Updates in the Understanding of Immunoglobulin Replacement Therapy in Primary Immune Deficiency Disorders: Function, Composition, and Role in Reconstitution and Immunomodulation.

Clinical indications for immunoglobulin therapy can be broadly classified into replacement therapy for immunodeficiencies, immunomodulatory treatment of inflammatory conditions, and hyperimmune therapy against specific infectious agents. When starting immunoglobulin therapy, there are important considerations for the clinician including indication and function, composition, dosing, route, and safety. Immunoglobulin therapy should be tailored to an individual patient.

Clinicopathologic Features and the Spectrum of Myelokathexis in Warts, Hypogammaglobulinemia, Infections, Myelokathexis Syndrome.

Warts, hypogammaglobulinemia, infections, myelokathexis (WHIM) syndrome is a rare primary immunodeficiency disorder predominantly caused by germline CXCR4 variants. Bone marrow (BM) evaluation showing myelokathexis helps to establish the diagnosis of WHIM syndrome, but unfamiliarity with pertinent diagnostic features and variability in morphologic and clinical findings may result in disease underrecognition. We aimed to characterize the clinical, BM, and peripheral blood (PB) features of 30 patients with germline CXCR4 variants, including genotype-phenotype analysis and correlation between morphologic features and functional CXCR4 receptor internalization defect.

Multi-Year Registry Study of Elapegademase Treatment in Patients With Adenosine Deaminase Severe Combined Immunodeficiency (ADA-SCID) Requiring Enzyme Replacement Therapy.

Purpose: The safety and tolerability of elapegademase (elapegademase-lvlr; Revcovi) a PEGylated recombinant adenosine deaminase (ADA), were demonstrated in two Phase 3 clinical trials in the U.S. and Japan in patients with ADA-deficient severe combined immunodeficiency (ADA-SCID).

IKAROS protein stability is regulated by its early N-terminal region and C-terminal dimerization domain.

IKAROS, encoded by IKZF1, is a six zinc-finger (ZF) transcription factor integral to lymphocyte development and function. IKZF1 mutations affecting DNA-binding (ZF1-4) and dimerization (ZF5-6) have been extensively reported and result in human disease. Herein, we investigated IKZF1 mutations affecting protein stability.

Case Report: Aplastic anemia related to a novel variant.

A 20-year-old male patient with a history of celiac disease came to medical attention after developing profound fatigue and pancytopenia. Evaluation demonstrated pan-hypogammaglobulinemia. There was no history of significant clinical infections.

Treatment with Elapegademase Restores Immunity in Infants with Adenosine Deaminase Deficient Severe Combined Immunodeficiency.

Purpose: Patients with adenosine deaminase 1 deficient severe combined immunodeficiency (ADA-SCID) are initially treated with enzyme replacement therapy (ERT) with polyethylene glycol-modified (PEGylated) ADA while awaiting definitive treatment with hematopoietic stem cell transplant (HSCT) or gene therapy. Beginning in 1990, ERT was performed with PEGylated bovine intestinal ADA (ADAGEN®). In 2019, a PEGylated recombinant bovine ADA (Revcovi®) replaced ADAGEN following studies in older patients previously treated with ADAGEN for many years.

Case Report: Profound newborn leukopenia related to a novel RAC2 variant.

We report the case of a 1-week-old male born full-term, who had two inconclusive severe combined immunodeficiency (SCID) newborn screens and developed scalp cellulitis and bacteremia. He did not pass early confirmatory hearing screens. Initial blood counts and lymphocyte flow cytometry revealed profound neutropenia and lymphopenia with a T-/B-/NK- phenotype.

Relevance of lymphocyte proliferation to PHA in severe combined immunodeficiency (SCID) and T cell lymphopenia.

Severe combined immunodeficiency (SCID) is characterized by a severe deficiency in T cell numbers. We analyzed data collected (n = 307) for PHA-based T cell proliferation from the PIDTC SCID protocol 6901, using either a radioactive or flow cytometry method. In comparing the two groups, a smaller number of the patients tested by flow cytometry had <10% of the lower limit of normal proliferation as compared to the radioactive method (p = 0.

Pediatric oral food challenges in the outpatient setting: A single-center experience.

Background: Oral food challenge (OFC) is the criterion standard for diagnosing food allergy (FA). It is important to have parameters to aid in selecting ideal OFC candidates.

Objective: We sought to characterize outcomes and predictors of OFCs for common food allergens.

Posttransplantation late complications increase over time for patients with SCID: A Primary Immune Deficiency Treatment Consortium (PIDTC) landmark study.

Background: The Primary Immune Deficiency Treatment Consortium (PIDTC) enrolled children in the United States and Canada onto a retrospective multicenter natural history study of hematopoietic cell transplantation (HCT).

Objective: We investigated outcomes of HCT for severe combined immunodeficiency (SCID).

Methods: We evaluated the chronic and late effects (CLE) after HCT for SCID in 399 patients transplanted from 1982 to 2012 at 32 PIDTC centers.

Intestinal microbiome and metabolome signatures in patients with chronic granulomatous disease.

Background: Chronic granulomatous disease (CGD) is caused by defects in any 1 of the 6 subunits forming the nicotinamide adenine dinucleotide phosphate oxidase complex 2 (NOX2), leading to severely reduced or absent phagocyte-derived reactive oxygen species production. Almost 50% of patients with CGD have inflammatory bowel disease (CGD-IBD). While conventional IBD therapies can treat CGD-IBD, their benefits must be weighed against the risk of infection.

Team Approach: Metal Hypersensitivity in Total Joint Arthroplasty.

»: As total joint arthroplasty volume continues to grow nationwide, more uncommon complications such as metal implant hypersensitivity are reported with greater frequency in the literature.

»: Metal hypersensitivity is a challenging diagnosis given the potentially vague symptomology. It should be considered a diagnosis of exclusion, necessitating careful consideration of other potential etiologies of a failing implant before arriving at the final diagnosis of metal hypersensitivity.

Monogenic early-onset lymphoproliferation and autoimmunity: Natural history of STAT3 gain-of-function syndrome.

Background: In 2014, germline signal transducer and activator of transcription (STAT) 3 gain-of-function (GOF) mutations were first described to cause a novel multisystem disease of early-onset lymphoproliferation and autoimmunity.

Objective: This pivotal cohort study defines the scope, natural history, treatment, and overall survival of a large global cohort of patients with pathogenic STAT3 GOF variants.

Methods: We identified 191 patients from 33 countries with 72 unique mutations.

Disease Progression of WHIM Syndrome in an International Cohort of 66 Pediatric and Adult Patients.

Warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome (WS) is a combined immunodeficiency caused by gain-of-function mutations in the C-X-C chemokine receptor type 4 (CXCR4) gene. We characterize a unique international cohort of 66 patients, including 57 (86%) cases previously unreported, with variable clinical phenotypes. Of 17 distinct CXCR4 genetic variants within our cohort, 11 were novel pathogenic variants affecting 15 individuals (23%).

Bone marrow transplantation for CVID-like humoral immune deficiency associated with red cell aplasia.

Patients with common variable immunodeficiency (CVID) have a higher incidence of autoimmune disease, which may mark the disease onset; however, anemia secondary to pure red cell aplasia is an uncommon presenting feature. Here, we describe a case of CVID-like humoral immune deficiency in a child who initially presented with red cell aplasia and ultimately developed progressive bone marrow failure. Although bone marrow transplantation (BMT) has been associated with high mortality in CVID, our patient was successfully treated with a matched sibling BMT and engrafted with >98% donor chimerism and the development of normal antibody titers to diphtheria and tetanus toxoids.

Dominant Splice Site Mutations in PIK3R1 Cause Hyper IgM Syndrome, Lymphadenopathy and Short Stature.

The purpose of this research was to use next generation sequencing to identify mutations in patients with primary immunodeficiency diseases whose pathogenic gene mutations had not been identified. Remarkably, four unrelated patients were found by next generation sequencing to have the same heterozygous mutation in an essential donor splice site of PIK3R1 (NM_181523.2:c.

Clinical application of whole-genome sequencing in patients with primary immunodeficiency.

This report illustrates the value of whole genome sequencing (WGS) in elucidating the genetic cause of disease in patients with primary immunodeficiency (PID). As sequencing costs decline, we predict that utilization of next generation sequencing (NGS) in the clinical setting will increase.

A nonsense mutation in IKBKB causes combined immunodeficiency.

Identification of the molecular etiologies of primary immunodeficiencies has led to important insights into the development and function of the immune system. We report here the cause of combined immunodeficiency in 4 patients from 2 different consanguineous Qatari families with similar clinical and immunologic phenotypes. The patients presented at an early age with fungal, viral, and bacterial infections and hypogammaglobulinemia.

CLN5 and CLN8 protein association with ceramide synthase: biochemical and proteomic approaches.

Four patients with juvenile neuronal ceroid lipofuscinoses, a childhood neurodegenerative disorder that was previously described as CLN9 variant, are reclassified as CLN5 disease. CLN5-deficient (CLN5(-/-) ) fibroblasts demonstrate adhesion defects, increased growth, apoptosis, and decreased levels of ceramide, sphingomyelin, and glycosphingolipids. The CLN8 protein (CLN8p) corrects growth and apoptosis in CLN5(-/-) cells.

Future therapies for food allergy.

Food allergy affects 3.9% of US children and is increasing in prevalence. The current standard of care involves avoidance of the triggering food and treatment for accidental ingestions.

Synergistic control of T cell development and tumor suppression by diacylglycerol kinase alpha and zeta.

Diacylglycerol (DAG) kinases (DGKs) are a family of enzymes that convert DAG to phosphatidic acid (PA), the physiologic functions of which have been poorly defined. We report here that DGK alpha and zeta synergistically promote T cell maturation in the thymus. Absence of both DGKalpha and zeta (DGKalpha(-/-)zeta(-/-)) results in a severe decrease in the number of CD4(+)CD8(-) and CD4(-)CD8(+) single-positive thymocytes correlating with increased DAG-mediated signaling.

CLN3p impacts galactosylceramide transport, raft morphology, and lipid content.

Juvenile neuronal ceroid lipofuscinosis (JNCL) belongs to the neuronal ceroid lipofuscinoses characterized by blindness/seizures/motor/cognitive decline and early death. JNCL is caused by CLN3 gene mutations that negatively modulate cell growth/apoptosis. CLN3 protein (CLN3p) localizes to Golgi/Rab4-/Rab11-positive endosomes and lipid rafts, and harbors a galactosylceramide (GalCer) lipid raft-binding domain.