Journal of Clinical Immunology最新文献

Fungal infections contribute to a significant disease burden in patients with chronic granulomatous disease (CGD). While the presentation may differ depending on genotype and environmental exposure to fungus, associated mortality rates are universally high. This is a retrospective study wherein medical records of patients diagnosed with CGD from 1994 to 2022 at our center in North India were reviewed. We categorized patients into 2 groups: patients with proven invasive fungal infection and patients with probable invasive fungal infections. We analyzed demographic details, clinical details, and the overall outcome of these patients. We identified 40 patients (40.4%) with fungal infections in our cohort of 99 patients with CGD. Twenty-one patients had proven invasive fungal infection, and 19 had probable invasive fungal infection. Pneumonia was the most common presentation in our cohort (n = 35; 87.5%). Two patients had isolated osteomyelitis, 1 had brain abscess, and 2 had candidemia. Aspergillus sp. was isolated most frequently (n = 27), followed by Candida sp. (n = 5), Mucorales sp. (n = 2), Paecilomyces sp. (n = 1) and Fusarium dimerum (n = 1). Aspergillus fumigatus (n = 11) was the most identified species of Aspergillus. Eleven patients had bacterial co-infection. Twenty-one patients (52.5%) died in this cohort. Risk factors for mortality identified are X-linked CGD (p = 0.027), bacterial coinfection (p = 0.003) and infection in infancy (p = 0.045). Aspergillus sp. is the most common offending fungus, and pneumonia is the most common manifestation of fungal infection in our patients with CGD. Infants, males, and patients with bacterial coinfection should be treated more aggressively amongst patients with CGD with fungal infection.

Background: Non-Aspergillus invasive fungal infections (NAFI) are increasingly reported in patients with Chronic Granulomatous Disease (CGD), but precise clinical descriptions remain scarce.

Objective and methods: We conducted a retrospective analysis of NAFI cases among CGD patients in the French National Registry of Primary Immunodeficiencies (CEREDIH) and in a comprehensive literature review.

Results: We identified 16 proven NAFI (9 molds, 6 yeasts and 1 Pneumocystis) among 263 CGD patients from CEREDIH and included an additional 106 probable/proven NAFI from a literature review (75 molds, 29 yeasts, 1 Pneumocystis, 1 dimorphic). Mold NAFI occurred at a median age of 17 years [IQR 9-23], and were mostly located to the lungs (79%, 65/82). Mold NAFI were breakthrough in 59% of patients (35/59), and 24% were receiving immunosuppressive treatments (13/54, mostly high-dose corticosteroids, n = 11). Lung surgical biopsies yielded the highest diagnostic rate (39/39) compared to less invasive methods (BAL 8/18 and transthoracic punctures 8/12). Nine patients with mold NAFI, including 3 refractory cases, were cured after Hematopoietic Stem Cell Transplantation (HSCT). Overall mortality for mold NAFI was 25% (20/81). Yeast infections occurred at a median age of 5 years [IQR 0-13], and 36% were receiving immunosuppressive treatments (5/14, mostly anti-TNF agents, n = 4). Infections were frequently located to lymph nodes or lungs, and 64% (21/33) were disseminated. Two yeast NAFI were cured after HSCT. Mortality was 26% (7/27).

Conclusion: NAFI in CGD patients are frequently severe, often occur despite prophylaxis and under additional immunosuppression, commonly require invasive procedures for diagnosis, and may be effectively managed with HSCT.

Purpose: Bone marrow failure (BMF) in idiopathic aplastic anemia (AA) and hypoplastic myelodysplastic neoplasms (MDS-h) results from the destruction of hematopoietic progenitors by autoreactive T cells; however, the molecular events driving the pathogenesis of these disorders remain unclear. We therefore applied whole-exome sequencing (WES) in AA and MDS-h patients to identify acquired and inherited gene variants presumed to have functional consequences for BMF. We also used transcriptome profiling to investigate the molecular mechanisms underlying the aberrant T cell response.

Methods: WES was performed on DNA from 42 patients at diagnosis. Transcriptome profiling of CD3⁺ cells was conducted in 21 patients and 10 healthy donors. Peripheral blood cell populations were analyzed by flow cytometry.

Results: Pathogenic/likely pathogenic (P/LP) somatic gene variants were detected in 79% of patients and were functionally associated with BMF-relevant processes such as antigen processing/presentation, T cell-mediated immunity, and DNA repair. P/LP germline gene variants were found in all patients, almost half of whom harbored variants associated with inborn errors of immunity. Patient T cells displayed expression signatures of increased inflammation, apoptosis, hypoxia response, and decreased oxidative phosphorylation. Dysregulated long noncoding RNAs were predicted to primarily regulate the differentiation of T helper 17 cells. Patients also showed significantly lower frequencies of immature progenitors and natural killer cells compared with controls.

Conclusion: Patients with idiopathic AA and MDS-h carried multiple germline immune-related gene variants that may increase susceptibility to immune-mediated BMF. Furthermore, patient T cells exhibited altered energy metabolism, which may represent a therapeutic target for modulating immune responses in autoimmune diseases.

The cellular basis of COVID-19 severity in patients with deficiencies in type I IFN immunity remains unclear. In this study, we differentiated cardiomyocytes and macrophages from IFNAR1 competent (IFNAR1^comp) and deficient (IFNAR1^def) induced pluripotent stem cells (iPSCs), and analyzed virus replication and cytokine production after exposure to SARS-CoV-2. Cardiomyocytes expressed the SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE2) and showed abundant SARS-CoV-2 replication, which was higher in IFNAR1^def than IFNAR1^comp cells. Treatment with exogenous IFNα mitigated infection in IFNAR1^comp, but not in IFNAR1^def cardiomyocytes. In contrast, macrophages did not express ACE2 and did not support SARS-CoV-2 replication, but produced pro-inflammatory cytokines upon virus exposure, which was impaired in IFNAR1^def macrophages. In conclusion, type I IFNs decrease SARS-CoV-2 replication in human iPSC-derived cardiomyocytes, while they increase cytokine responses of macrophages.

Background: Immune dysregulation, polyendocrinopathy, enteropathy, and X-linked(IPEX) syndrome caused by FOXP3 mutations is rare. FOXP3 is a transcription factor required for the regulatory T cell (Treg) development/function.

Aim: We aimed to characterize the clinical, immunologic, and genetic features of a single-center cohort of IPEX syndrome.

Patients and methods: We present the clinical/immunological/genetic features of 12 patients with IPEX syndrome. We used whole exome and Sanger sequencing for the diagnosis/familial segregation. We performed immunophenotyping and measured Treg percentage and FOXP3 expression in peripheral blood by flow cytometric analysis.

Results: Median age at diagnosis was 2.5 years (range: 0.3-22 years). Common clinical manifestations were infections (n = 9, 75%), allergies (n = 8, 67%), autoimmunity (n = 7, 58%), enteropathy (n = 7, 58%), and lymphoproliferation (n = 3, 25%). Atypical initial presentations included class IV lupus nephritis, a SCID-like immunophenotype (CD3⁺ T cells: 4% [100/µL]; CD4⁺ T cells: 3%, CD8⁺ T cells: 1%, CD19⁺ B cells: 81%, CD16/56⁺ NK cells: 13%), and isolated hypogammaglobulinemia persisting for years during follow-up. At the time of diagnosis, three (25%) patients had leukopenia, six (50%) had lymphopenia and two (17%) had neutropenia. Eosinophilia was observed in 42% of patients (25% mild, 17% moderate). Six different variants in FOXP3 were characterized in 12 patients from nine unrelated families. Four (33%) patients underwent hematopoietic stem cell transplantation (HSCT). Overall, three (25%) patients died due to infections. One patient died due to HSCT-related catheter complications, one patient died in an accident. Among the transplanted patients, two are alive and well. Among the non-transplanted patients, five are alive and are being followed up at our center. Treg (CD4⁺CD127^-/lowCD25⁺Foxp3⁺) percentage was low in eight patients compared to healthy controls (p < 0.001). FOXP3 expression was low in all the patients compared to healthy controls.

Conclusion: Atypical presentations make the diagnosis of IPEX syndrome challenging. This study expands the current knowledge of IPEX syndrome by describing a single-center cohort with certain atypical manifestations and by confirming previously reported rare phenotypes. Elucidating the genetic basis of immunodeficiency diseases contributes to improving diagnostic approaches and patient management.

Background: Inborn errors of immunity (IEI) affecting B-cell receptor signaling cause predominantly antibody deficiency (PAD) with varying degrees of severity. Recently, four heterozygous variants in SYK were reported to cause hypogammaglobulinemia, multiorgan inflammatory disease and diffuse large B-cell lymphoma.

Objective: We aimed to unravel the genetic and functional cause of PAD in a 43-year-old female presenting with hypogammaglobulinemia, congenital heart disease and pulmonary hypertension requiring lung transplantation.

Methods: Patient gDNA was subjected to whole-exome and Sanger sequencing. Blood B- and T-cell subsets, as well as tonic and antigen-receptor induced expression levels of phosphorylated-SYK, phosphorylated-ribosomal S6 and phosphorylated p38 were evaluated by flow cytometry.

Results: A novel heterozygous missense SYK variant was identified, mutating a residue in the protein kinase domain (c.1769G > A; p.R590Q), which is highly conserved across vertebrates. While total B- and T-cell numbers were within the normal range, the patient had reduced unswitched and class-switched memory B-cell numbers. Resting B cells from the patient demonstrated enhanced autophosphorylation of SYK, and tonic and ligand-induced phospho-S6 levels. Spontaneous SYK autophosphorylation, S6 and p38 phosphorylation were recapitulated in a pre-clinical cell model, i.e. expression of the SYK R590Q variant in HEK293T cells.

Conclusions: We identified a novel gain-of-function variant in SYK to underlie hypogammaglobulinemia and atypical autoinflammatory disease. Flowcytometric screening for phospho-S6 in lymphocytes of IEI patients can guide genetic diagnosis of B-cell signaling abnormalities.

Background: Primary immunodeficiency disease (PID)/Inborn Errors of Immunity (IEI) with T-cell dysfunction is well-known for susceptibility to opportunistic/viral infections. Epstein-Barr virus-positive smooth muscle tumor (EBV-SMT) is a rare entity primarily seen in the setting of immunodeficiency, such as transplantation, HIV/AIDS, and IEI.

Aim: This study aimed to characterize patients' clinical/immunologic/genetic features with EBV-SMT and assess their association with IEI.

Methods: We reviewed the medical records of patients with EBV-SMT in an outpatient immunology clinic and analyzed a total of 33 patients, including 24 identified from the literature.

Results: The study included nine patients (male/ female = 6/3). The median ages at the onset of symptoms, clinical diagnosis of PID, genetic diagnosis, and EBV-SMT diagnosis were 12 months (1-84 months), 6 years (2-15 years), 10 years (6-18 years), and 10 years (4-18 years), respectively. The parental consanguinity ratio was 7/9(78%). Four patients had combined immunodeficiency. Five out of nine patients (56%) received a genetic IEI diagnosis: JAK3 deficiency (n = 1), STAT1 GOF (n = 1), CARMIL2 deficiency (n = 1), DOCK8 deficiency (n = 1), and ITK deficiency (n = 1). Recurrent infections (100%), chronic diarrhea/colitis (78%), organomegaly (67%), and lymphadenopathy (56%) were prevalent among the patients. Six patients exhibited leiomyoma-like morphology, while three had leiomyosarcoma-like morphology. Five out of nine patients (55%) died, two of whom succumbed due to the complications of hematopoietic stem cell transplantation.

Conclusion: EBV-SMT may suggest an underlying immunodeficiency. Since the mortality is high, early genetic diagnosis of IEI, monitoring the patients with IEI for chronic EBV and cancer, and an individualized therapeutic approach will minimize complications.