapy fails, mNGS for pathogen detection and targeted therapy are crucial, and regular IVIG injections can reduce infection rates in GS patients.

EBV-associated T/NK-cell lymphoproliferative diseases (EBV-T/NK-LPDs) are characterized by the clonal proliferation of EBV-positive ( +) T/NK cells. EBV is typically latent in B cells and the mechanism by which the EBV genome invades T/NK cells remains unknown. Recent studies have demonstrated that exosomes derived from EBV + B cells play a pivotal role in immunosuppressive microenvironment remodeling. Moreover, the existence of an immunosuppressive microenvironment is known to be critical in the development of EBV-T/NK-LPDs. Hence, we hypothesized that exosomes derived from EBV + B cells might promote the development of EBV-T/NK-LPDs by stimulating immune evasion. In this study, we utilized paraffin sections to clarify the STAT3/IL-10/PD-L1-associated immunosuppressive microenvironment in EBV-T/NK-LPDs. Further, we extracted exosomes from BL2009 (EBV + B cell lymphoma) and CA46 (EBV- B cell lymphoma) cell lines to co-culture with cutaneous T-cell lymphoma (CTCL) cell lines, to verify the changes in the above immune evasion pathway. The paraffin sections of EBV-T/NK-LPDs showed high-expression levels of IL-10/PD-L1, which might be related to the phosphorylation of STAT3. Exosomes derived from EBV + B cells could significantly activate the STAT3/IL-10/PD-L1 pathway. After being treated with C188-9, EBV + B cell-derived exosomes were no longer able to stimulate the expression of IL-10/PD-L1 in CTCL cells. EBV-T/NK-LPDs have a STAT3/IL-10/PD-L1 overactivation-associated immunosuppressive microenvironment. Our study elucidated part of this mechanism. Exosomes derived from EBV + B could induce phosphorylation of STAT3 in CTCL cells, leading to the overexpression of IL-10/PD-L1. Our findings might shed light on new directions for understanding immune evasion in EBV-T/NK-LPDs.

Conventional therapeutic agents are no longer adequate against leishmaniasis. This complex condition continues to have a high mortality rate and public health impact. The present study aimed to explore an extensive array of experiments to monitor the biological activities of 6-shogaol, a major component of ginger, and meglumine antimoniate (MA or Glucantime®). The binding affinity of 6-shogaol and inducible nitric oxide synthase (iNOS), a major enzyme catalyzing nitric oxide (NO) from L-arginine was the source for the docking outline. The inhibitory effects of 6-shogaol, MA, and mixture were assessed using colorimetric and macrophage assays. Antioxidant activity was inferred by UV-visible spectrophotometry. Variably expressed genes were measured by quantifiable real-time polymerase chain reaction. Apoptotic and cell cycle profiles were analyzed by flow cytometry. Moreover, a DNA fragmentation assay was performed by electrophoresis and antioxidant metabolites include superoxide dismutase (SOD), catalase (CAT), and also nitric oxide (NO) by enzyme-linked immunosorbent assay. 6-shogaol and MA exhibited multiple synergistic mechanisms of action. These included a remarkable leishmanicidal effect, potent antioxidative activity, a high safety index, upregulation of M1 macrophages/Th1-associated cytokines (including, γ-interferon, interleukin-12p40, tumor necrotizing factor-alpha, and associated iNOS), significant cell division capture at the sub-G0/G1 phase, a high profile of apoptosis through DNA fragmentation of the nuclear components. In addition, the activity of NO was substantially elevated by treated intracellular amastigotes, while SOD and CAT activities were significantly diminished. This study is exclusive because no similar investigation has inclusively been conducted before. These comprehensive mechanistic actions form a logical foundation for additional advanced study.

Major Histocompatibility Complex Class II Deficiency is a rare primary immunodeficiency disease with autosomal recessive inheritance. It is characterized by the absence of Major Histocompatibility Complex Class II molecules on the surface of immune cells. In this article, we will present a four-month-old baby girl who presented with recurrent fever and progressive exacerbation of respiratory symptoms since a month ago. Relevant examinations suggested pancytopenia, a decrease in CD4 and CD3 ratio, and CD4/CD8 inversion, hypogammaglobulinemia, and diagnosis of hemophagocytic syndrome during treatment which all led to the consideration of the presence of immunodeficiency diseases, and the diagnosis of Major Histocompatibility Complex Class II Deficiency was made by peripheral blood whole-exon sequencing (WES). This case is remarkable in that it reveals features of hemophagocytic syndrome in a Major Histocompatibility Complex Class II Deficiency infant, most probably caused by cytomegalovirus, which rarely reported before, and the Major Histocompatibility Complex Class II Deficiency caused by a novel mutation site in the RFXANK gene which never reported, and it also describes the diagnostic and therapeutic course in detail. In addition, we have summarized the information related to Major Histocompatibility Complex Class II Deficiency triggered by mutations in the RFXANK gene to assist clinicians in early recognition and diagnosis.

Dysautonomia is an abnormal clinical state with multiple etiologies, including autoimmunity. Antiphospholipid antibodies (aPL) are among the autoantibodies that have been associated with autonomic dysfunction. We have observed that an elevated total serum IgM appears to be associated with the presence of aPL in dysautonomia patients. This is a retrospective study analyzing the clinical characteristics of 45 consecutive patients with cardiac autonomic dysfunction and a persistently elevated total serum IgM. 93% of patients were female with a mean age of 32.7 years. Most patients had severely disabling disease, with a mean Karnofsky-like functional ability score of 42% (normal 100%). 93% of patients tested persistently positive for one or more aPL and all patients tested persistently positive for aPL and/or Sjogren's antibodies. No patient had lupus specific antibodies. One third of patients experienced one or more thrombotic events and 58% of patients attempting pregnancy experienced pregnancy morbidity. Lastly, 78% of aPL-positive patients treated with antithrombotic therapy experienced 50 to 100% improvement in one or more symptoms (e.g., migraine, cognitive dysfunction) recognized to be responsive to antithrombotic therapy in a subset of aPL-positive patients and 73% of patients treated with and tolerating immune modulatory therapy experienced a positive response. We propose total serum IgM as a reliable and inexpensive test that can be used to identify dysautonomia patients at risk for persistent aPL-positivity. These patients are important to identify as they have a significant risk for thrombosis and pregnancy morbidity and often experience significant symptomatic improvement with antithrombotic therapy and/or immune modulatory therapy.

Single-cell RNA sequencing (scRNA-seq) has contributed to understanding cellular heterogeneity and immune profiling in cancer. The aim of the study was to investigate gene expression and immune profiling in colorectal cancer (CRC) using scRNA-seq. We analyzed single-cell gene expression and T cell receptor (TCR) sequences in 30 pairs of CRC and matched normal tissue. Intratumoral lymphocytes were measured with digital image analysis. CRC had more T cells, epithelial cells, and myeloid cells than normal colorectal tissue. CRCs with microsatellite instability had more abundant T cells than those without microsatellite instability. Immune cell compositions of CRC and normal colorectal tissue were inversely correlated. CD4 + or CD8 + proliferating T cells, CD4 + effector memory T cells, CD8 + naïve T cells, and regulatory T cells of CRC showed higher TCR clonal expansion. Tumor epithelial cells interacted with immune cells more strongly than normal. T cells, myeloid cells, and fibroblasts from CRCs of expanded T cell clonotypes showed increased expression of genes related to TNF and NFKB signaling and T cell activation. CRCs of expanded T cell clonotypes also showed stronger cellular interactions among immune cells, fibroblasts, and endothelial cells. Pro-inflammatory CXCL and TNF signaling were activated in CRCs of expanded T cell clonotype. In conclusion, scRNA-seq analysis revealed different immune cell compositions, differential gene expression, and diverse TCR clonotype dynamics in CRC. TCR clonality expansion is associated with immune activation through T cell signaling and chemokine signaling. Patients with CRCs of expanded clonotype can be promising candidates for immunotherapy.

Artificial intelligence (AI) is increasingly being used in medicine to enhance the speed and accuracy of disease diagnosis and treatment. AI-based image analysis is expected to play a crucial role in future healthcare facilities and laboratories, offering improved precision and cost-effectiveness. As technology advances, the requirement for specialized software knowledge to utilize AI applications is diminishing. Our study will examine the advantages and challenges of employing AI-based image analysis in the field of immunology and will investigate whether physicians without software expertise can use MS Azure Portal for ANA IIF test classification and image analysis. This is the first study to perform Hep-2 image analysis using MS Azure Portal. We will also assess the potential for AI applications to aid physicians in interpreting ANA IIF results in immunology laboratories. The study was designed in four stages by two specialists. Stage 1: creation of an image library, Stage 2: finding an artificial intelligence application, Stage 3: uploading images and training artificial intelligence, Stage 4: performance analysis of the artificial intelligence application. In the first training, the average pattern identification accuracy for 72 testing images was 81.94%. After the second training, this accuracy increased to 87.5%. Patterns Precision improved from 71.42 to 79.96% after the second training. As a result, the number of correctly identified patterns and their accuracy increased with the second training process. Artificial intelligence-based image analysis shows promising potential. This technology is expected to become essential in healthcare facility laboratories, offering higher accuracy rates and lower costs.