Introduction: Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease that is associated with significant morbidity and mortality. SLE disproportionately affects women and minorities. Childhood-onset SLE (cSLE) in particular tends to be more aggressive than adult-onset SLE. Despite substantial improvements in the treatment of cSLE, there is significant variability in treatment responses and long-term outcomes. Furthermore, there is a paucity of studies involving cSLE, and in particular, cSLE among different age groups. The aim of this study was to test the hypothesis that an early-onset cSLE cohort would demonstrate unique characteristics with distinctive clinical and laboratory features at disease onset. We specifically investigated whether clinical, epidemiological, or serological factors are differentially associated with early- and late-onset cSLE. This could have direct impact on clinical management with the goal of improving outcomes and quality of life for children with SLE. Methods: Our study was conducted at a large tertiary center. We included 213 subjects seen at our pediatric rheumatology clinic aged 4–17 years. Epidemiologic, clinical phenotype, disease severity, serology, treatment, and outcome data were compared between subjects with cSLE onset prior to 10 years of age (early-onset disease, n = 43) and those with cSLE onset greater than 10 years of age (peri-adolescent disease, n = 170). We compared clinical features between early- and peri-adolescent onset cSLE in order to investigate the association between age at disease onset of cSLE and clinical disease expression and outcomes. Results: Of the 213 subjects with cSLE in our study, 43 subjects had early-onset disease (age 2 to ≤9 years) and 170 patients had peri-adolescent onset disease. We found that early-onset cSLE was associated with a higher prevalence of positive anti-dsDNA antibody at cSLE diagnosis, higher anti-dsDNA antibody titer at cSLE diagnosis, rash, and azathioprine use (p < 0.001, p = 0.004, p = 0.011, and p = 0.008, respectively). In contrast, we found that peri-adolescent onset cSLE (≥10 years of age) was associated with worse disease activity (SLEDAI range 0–24) (p < 0.001), higher SLICC at diagnosis (p < 0.001), as well as a higher rate of mycophenolate mofetil and hydroxychloroquine use (p = 0.003 and p < 0.001, respectively). There were no significant differences in the prevalence of neuropsychiatric symptoms or the development of Class IV/Class V lupus nephritis between the early-onset and peri-adolescent groups.
Data are limited regarding the immune status of CD40 ligand (CD40L)-deficient carriers and hematopoietic stem cell transplantation (HSCT) outcomes using them as donors for CD40L-deficient patients. Therefore, we studied the immune profiles of 7 carriers, 4 of whom were HSCT donors for family members with CD40L deficiency, and we characterized their HSCT outcomes. Immunoglobulin profiles, CD4, CD8, circulating T-follicular helper (cTfh) cells, and regulatory T cells (Tregs) in carriers were comparable to those in healthy controls. CD40L expression in carriers ranged from 37% to 78%. cTfh cells from carriers expressed higher CD40L compared with total CD4 cells or the memory CD4 compartment, suggesting a potential advantage to CD40L-expressing cTfh cells. Tregs had minimal CD40L expression in carriers and healthy controls. So we postulated that HSCT using donors who were CD40L carriers may result in excellent immune reconstitution without immune dysregulation. Four CD40L-deficient patients underwent HSCT from carriers who had CD40L expression from 37% to 63%. All patients engrafted, achieved excellent immune reconstitution with lack of opportunistic infections, graft-versus-host disease, and immune dysregulation; stable CD40L expression mimicked that of donors 1 to 5 years after HSCT. Immunoglobulin independence was achieved in 3 of the 4 patients. We demonstrated higher CD40L expression in the cTfh compartment of carriers and excellent immune reconstitution using donors who were CD40L carriers in CD40L-deficient patients.
A paucity of effector T cells within tumors renders pancreatic ductal adenocarcinoma (PDAC) resistant to immune checkpoint therapies. While several under-development approaches target immune-suppressive cells in the tumor microenvironment, there is less focus on improving T cell function. Here we show that inhibiting vasoactive intestinal peptide receptor (VIP-R) signaling enhances anti-tumor immunity in murine PDAC models. In silico data mining and immunohistochemistry analysis of primary tumors indicate overexpression of the neuropeptide vasoactive intestinal peptide (VIP) in human PDAC tumors. Elevated VIP levels are also present in PDAC patient plasma and supernatants of cultured PDAC cells. Furthermore, T cells up-regulate VIP receptors after activation, identifying the VIP signaling pathway as a potential target to enhance T cell function. In mouse PDAC models, VIP-R antagonist peptides synergize with anti-PD-1 antibody treatment in improving T cell recruitment into the tumors, activation of tumor-antigen-specific T cells, and inhibition of T cell exhaustion. In contrast to the limited single-agent activity of anti-PD1 antibodies or VIP-R antagonist peptides, combining both therapies eliminate tumors in up to 40% of animals. Furthermore, tumor-free mice resist tumor re-challenge, indicating anti-cancer immunological memory generation. VIP-R signaling thus represents a tumor-protective immune-modulatory pathway that is targetable in PDAC.
Background: Pediatric acute liver failure (PALF) remains an enigmatic process of rapid end-organ dysfunction associated with a variety of pathologic conditions though the predominant cause is indeterminate. A growing body of research has identified mutations in the NBAS gene to be associated with recurrent acute liver failure and multi-systemic disease including short stature, skeletal dysplasia, facial dysmorphism, immunologic abnormalities, and Pelger-Huët anomaly. Methods and Results: Here, we describe a 4-year-old girl who presented with dehydration in the setting of acute gastroenteritis and fever but went on to develop PALF on day 2 of hospitalization. She clinically recovered with supportive measures, but after discharge, had at least 2 additional episodes of PALF. Ultimately, she underwent liver transplant and her recurrent episodes of PALF did not recur throughout a 6-year follow-up period. Whole-exome sequencing post-liver transplant initially revealed two variants of uncertain significance in the NBAS gene. Parental studies confirmed the c.1549C > T(p.R517C; now likely pathogenic) variant from her mother and a novel c.4646T > C(p.L1549P) variant from her father. In silico analyses predicted these variants to have a deleterious effect on protein function. Consistent with previously characterized NBAS mutation-associated disease (NMAD), our patient demonstrated the following features: progeroid facial features, hypoplasia of the 12th ribs, Pelger-Huët anomaly on peripheral blood smear, and abnormal B and NK cell function. Conclusion: Altogether, we describe a novel pathogenic variant in the NBAS gene of a patient with NMAD and report the resolution of recurrent PALF secondary to NMAD following liver transplantation.
A 4-year-old boy presented with perianal abscess and granulomatous colitis, which led the diagnosis of Crohn's disease. He became refractory to all available therapies and required colectomy. Targeted sequencing revealed a deleterious variant in NCF4, causing severe neutrophil dysfunction. He underwent hematopoietic stem cell transplantation (HSCT) with an excellent outcome.
The clinical utility of monitoring immune reconstitution after allotransplant was evaluated using data from Blood and Marrow Transplant Clinical Trials Network BMT CTN 0201 (NCT00075816), a multicenter randomized study of unrelated donor bone marrow (BM) vs granulocyte colony-stimulating factor (G-CSF)-mobilized blood stem cell (G-PB) grafts. Among 410 patients with posttransplant flow cytometry measurements of immune cell subsets, recipients of G-PB grafts had faster T-cell reconstitution than BM recipients, including more naive CD4+ T cells and T-cell receptor excision circle-positive CD41 and CD8+ T cells at 3 months, consistent with better thymic function. Faster reconstitution of CD4+ T cells and naive CD4+ T cells at 1 month and CD8+ T cells at 3 months predicted more chronic graft-versus-host disease (GVHD) but better survival in G-PB recipients, but consistent associations of T-cell amounts with GVHD or survival were not seen in BM recipients. In contrast, a higher number of classical dendritic cells (cDCs) in blood samples at 3 months predicted better survival in BM recipients. Functional T-cell immunity measured in vitro by cytokine secretion in response to stimulation with cytomegalovirus peptides was similar when comparing blood samples from BM and G-PB recipients, but the degree to which acute GVHD suppressed immune reconstitution varied according to graft source. BM, but not G-PB, recipients with a history of grades 2-4 acute GVHD had lower numbers of B cells, plasmacytoid dendritic cells, and cDCs at 3 months. Thus, early measurements of T-cell reconstitution are predictive cellular biomarkers for long-term survival and response to GVHD therapy in G-PB recipients, whereas more robust DC reconstitution predicted better survival in BM recipients.
The United States has experienced a shortage of immunoglobulin since late 2018. Both intravenous immunoglobulin (IVIG) and subcutaneous immunoglobulin (SCIG), which originate from a common plasma pool, have been affected. In August 2019, the U.S. Food and Drug Administration (FDA) confirmed the critical nature of the shortage and its impact on patient care.1 Initially the FDA named two manufacturers, Bio Products Laboratory and Baxalta, who could not meet high demands that exceeded manufacturing plans and available inventory.2 An update from the American Society of Hospital Pharmacists in February 2020 stated that 6 of 7 manufacturers could not meet demands; this impacts 9 of 12 commercially available IVIG products and 7 of 8 SCIG products.3 Together this comprises ~90% of the market share of immunoglobulin.4 While the immunoglobulin shortage in 1998 was attributed to a combination of increased demand, manufacturing challenges, and product recalls over a concern for Creutzfeldt-Jakob disease transmission,5 there is no specific attribution for the current shortage. Drivers of increased demand are likely multifactorial (Figure 1). Though adult patients utilize the majority of immunoglobulin products, IVIG and SCIG play a critical role in immunomodulation and immunoglobulin replacement in pediatrics. The half-life of IVIG is generally accepted to be 3–4 weeks, but can vary based on individual pharmacokinetics.6 Dosing for immunomodulation and replacement of secondary hypogammaglobulinemia varies by disease. Additionally, as immunoglobulin G (IgG) norms fluctuate during early childhood and into adulthood, the ideal threshold level for replacement of secondary hypogammaglobulinemia remains elusive.
Despite increased use of whole exome sequencing (WES) for the clinical analysis of rare disease, overall diagnostic yield for most disorders hovers around 30%. Previous studies of mRNA have succeeded in increasing diagnoses for clearly defined disorders of monogenic inheritance. We asked if targeted RNA sequencing could provide similar benefits for primary immunodeficiencies (PIDs) and very early-onset inflammatory bowel disease (VEOIBD), both of which are difficult to diagnose due to high heterogeneity and variable severity. We performed targeted RNA sequencing of a panel of 260 immune-related genes for a cohort of 13 patients (seven suspected PID cases and six VEOIBD) and analyzed variants, splicing, and exon usage. Exonic variants were identified in seven cases, some of which had been previously prioritized by exome sequencing. For four cases, allele specific expression or lack thereof provided additional insights into possible disease mechanisms. In addition, we identified five instances of aberrant splicing associated with four variants. Three of these variants had been previously classified as benign in ClinVar based on population frequency. Digenic or oligogenic inheritance is suggested for at least two patients. In addition to validating the use of targeted RNA sequencing, our results show that rare disease research will benefit from incorporating contributing genetic factors into the diagnostic approach.
Hematopoietic stem and progenitor cell (HSPC) lentiviral gene therapy is a promising strategy toward a lifelong cure for hemophilia A (HA). The primary risks associated with this approach center on the requirement for pre-transplantation conditioning necessary to make space for, and provide immune suppression against, stem cells and blood coagulation factor VIII, respectively. Traditional conditioning agents utilize genotoxic mechanisms of action, such as DNA alkylation, that increase risk of sterility, infection, and developing secondary malignancies. In the current study, we describe a non-genotoxic conditioning protocol using an immunotoxin targeting CD117 (c-kit) to achieve endogenous hematopoietic stem cell depletion and a cocktail of monoclonal antibodies to provide transient immune suppression against the transgene product in a murine HA gene therapy model. This strategy provides high-level engraftment of hematopoietic stem cells genetically modified ex vivo using recombinant lentiviral vector (LV) encoding a bioengineered high-expression factor VIII variant, termed ET3. Factor VIII procoagulant activity levels were durably elevated into the normal range and phenotypic correction achieved. Furthermore, no immunological rejection or development of anti-ET3 immunity was observed. These preclinical data support clinical translation of non-genotoxic antibody-based conditioning in HSPC LV gene therapy for HA.