Clinical and Genetic Characteristics of BCG Disease in Chinese Children: a Retrospective Study.

PURPOSE: Summarize the characteristics of a large cohort of BCG disease and compare differences in clinical characteristics and outcomes among different genotypes and between primary immunodeficiency disease (PID) and patients without identified genetic etiology. METHODS: We collected information on patients with BCG disease in our center from January 2015 to December 2020 and divided them into four groups: chronic granulomatous disease (CGD), Mendelian susceptibility to mycobacterial disease (MSMD), severe combined immunodeficiency disease (SCID), and gene negative group. RESULTS: A total of 134 patients were reviewed, and most of them had PID. A total of 111 (82.8%) patients had 18 different types of pathogenic gene mutations, most of whom (91.0%) were classified with CGD, MSMD, and SCID. CYBB was the most common gene mutation (52/111). BCG disease behaves differently in individuals with different PIDs. Significant differences in sex (P < 0.001), age at diagnosis (P = 0.013), frequency of recurrent fever (P = 0.007), and vaccination-homolateral axillary lymph node enlargement (P = 0.039) and infection severity (P = 0.006) were noted among the four groups. The CGD group had the highest rate of males and the oldest age at diagnosis. The MSMD group had the highest probability of disseminated infection (48.3%). The course of anti-tuberculosis treatment and the survival time between patients with PID and without identified genetic etiology were similar. CONCLUSION: Greater than 80% of BCG patients have PID; accordingly, gene sequencing should be performed in patients with BCG disease for early diagnosis. BCG disease behaves differently in patients with different types of PID. Patients without identified genetic etiology had similar outcomes to PID patients, which hints that they may have pathogenic gene mutations that need to be discovered.

DNA-dependent protein kinase inhibition blocks asthma in mice and modulates human endothelial and CD4⁺ T-cell function without causing severe combined immunodeficiency.

BACKGROUND: We reported that DNA-dependent protein kinase (DNA-PK) is critical for the expression of nuclear factor κB-dependent genes in TNF-α-treated glioblastoma cells, suggesting an involvement in inflammatory diseases. OBJECTIVE: We sought to investigate the role of DNA-PK in asthma. METHODS: Cell culture and ovalbumin (OVA)- or house dust mite-based murine asthma models were used in this study. RESULTS: DNA-PK was essential for monocyte adhesion to TNF-α-treated endothelial cells. Administration of the DNA-PK inhibitor NU7441 reduced airway eosinophilia, mucus hypersecretion, airway hyperresponsiveness, and OVA-specific IgE production in mice prechallenged with OVA. Such effects correlated with a marked reduction in lung vascular cell adhesion molecule 1 expression and production of several cytokines, including IL-4, IL-5, IL-13, eotaxin, IL-2, and IL-12 and the chemokines monocyte chemoattractant protein 1 and keratinocyte-derived chemokine, with a negligible effect on IL-10/IFN-γ production. DNA-PK inhibition by gene heterozygosity of the 450-kDa catalytic subunit of the kinase (DNA-PKcs(+/-)) also prevented manifestation of asthma-like traits. These results were confirmed in a chronic model of asthma by using house dust mite, a human allergen. Remarkably, such protection occurred without causing severe combined immunodeficiency. Adoptive transfer of TH2-skewed OT-II wild-type CD4(+) T cells reversed IgE and TH2 cytokine production but not airway hyperresponsiveness in OVA-challenged DNA-PKcs(+/-) mice. DNA-PK inhibition reduced IL-4, IL-5, IL-13, eotaxin, IL-8, and monocyte chemoattractant protein 1 production without affecting IL-2, IL-12, IFN-γ, and interferon-inducible protein 10 production in CD3/CD28-stimulated human CD4(+) T cells, potentially by blocking expression of Gata3. These effects occurred without significant reductions in T-cell proliferation. In mouse CD4(+) T cells in vitro DNA-PK inhibition severely blocked CD3/CD28-induced Gata3 and T-bet expression in CD4(+) T cells and prevented differentiation of TH1 and TH2 cells under respective TH1- and TH2-skewing conditions. CONCLUSION: Our results suggest DNA-PK as a novel determinant of asthma and a potential target for the treatment of the disease.

Incidence of severe combined immunodeficiency through newborn screening in a Chinese population.

BACKGROUND/PURPOSE: In order to know the true incidence of severe combined immunodeficiency (SCID) in a Chinese population, we conducted and implemented SCID newborn screening in Taiwan. METHODS: Between May 1, 2010 and December 31, 2011, the National Taiwan University Hospital Newborn Screening Center screened all newborns for T-cell lymphopenia by measuring the copy number of T-cell receptor excision circles (TRECs) and RNase P. Newborns with low TREC values were subjected to complete blood cell counts and flow cytometry. RESULTS: A total of 106,391 newborns were screened using the TREC assay over a period of 19 months. Five newborns were immediately referred for confirmatory tests, including two SCID patients and two patients with persistent T-cell lymphopenia; a third SCID patient was found 2 months after the study period. All three SCID cases received stem cell transplantation at the age of 2-5 months. We also identified five cases of 22q11.2 microdeletion syndrome. During this period, two SCID patients from among the unscreened newborns were reported, and they died at ages 3 months and 4 months, respectively. CONCLUSION: Newborn screening to measure the number of TREC copies successfully identifies newborns with T-cell lymphopenia, 22q11.2 microdeletion syndrome, and other high-risk conditions. Taken together, the incidence of T-cell lymphopenia in apparently healthy newborns is more than 1 in 11,821, and further attention to their immune functions is warranted.

Recommendations for live viral and bacterial vaccines in immunodeficient patients and their close contacts.

The present uncertainty of which live viral or bacterial vaccines can be given to immunodeficient patients and the growing neglect of societal adherence to routine immunizations has prompted the Medical Advisory Committee of the Immune Deficiency Foundation to issue recommendations based on published literature and the collective experience of the committee members. These recommendations address the concern for immunodeficient patients acquiring infections from healthy subjects who have not been immunized or who are shedding live vaccine-derived viral or bacterial organisms. Such transmission of infectious agents can occur within the hospital, clinic, or home or at any public gathering. Collectively, we define this type of transmission as close-contact spread of infectious disease that is particularly relevant in patients with impaired immunity who might have an infection when exposed to subjects carrying vaccine-preventable infectious diseases or who have recently received a live vaccine. Immunodeficient patients who have received therapeutic hematopoietic stem transplantation are also at risk during the time when immune reconstitution is incomplete or while they are receiving immunosuppressive agents to prevent or treat graft-versus-host disease. This review recommends the general education of what is known about vaccine-preventable or vaccine-derived diseases being spread to immunodeficient patients at risk for close-contact spread of infection and describes the relative risks for a child with severe immunodeficiency. The review also recommends a balance between the need to protect vulnerable subjects and their social needs to integrate into society, attend school, and benefit from peer education.

Unrelated cord blood transplantation using minimal-intensity conditioning in a 1.5-month-old infant with X-linked severe combined immunodeficiency.

BACKGROUND: Severe combined immunodeficiency (SCID) is a heterogenous disorder with profound deficiency of T/B-cell functions. The best SCID therapy requires hematopoietic stem cell transplantation (HSCT) early in life. HSCT with conditioning is necessary to achieve a long-term reconstitution of B-cell functions. However, conditioning may aggravate pre-existing infection and cause transplant-related toxicity, especially in very young infants. Hence, the intensity of conditioning should be reduced to allow the reconstitution of immunity including B cells to the extent that prevents transplant-related toxicity and delayed complications. METHODS: An infant with a family history of X-linked SCID (X-SCID) was diagnosed with X-SCID disorder soon after birth. The infant exhibited cytomegalovirus (CMV) infection despite being strictly isolated. At 1.5 months of age, we performed an unrelated cord blood transplantation (CBT) with a less intensity conditioning regimen: fludarabine (125 mg/m2) + melphalan (80 mg/m2). We evaluated the efficacy of reconstitution by assessing B-cell function and growth and psychomotor development at 5 years and 7 months after CBT. RESULTS: The clinical course after CBT was uneventful after CBT. The CMV infection was fully controlled by ganciclovir or foscavir therapy, which was discontinued at day 55 after CBT. Furthermore, immunoglobulin (Ig) replacement therapy was also discontinued at 6 months after CBT. A sufficient proportion of CD27+ memory B cells was developed, which was essential for an effective vaccination and prevention of infections. While the B-cell chimerism became recipient-dominant, the Ig replacement therapy was substituted by very successful post-vaccine immunity acquisition after CBT. The analysis of the general developmental parameters showed that chemotherapy did not cause any delay in growth and psychomotor development. CONCLUSIONS: The CBT therapy with this conditioning regimen was well tolerated and induced an effective reconstitution of B-cell functions in an X-SCID infant under the 3 months of age.

Haploidentical Transplant in Radiosensitive Severe Combined Immunodeficiency Disease.

Severe combined immunodeficiency (SCID) is an inborn error of immunity invariably resulting in mortality in infancy until managed by hematopoietic stem cell transplant (HSCT). We present an unusual case of SCID with a rare mutation involving the non-homologous end-joining 1 (NHEJ1) gene, where a haploidentical HSCT was carried out with modified conditioning and graft versus host prophylaxis regimen using proteasome inhibitor bortezomib with a successful outcome.

First Occurrence of Plasmablastic Lymphoma in Adenosine Deaminase-Deficient Severe Combined Immunodeficiency Disease Patient and Review of the Literature.

Adenosine deaminase-deficient severe combined immunodeficiency disease (ADA-SCID) is a primary immune deficiency characterized by mutations in the ADA gene resulting in accumulation of toxic compounds affecting multiple districts. Hematopoietic stem cell transplantation (HSCT) from a matched donor and hematopoietic stem cell gene therapy are the preferred options for definitive treatment. Enzyme replacement therapy (ERT) is used to manage the disease in the short term, while a decreased efficacy is reported in the medium-long term. To date, eight cases of lymphomas have been described in ADA-SCID patients. Here we report the first case of plasmablastic lymphoma occurring in a young adult with ADA-SCID on long-term ERT, which turned out to be Epstein-Barr virus associated. The patient previously received infusions of genetically modified T cells. A cumulative analysis of the eight published cases of lymphoma from 1992 to date, and the case here described, reveals a high mortality (89%). The most common form is diffuse large B-cell lymphoma, which predominantly occurs in extra nodal sites. Seven cases occurred in patients on ERT and two after haploidentical HSCT. The significant incidence of immunodeficiency-associated lymphoproliferative disorders and poor survival of patients developing this complication highlight the priority in finding a prompt curative treatment for ADA-SCID.

Analysis of Hepatitis C Virus Particle Heterogeneity in Immunodeficient Human Liver Chimeric fah-/- Mice.

BACKGROUND & AIMS: Hepatitis C virus (HCV) is a leading cause of chronic liver diseases and the most common indication for liver transplantation in the United States. HCV particles in the blood of infected patients are characterized by heterogeneous buoyant densities, likely owing to HCV association with lipoproteins. However, clinical isolates are not infectious in vitro and the relative infectivity of the particles with respect to their buoyant density therefore cannot be determined, pointing to the need for better in vivo model systems. METHODS: To analyze the evolution of the buoyant density of in vivo-derived infectious HCV particles over time, we infected immunodeficient human liver chimeric fumaryl acetoacetate hydrolase-/- mice with J6/JFH1 and performed ultracentrifugation of infectious mouse sera on isopicnic iodixanol gradients. We also evaluated the impact of a high sucrose diet, which has been shown to increase very-low-density lipoprotein secretion by the liver in rodents, on lipoprotein and HCV particle characteristics. RESULTS: Similar to the severe combined immunodeficiency disease/Albumin-urokinase plasminogen activator human liver chimeric mouse model, density fractionation of infectious mouse serum showed higher infectivity in the low-density fractions early after infection. However, over the course of the infection, viral particle heterogeneity increased and the overall in vitro infectivity diminished without loss of the human liver graft over time. In mice provided with a sucrose-rich diet we observed a minor shift in HCV infectivity toward lower density that correlated with a redistribution of triglycerides and cholesterol among lipoproteins. CONCLUSIONS: Our work indicates that the heterogeneity in buoyant density of infectious HCV particles evolves over the course of infection and can be influenced by diet.

Severe Combined Immunodeficiency Disorders.

Severe combined immunodeficiency disorders represent pediatric emergencies due to absence of adaptive immune responses to infections. The conditions result from either intrinsic defects in T-cell development (ie, severe combined immunodeficiency disease [SCID]) or congenital athymia (eg, complete DiGeorge anomaly). Hematopoietic stem cell transplant provides the only clinically approved cure for SCID, although gene therapy research trials are showing significant promise. For greatest survival, patients should undergo transplant before 3.5 months of age and before the onset of infections. Newborn screening programs have yielded successful early identification and treatment of infants with SCID and congenital athymia in the United States.

Diagnosing primary immunodeficiency: a practical approach for the non-immunologist.

OBJECTIVE: This review will provide an overview of the most common clinical presentations of primary immunodeficiency (PI), navigating through various affected organ systems. The goal is to accurately portray the high variability of this disease and provide a resource that helps to raise the index of suspicion of PI among physicians, aid in recognition of various PI disorders, and trigger more frequent screenings with appropriate referrals to immunologists for further evaluation and treatment. SUMMARY: Patients with PI comprise more than 200 defined genetic abnormalities. Patients have an array of clinical manifestations, ranging from the most widely associated recurrent and chronic bacterial infections to other associated comorbid conditions involving many organ systems. There is still considerable delay between the onset of symptoms and the time of diagnosis of PI. This review will present an overview of the clinical manifestations that will enhance a physician's recognition of a possible PI. Particular emphasis is placed on the pathogens associated with the specific arm of the immune system that is related to each particular type of PI. The initial immune evaluation is described, which together with the history and physical exam can help focus the physician on the immune compartment most likely associated with a PI. CONCLUSIONS: Understanding the types of PI and the related clinical manifestations can help physicians see beyond the presenting symptoms and lead to improved recognition and diagnosis of PI. Timely diagnosis is of utmost importance in PI, as recent advances in bone transplantation and immunoglobulin replacement therapy, as well as future gene therapies, provide effective ways to prevent significant mortality and morbidity.