Humans ; Severe Combined Immunodeficiency/therapy*

OBJECTIVE: To report on a child with B-cell-negative severe combined immunodeficiency (B-SCID) manifesting as fulminant myocarditis and carry out genetic testing for her. METHODS: A child with B-SCID who presented at Fujian Maternity and Child Health Care Hospital on January 31, 2021 was selected as the subject. Whole exome sequencing was carried out for her. Candidate variant was verified by Sanger sequencing. RESULTS: The female infant had developed recurrent skin and lung infections soon after birth, and was admitted due to fulminant myocarditis. Serological examination has disclosed a remarkable reduction in immunoglobulins. Flow cytometric analysis revealed that her peripheral blood T and B lymphocytes and NK cells were significantly reduced. Whole exome sequencing revealed that she has harbored a homozygous c.C3007T (p.Q1003X) nonsense variant of the RAG1 gene, for which both of her parents were heterozygous carriers. The variant has not been recorded in normal population databases. Based on the guidelines from the American College of Medical Genetics and Genomics, the variant was predicted to be pathogenic. CONCLUSION A case of RAG1 gene associated B-SCID has been diagnosed. Above finding has enriched the spectrum of RAG1 gene variants and enabled early diagnosis and intervention of the disease.
Female ; Humans ; Pregnancy ; Genetic Testing ; Homeodomain Proteins/genetics* ; Mutation ; Myocarditis/genetics* ; Phenotype ; Severe Combined Immunodeficiency/diagnosis* ; Infant

Common Variable Immunodeficiency/genetics* ; Humans ; Janus Kinase 3/genetics* ; Mutation ; Severe Combined Immunodeficiency

PURPOSE: While there is an urgent need for diagnosis and therapeutic intervention in patients with primary immunodeficiency diseases (PIDs), current genetic tests have drawbacks. We retrospectively reviewed the usefulness of flow cytometry (FCM) as a quick tool for immunophenotyping and functional assays in patients suspected to have PIDs at a single tertiary care institute.METHODS: Between January 2001 and June 2018, patients suspected of having PIDs were subjected to FCM tests, including lymphocyte subset analysis, detection of surface- or intracellular-target proteins, and functional analysis of immune cells, at Samsung Medical Center, Seoul, Korea. The genetic diagnosis was performed using Sanger or diagnostic exome sequencing.RESULTS: Of 60 patients diagnosed with definite or probable PID according to the European Society of Immune Deficiencies criteria, 24 patients were provided with useful information about immunological dysfunction after initial FCM testing. In 10 patients, the PID diagnosis was based on abnormal findings in FCM testing without genetic tests. The FCM findings provided strong evidence for the diagnosis of severe combined immunodeficiency (n = 6), X-linked chronic granulomatous diseases (CGD) (n = 6), leukocyte adhesion deficiency type 1 (n = 3), X-linked agammaglobulinemia (n = 11), autoimmune lymphoproliferative syndrome-FASLG (n = 1), and familial hemophagocytic lymphohistiocytosis type 2 (n = 1), and probable evidence for autosomal recessive-CGD (n = 2), autosomal dominant-hyper-immunoglobulin E (IgE)-syndrome (n = 1), and STAT1 gain-of-function mutation (n = 1). In PIDs derived from PIK3CD (n = 2), LRBA (n = 2), and CTLA4 mutations (n = 3), the FCM test provided useful evidence of immune abnormalities and a tool for treatment monitoring.CONCLUSIONS: The initial application of FCM, particularly with known protein targets on immune cells, would facilitate the timely diagnosis of PIDs and thus would support clinical decisions and improve the clinical outcome.
Agammaglobulinemia ; Diagnosis ; Exome ; Flow Cytometry ; Genetic Testing ; Granulomatous Disease, Chronic ; Humans ; Immunophenotyping ; Korea ; Leukocytes ; Lymphocyte Subsets ; Lymphohistiocytosis, Hemophagocytic ; Phenotype ; Retrospective Studies ; Seoul ; Severe Combined Immunodeficiency ; Tertiary Healthcare

BACKGROUND: Mesenchymal stromal cells (MSCs) have potent immunomodulatory and neuroprotective properties, and have been tested in neurodegenerative diseases resulting in meaningful clinical improvements. Regulatory guidelines specify the need to perform preclinical studies prior any clinical trial, including biodistribution assays and tumourigenesis exclusion. We conducted a preclinical study of human bone marrow MSCs (hBM-MSCs) injected by intrathecal route in Non-Obese Diabetic Severe Combined Immunodeficiency mice, to explore cellular biodistribution and toxicity as a privileged administration method for cell therapy in Friedreich's Ataxia. METHODS: For this purpose, 3 × 10⁵ cells were injected by intrathecal route in 12 animals (experimental group) and the same volume of culture media in 6 animals (control group). Blood samples were collected at 24 h (n = 9) or 4 months (n = 9) to assess toxicity, and nine organs were harvested for histology and safety studies. Genomic DNA was isolated from all tissues, and mouse GAPDH and human β2M and β-actin genes were amplified by qPCR to analyze hBM-MSCs biodistribution. RESULTS: There were no deaths nor acute or chronic toxicity. Hematology, biochemistry and body weight were in the range of normal values in all groups. At 24 h hBM-MSCs were detected in 4/6 spinal cords and 1/6 hearts, and at 4 months in 3/6 hearts and 1/6 brains of transplanted mice. No tumours were found. CONCLUSION: This study demonstrated that intrathecal injection of hBM-MSCs is safe, non toxic and do not produce tumors. These results provide further evidence that hBM-MSCs might be used in a clinical trial in patients with FRDA.
Animals ; Biochemistry ; Body Weight ; Bone Marrow ; Brain ; Cell- and Tissue-Based Therapy ; Culture Media ; DNA ; Friedreich Ataxia ; Heart ; Hematology ; Humans ; Injections, Spinal ; Mesenchymal Stromal Cells ; Methods ; Mice ; Neurodegenerative Diseases ; Neuroprotection ; Reference Values ; Severe Combined Immunodeficiency ; Spinal Cord

Severe combined immunodeficiency disease (SCID) is a group of rare congenital diseases characterized by severe deficiencies in T lymphocyte counts and/or function. The recurrent, persistent and severe infections are its clinical manifestations. Neonatal screening and immune system reconstruction would improve the prognosis of SCID children. Newborn screening programs based on T-cell receptor excision circles (TRECs) quantitative detection have been carried out in clinical practice, however, the methods still have some limitations. Other new methods such as mass spectrometry and T lymphocyte-specific biomarker assays are still under investigation. Hematopoietic stem cell transplantation and gene therapy are the two main methods for reconstructing immune function in SCID children. Through improving the success rate of transplantation and the long-term safety and stability of viral vectors, some achievements have been made by many centers already. However, large-scale prospective studies are needed for evaluation of the long-term efficacy. In this article, the recent progress in newborn screening and immune reconstitution of SCID is reviewed.
Humans ; Immune Reconstitution ; Infant, Newborn ; Neonatal Screening ; trends ; Prospective Studies ; Severe Combined Immunodeficiency ; therapy ; T-Lymphocytes

Recombination activating gene-2 (RAG-2) plays a crucial role in the development of lymphocytes by mediating recombination of T cell receptors and immunoglobulins, and loss of RAG-2 causes severe combined immunodeficiency (SCID) in humans. RAG-2 knockout mice created using homologous recombination in ES cells have served as a valuable immunodeficient platform, but concerns have persisted on the specificity of RAG-2-related phenotypes in these animals due to the limitations associated with the genome engineering method used. To precisely investigate the function of RAG-2, we recently established a new RAG-2 knockout FVB mouse line (RAG-2(−/−)) manifesting lymphopenia by employing a CRISPR/Cas9 system at Center for Mouse Models of Human Disease. In this study, we further characterized their phenotypes focusing on histopathological analysis of lymphoid organs. RAG-2(−/−) mice showed no abnormality in development compared to their WT littermates for 26 weeks. At necropsy, gross examination revealed significantly smaller spleens and thymuses in RAG-2(−/−) mice, while histopathological investigation revealed hypoplastic white pulps with intact red pulps in the spleen, severe atrophy of the thymic cortex and disappearance of follicles in lymph nodes. However, no perceivable change was observed in the bone marrow. Moreover, our analyses showed a specific reduction of lymphocytes with a complete loss of mature T cells and B cells in the lymphoid organs, while natural killer cells and splenic megakaryocytes were increased in RAG-2(−/−) mice. These findings indicate that our RAG-2(−/−) mice show systemic lymphopenia with the relevant histopathological changes in the lymphoid organs, suggesting them as an improved Rag-2-related immunodeficient model.
Animals ; Atrophy ; B-Lymphocytes ; Bone Marrow ; Genome ; Homologous Recombination ; Humans ; Immunoglobulins ; Killer Cells, Natural ; Lymph Nodes ; Lymphocytes ; Lymphopenia* ; Megakaryocytes ; Methods ; Mice* ; Mice, Knockout ; Negotiating ; Phenotype ; Receptors, Antigen, T-Cell ; Recombination, Genetic ; Sensitivity and Specificity ; Severe Combined Immunodeficiency ; Spleen ; T-Lymphocytes ; Thymus Gland

PURPOSE: Severe combined immunodeficiency (SCID) is the most serious form of primary immunodeficiency. Infants with SCID are susceptible to life-threatening infections. To establish newborn screening for SCID in Korea, we performed a screening test for T-cell receptor excision circle (TREC) and κ-deleting recombination excision circle (KREC) in neonates and investigated the awareness of SCID among their parents. METHODS: Collections of dried blood spots from neonates and parent surveys were performed at the Samsung Medical Center and Cheil General Hospital & Women's Healthcare Center in Korea. The amplification crossing point (Cp) value <37.0 was defined as TREC/KRECpositive based on cutoff values from measuring multiplex real-time polymerase chain reaction. A Cp value >39.0 was defined as negative. RESULTS: For TREC/KREC screening, 141 neonates were enrolled; 63 (44.7%) were male. One hundred forty neonates (99.3%) had positive TREC/KREC results at the time of the initial test; 82.3% and 75.9% were positive and 17.0% and 23.4% were weakly positive for TREC and KREC, respectively. In one neonate (0.7%), the initial TREC/KREC test result was negative. However, repeated tests obtained and confirmed a positive result. For an awareness survey, 168 parents were engaged. Only 2% of parents (3/168) knew that the newborn screening test for SCID had been introduced and performed in other countries. Eighty-four percent of parents (141/168) replied that nationwide newborn SCID screening should be performed in Korean newborns. CONCLUSIONS: In this study, newborn SCID screening was performed along with assessment of public awareness of the SCID test in Korea. The study results showed that newborn SCID screening can be readily applied for clinical use at a relatively low cost in Korea.
Delivery of Health Care ; Hospitals, General ; Humans ; Infant ; Infant, Newborn* ; Korea* ; Male ; Mass Screening* ; Neonatal Screening ; Parents ; Pilot Projects* ; Real-Time Polymerase Chain Reaction ; Receptors, Antigen, T-Cell* ; Recombination, Genetic* ; Severe Combined Immunodeficiency* ; Surveys and Questionnaires ; T-Lymphocytes*

During the past decades, there has been a great evolution in the field of fetal therapy for congenital defects. Prenatal screening or diagnostic methods including non-invasive and invasive methods and fetal ultrasound have led to earlier and more accurate diagnosis of congenital anomalies. Recent advances in several therapeutic techniques including ultrasound-guided needle therapy, laser therapy or fetal endoscopy, have allowed some fetuses at risk with anatomical defects, to be corrected in utero but still, its clinical indications remain limited. Over the last 30 years, many researchers found usefulness of pluripotent stem cells from amniotic fluid and placenta because they are sources of diverse progenitor cell populations called mesenchymal stem cells. In some human conditions like severe combined immunodeficiency syndrome and chronic granulomatous disease, fetal therapy using stem cell replacement showed some promising results in researches but more studies are required to apply in clinical settings. The aim of this article is to summarize a current status and future perspective of stem cell therapy for treatment of congenital fetal anomalies.
Amniotic Fluid ; Congenital Abnormalities ; Diagnosis ; Endoscopy ; Female ; Fetal Therapies* ; Fetus ; Granulomatous Disease, Chronic ; Humans ; Laser Therapy ; Mesenchymal Stromal Cells ; Needles ; Placenta ; Pluripotent Stem Cells ; Prenatal Diagnosis ; Severe Combined Immunodeficiency ; Stem Cells* ; Ultrasonography

PURPOSE: Pneumocystis jirovecii pneumonia occurs in various immunocompromised patients. Despite the prophylaxis strategies in clinical practice, certain patients develop P. jirovecii pneumonia. This study was performed to investigate pediatric cases with P. jirovecii pneumonia in a single center. METHODS: We identified pediatric patients younger than 19 years with microbiologically confirmed P. jirovecii pneumonia from January 2000 to February 2014. A retrospective chart review was performed. RESULTS: Fifteen episodes of P. jirovecii pneumonia in 14 patients were identified with median age of 8.3 years (range, 0.4-18.6 years). Among these patients, 11 patients had hematology-oncology diseases, 2 had primary immunodeficiency disorders (one with severe combined immunodeficiency and the other with Wiskott Aldrich syndrome), 1 had systemic lupus erythematosus and 1 received kidney transplant. Four patients were transplant recipients; 1 allogeneic and 2 autologous hematopoietic cell transplant and 1 with kidney transplant. The median absolute lymphocyte count at the diagnosis of P. jirovecii pneumonia was 5,156 cells/mm³ (range, 20-5,111 cells/mm³). In 13 episodes (13 of 15, 86.7%), patients were not receiving prophylaxis at the onset of P. jirovecii pneumonia. For treatment, trimethoprim/sulfamethoxazole was given as a main therapeutic agent in all 15 episodes. Steroid was given in 9 episodes (60%). Median treatment duration was 15 days (range, 4-33 days). Overall mortality at 60 days was 35.7% (5 of 14). CONCLUSION: Majority of our patients developed P. jirovecii pneumonia while not on prophylaxis. Continuous efforts and more data are needed to identify high risk patients who may get benefit from P. jirovecii pneumonia prophylaxis.
Diagnosis ; Humans ; Immunocompromised Host ; Kidney ; Lupus Erythematosus, Systemic ; Lymphocyte Count ; Mortality ; Pediatrics ; Pneumocystis carinii ; Pneumocystis jirovecii* ; Pneumocystis* ; Pneumonia* ; Retrospective Studies ; Severe Combined Immunodeficiency ; Transplant Recipients ; Transplants