Journal of Clinical Immunology最新文献

Background

IL10RA (IL10 receptor subunit alpha) deficiency is an autosomal recessive disease that causes inflammatory bowel disease during early infancy. Its clinical course is often fatal and the only curative treatment is allogeneic hematopoietic cell transplantation (HCT). In Japan, only case reports are available, and there are no comprehensive reports of treatment outcomes.

Methods

We retrospectively analyzed patients with IL10RA deficiency in Japan.

Results

Two newly identified and five previously reported patients were included in this study. Five patients underwent HCT; one untransplanted patient survived to age 14, and one died of influenza encephalopathy before transplantation. All five HCT recipients underwent HCT at the age before 2 years. They all were conditioned with fludarabine/busulfan- or fludarabine /melphalan-based regimens. The donor source was human leukocyte antigen haploidentical donor bone marrow (BM) for two patients and unrelated umbilical cord blood (CB) for two patients. One patient experienced graft failure with unrelated CB and required a second transplant with unrelated BM. All patients who underwent HCT survived and demonstrated an improved performance status.

Conclusion

In cases of IL10RA deficiency, the need for transplantation should be promptly assessed, and early transplantation should be considered. (190/250)

Purpose

Genetic hypomorphic defects in X chromosomal IKBKG coding for the NF-κB essential modulator (NEMO) lead to ectodermal dysplasia and immunodeficiency in males and the skin disorder incontinentia pigmenti (IP) in females, respectively. NF-κB essential modulator (NEMO) Δ-exon 5-autoinflammatory syndrome (NEMO-NDAS) is a systemic autoinflammatory disease caused by alternative splicing and increased proportion of NEMO-Δex5. We investigated a female carrier presenting with IP and NEMO-NDAS due to non-skewed X-inactivation.

Methods

IKBKG transcripts were quantified in peripheral blood mononuclear cells isolated from the patient, her mother, and healthy controls using RT-PCR and nanopore sequencing. Corresponding proteins were analyzed by western blotting and flow cytometry. Besides toll-like receptor (TLR) and tumor necrosis factor (TNF) signaling, the interferon signature, cytokine production and X-inactivation status were investigated.

Results

IP and autoinflammation with recurrent fever, oral ulcers, hepatitis, and neutropenia, but no immunodeficiency was observed in a female patient. Besides moderately reduced NEMO signaling function, type I interferonopathy, and elevated IL-18 and CXCL10 were found. She and her mother both carried the heterozygous variant c.613 C > T p.(Gln205*) in exon 5 of IKBKG previously reported in NEMO-deficient patients. However, X-inactivation was skewed in the mother, but not in the patient. Alternative splicing led to increased ratios of NEMO-Dex5 over full-length protein in peripheral blood cell subsets causing autoinflammation. Clinical symptoms partially resolved under treatment with TNF inhibitors.

Conclusion

Non-skewed X-inactivation can lead to NEMO-NDAS in females with IP carrying hypomorphic IKBKG variants due to alternative splicing and increased proportions of NEMO-∆ex5.

LRBA deficiency is an inborn error of immunity defined by autoimmunity, lymphoproliferation, recurrent infections, cytopenia, and inflammatory bowel disease. Despite recent advances in managing this disease with targeted biologic therapy, haematopoietic stem cell transplant (HSCT) remains the only cure. However, great variability exists between protocols used to transplant patients with LRBA deficiency. We describe a cohort of seven patients with LRBA deficiency who underwent HSCT using a myeloablative, reduced toxicity regime of fludarabine, treosulfan, and thiotepa at two transplantation centres from 2016 to 2019. Data were collected both retrospectively and prospectively, measuring time to engraftment, infectious complications, incidence of graft versus host disease, and post-transplantation chimerism. Six of seven patients survived transplantation, and four of six surviving patients achieving treatment-free survival. We thus recommend that HSCT with fludarabine, treosulfan, and thiotepa-based conditioning be considered in patients with LRBA deficiency.

Objective

To analyze the lymphocyte subsets in individuals with Kabuki syndrome for better characterizing the immunological phenotype of this rare congenital disorder.

Methods

We characterized the immunological profile including B-, T- and natural killer-cell subsets in a series (N = 18) of individuals with Kabuki syndrome.

Results

All 18 individuals underwent genetic analysis: 15 had a variant in KMT2D and 3 a variant in KDM6A. Eleven of the 18 individuals (61%) had recurrent infections and 9 (50%) respiratory infections. Three (17%) had autoimmune diseases. On immunological analysis, 6 (33%) had CD4 T-cell lymphopenia, which was preferentially associated with the KMT2D truncating variant (5/9 individuals). Eight of 18 individuals (44%) had a humoral deficiency and eight (44%) had B lymphopenia. We found abnormal distributions of T-cell subsets, especially a frequent decrease in recent thymic emigrant CD4 + naive T-cell count in 13/16 individuals (81%).

Conclusion

The immunological features of Kabuki syndrome showed variable immune disorders with CD4 + T-cell deficiency in one third of cases, which had not been previously reported. In particular, we found a reduction in recent thymic emigrant naïve CD4 + T-cell count in 13 of 16 individuals, representing a novel finding that had not previously been reported.

High ferritin is an important and sensitive biomarker for the various forms of hemophagocytic lymphohistiocytosis (HLH), a diverse and deadly group of cytokine storm syndromes. Early action to prevent immunopathology in HLH often includes empiric immunomodulation, which can complicate etiologic work-up and prevent collection of early/pre-treatment research samples. To address this, we instituted an alert system at UPMC Children’s Hospital where serum ferritin > 1000 ng/mL triggered real-time chart review, assessment of whether the value reflected “inflammatory hyperferritnemia (IHF)”, and biobanking of remnant samples from consenting IHF patients. We extracted relevant clinical data; periodically measured serum total IL-18, IL-18 binding protein (IL-18BP), and CXCL9; retrospectively classified patients by etiology into infectious, rheumatic, or immune dysregulation; and subjected a subgroup of samples to a 96-analyte biomarker screen. 180 patients were identified, 30.5% of which had IHF. Maximum ferritin levels were significantly higher in patients with IHF than with either hemoglobinopathy or transplant, and highly elevated total IL-18 levels were distinctive to patients with Stills Disease and/or Macrophage Activation Syndrome (MAS). Multi-analyte analysis showed elevation in proteins associated with cytotoxic lymphocytes in all IHF samples when compared to healthy controls and depression of proteins such as ANGPT1 and VEGFR2 in samples from hyperferritinemic sepsis patients relative to non-sepsis controls. This real-time IFH screen proved feasible and efficient, validated prior observations about the specificity of IL-18, enabled early sample collection from a complex population, suggested a unique vascular biomarker signature in hyperferritinemic sepsis, and expanded our understanding of IHF heterogeneity.

Autosomal recessive agammaglobulinemia is a severe primary antibody deficiency disorder typically presenting in infancy. We present a rare case of an 8-year-old boy with AR agammaglobulinemia due to a homozygous splice site variant (c.499-1G > A) in the CD79A gene. Despite monthly intravenous immunoglobulin replacement and prophylactic antibiotics, he developed refractory Helicobacter bilis leg ulcers. Helicobacter species are known for extracellular colonization and are challenging to culture, necessitating molecular diagnostics for identification. The patient required prolonged treatment with intravenous meropenem followed by oral metronidazole and doxycycline for resolution of the ulcers over two years. The patient also exhibited persistent asymptomatic thrombocytopenia, an atypical finding in CD79A mutation cases. This case underscores the importance of genetic diagnosis and targeted antimicrobial therapy in managing rare infections associated with primary immunodeficiencies like autosomal recessive agammaglobulinemia due to CD79A mutation.