Phenotypic and Immunological Characterization of Patients with Activated PI3Kδ Syndrome 1 Presenting with Autoimmunity.

PURPOSE: Autoimmunity is a significant feature of APDS1 patients. We aimed to explore the pathogenic immune phenotype and possible mechanisms of autoimmunity in APDS1 patients. METHODS: The clinical records and laboratory data of 42 APDS1 patients were reviewed. Immunophenotypes were evaluated by multiparametric flow cytometry. Autoantibodies were detected via antigen microarray analysis. RESULTS: A total of 42 children with PIK3CD gene mutations were enrolled. Immunological tests revealed increased proportions of effector memory cells (86%) and central memory cells (59%) among CD4+ T cells; increased proportions of effector memory cells (83%) and terminally differentiated effector memory T cells (38%) among CD8+ T cells. Fewer CD3+ T cells and B cells and higher IgG levels were reported in patients with autoimmunity. The proportion of Tregs was decreased, and the proportions of Th9, Tfh, and Tfr cells were increased in APDS1 patients. Among APDS1 patients, higher proportion of Th2 and Tfr cells were found in those with autoimmunity. The proportions of CD11c+ B and CD21lo B cells in patients with autoimmunity were significantly increased. Antigen microarray analysis revealed a wide range of IgG/IgM autoantibodies in patients with APDS1. In patients with autoimmunity, the proportion of Tfr might be positively correlated with autoantibodies. CONCLUSIONS: The pathogenic immune phenotype of APDS1 patients included (1) deceased CD3+ T-cell and B-cell counts and increased IgG levels in patients with autoimmunity, (2) an imbalanced T helper cell subset, (3) increased proportions of autoreactive B cells, and (4) distinct autoantibody reactivities in patients with autoimmunity.

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.

Severe G6PD deficiency leads to recurrent infections and defects in ROS production: Case report and literature review.

Purpose: Severe glucose-6-phosphate dehydrogenase (G6PD) deficiency can lead to reduced nicotinamide adenine dinucleotide phosphate oxidase activity in phagocytes, resulting in immunodeficiency, with a limited number of reported cases. Here, we aimed to report a child with severe G6PD deficiency in China and investigate the mechanism of his recurrent infections. Methods: The clinical manifestations and immunological phenotypes of this patient were retrospectively collected. Gene mutation was detected by whole-exome sequencing and confirmed by Sanger sequencing. Dihydrorhodamine (DHR) analysis was performed to measure the respiratory burst of neutrophils. Messenger ribonucleic acid and protein levels were detected in the patient under lipopolysaccharide stimulation by real-time quantitative reverse transcription polymerase chain reaction and Western blot. A review of the literature was performed. Results: A male child with G6PD deficiency presented with recurrent respiratory infections, Epstein‒Barr virus infection and tonsillitis from 8 months of age. Gene testing revealed that the proband had one hemizygous mutation in the G6PD gene (c.496 C>T, p. R166C), inherited from his mother. This mutation might affect hydrophobic binding, and the G6PD enzyme activity of the patient was 0. The stimulation indexes of the neutrophils in the patient and mother were 22 and 37, respectively. Compared with healthy controls, decreased reactive oxygen species (ROS) production was observed in the patient. Activation of nuclear factor kappa-B (NF-κB) signaling was found to be influenced, and the synthesis of tumor necrosis factor alpha (TNF-α) was downregulated in the patient-derived cells. In neutrophils of his mother, 74.71% of the X chromosome carrying the mutated gene was inactivated. By performing a systematic literature review, an additional 15 patients with severe G6PD deficiency and recurrent infections were identified. Four other G6PD gene mutations have been reported, including c.1157T>A, c.180_182del, c.514C>T, and c.953_976del. Conclusion: Severe G6PD deficiency, not only class I but also class II, can contribute to a chronic granulomatous disease-like phenotype. Decreased reactive oxygen species synthesis led to decreased activation of the NF-κB pathway in G6PD-deficient patients. Children with severe G6PD deficiency should be aware of immunodeficiency disease, and the DHR assay is recommended to evaluate neutrophil function for early identification.

Rapid diagnosis of Talaromyces marneffei infection by metagenomic next-generation sequencing technology in a Chinese cohort of inborn errors of immunity.

Talaromyces marneffei (T. marneffei) is an opportunistic pathogen. Patients with inborn errors of immunity (IEI) have been increasingly diagnosed with T. marneffei in recent years. The disseminated infection of T. marneffei can be life-threatening without timely and effective antifungal therapy. Rapid and accurate pathogenic microbiological diagnosis is particularly critical for these patients. A total of 505 patients with IEI were admitted to our hospital between January 2019 and June 2022, among whom T. marneffei was detected in 6 patients by metagenomic next-generation sequencing (mNGS), and their clinical and immunological characteristics were summarized. We performed a systematic literature review on T. marneffei infections with published immunodeficiency-related gene mutations. All patients in our cohort were confirmed to have genetic mutations in IL12RB1, IFNGR1, STAT1, STAT3, and CD40LG. T. marneffei was detected in both the blood and lymph nodes of P1 with IL12RB1 mutations, and the clinical manifestations were serious and included recurrent fever, weight loss, severe anemia, splenomegaly and lymphadenopathy, all requiring long-term antifungal therapy. These six patients received antifungal treatment, which relieved symptoms and improved imaging findings. Five patients survived, while one patient died of sepsis after hematopoietic stem cell transplantation. The application of mNGS methods for pathogen detection in IEI patients and comparison with traditional diagnosis methods were investigated. Traditional diagnostic methods and mNGS tests were performed simultaneously in 232 patients with IEI. Compared to the traditional methods, the sensitivity and specificity of mNGS in diagnosing T. marneffei infection were 100% and 98.7%, respectively. The reporting time for T. marneffei detection was approximately 26 hours by mNGS, 3-14 days by culture, and 6-11 days by histopathology. T. marneffei infection was first reported in IEI patients with IL12RB1 gene mutation, which expanded the IEI lineage susceptible to T. marneffei. For IEI patients with T. marneffei infection, we highlight the application of mNGS in pathogenic detection. mNGS is recommended as a front-line diagnostic test for rapidly identifying pathogens in complex and severe infections.

Cellular Mechanisms Underlying B Cell Abnormalities in Patients With Gain-of-Function Mutations in the PIK3CD Gene.

Background: Activated phosphoinositide 3 kinase (PI3K) -delta syndrome (APDS) is an inborn error of immunity with variable clinical phenotype of immunodeficiency and immune dysregulation and caused by gain-of-function mutations in PIK3CD. The hallmark of immune phenotype is increased proportions of transitional B cells and plasmablasts (PB), progressive B cell loss, and elevated levels of serum IgM. Objective: To explore unique B cell subsets and the pathomechanisms driving B cell dysregulation beyond the transitional B cell stage in APDS. Methods: Clinical and immunological data was collected from 24 patients with APDS. In five cases, we performed an in-depth analysis of B cell phenotypes and cultured purified naïve B cells to evaluate their survival, activation, Ig gene class switch recombination (CSR), PB differentiation and antibody secretion. We also analyzed PB differentiation capacity of sorted CD27-IgD- double-negative B (DNB) cells. Results: The patients had increased B cell sizes and higher proportions of IgM+ DNB cells than healthy controls (HC). Their naïve B cells exhibited increased death, impaired CSR but relatively normal PB differentiation. Upon stimulation, patient's DNB cells secreted a similar level of IgG but a higher level of IgM than DNB cells from HC. Targeted therapy of PI3K inhibition partially restored B cell phenotypes. Conclusions: The present study suggests additional mechanistic insight into B cell pathology of APDS: (1) decreased peripheral B cell numbers may be due to the increased death of naïve B cells; (2) larger B cell sizes and expanded DNB population suggest enhanced activation and differentiation of naïve B cells into DNB cells; (3) the impaired CSR yet normal PB differentiation can predominantly generate IgM-secreting cells, resulting in elevated IgM levels.

Variant Type X91+ Chronic Granulomatous Disease: Clinical and Molecular Characterization in a Chinese Cohort.

PURPOSE: We aimed to report the clinical and immunological characteristics of variant type X91+ chronic granulomatous disease (CGD) in a Chinese cohort. METHODS: The clinical manifestations and immunological phenotypes of patients with X91+ CGD were collected. A dihydrorhodamine (DHR) analysis was performed to evaluate neutrophil function. Gp91phox protein expression was determined using extracellular staining with the monoclonal antibody (mAb) 7D5 and flow cytometry. RESULTS: Patients with X91+ CGD accounted for 8% (7/85) of all patients with CGD. The median age of onset in the seven patients with X91+ CGD was 4 months. Six patients received the BCG vaccine, and 50% (3/6) had probable BCG infections. Mycobacterium tuberculosis infection was prominent. The most common sites of infection were the lung (6/7), lymph nodes (5/7), and soft tissue (3/7). Two patients experienced recurrent oral ulcers. The stimulation index (SI) of the patients with X91+ CGD ranged widely from 1.9 to 67.3. The difference in the SI among the three groups of patients (X91+ CGD, X91- CGD, and X910 CGD) was statistically significant (P = 0.0071). The three groups showed no significant differences in onset age, diagnosis age, or severe infection frequency. CYBB mutations associated with X91+ CGD were commonly located in the second transmembrane or intracellular regions. Three novel X91+ CGD-related mutations (c.1462-2 A > T, c.1243C > T, and c.925G > A) were identified. CONCLUSIONS: Variant type X91+ CGD may result in varied clinical manifestations. Moreover, the laboratory findings might indicate a moderate neutrophil SI. We should deepen our understanding of variant X91+ CGD to prevent missed diagnoses.

Chromosomal abnormalities related to fever of unknown origin in a Chinese pediatric cohort and literature review.

BACKGROUND: Fever of unknown origin (FUO) has been difficult to diagnose in pediatric clinical practice. With the gradual change in the disease spectrum, genetic factors have received increasing attention. Limited studies have shown an association between FUO and chromosomal abnormalities. In this study, we investigated the clinical and genetic characteristics of patients with FUO presenting with chromosomal abnormalities in a Chinese pediatric cohort. RESULTS: Chromosomal abnormalities were detected in 5.5% (8/145) of the patients with FUO. Six patients with inflammatory fever presented with pharyngitis/amygdalitis (4/6), oral aphthous ulcer (2/6), digestive symptoms (3/6), developmental delay (4/6) and elevated C-reactive protein levels (6/6) during fever. These patients were often considered to have systemic inflammatory diseases, such as Behcet's disease or systemic juvenile idiopathic arthritis. Trisomy 8, 7q11.23 dup, 3p26.3-p26.1 del/17q12 dup, 22q11.21 del, and 6q23.3-q24.1 del were identified in patients with inflammatory fever. The TNFAIP3 gene was included in the 6q23.3-q24.1 deletion fragment. Two patients with central fever were characterized by facial anomalies, developmental delay, seizures and no response to antipyretic drugs and were identified as carrying the de novo 18q22.3-q23 del. By performing a literature review, an additional 19 patients who had FUO and chromosomal abnormalities were identified. Trisomy 8, 6q23.2-q24.3 del and 18q22.3-q23 del were reported to present as fever, similar to the findings of our study. CONCLUSIONS: We emphasized the important role of detecting chromosomal abnormalities in patients with FUO, especially in patients with systemic inflammatory manifestations or developmental delay. Identifying chromosomal abnormalities may change the diagnosis and management of patients with FUO.

In vitro human skin percutaneous penetration: does a second topical application effect flux of first application?

INTRODUCTION: Skin care products are often utilized in conjunction with topical treatment for skin disease. However, these appears insufficient body of experimental data to advise the health care worker or patient. Examine penetration effect (hence potential for altering efficacy and toxicity) - dosing with one topical after another and how quickly such a potential phenomenon might occur. METHODS: A marketed moisturizer applied on human skin with an in vitro diffusion system. At 1, 15, and 30 min post application, [14C]-benzoic acid dosed the same skin site for 24 h. Amounts of chemical retained in skin and permeation flux rats were measured to determine penetration effect of the prior moisturizer application. RESULTS: Exposure of a water-enriched moisturizer before a hydrophilic chemical immediate application favors the chemical penetration, especial in 1 and 15 min moisturizer exposure groups. The enhancement effect was expressed as an earlier lag time and a rapid absorption peak when compared to related non-moisturizer control. CONCLUSION: This experiment opens up a large door: what would be the result with many complex topical products and different tracers was used here, of varying hydrophilicity and lipophilicity. We do not wish to overgeneralize until such studies are confirmed in vivo.

Effect of soak and smear on [14C]-hydrocortisone in vitro human skin percutaneous penetration.

INTRODUCTION: 'Soak and smear' method, water soaking to induce skin hydration followed by topical corticoids application suggests effectiveness in clinical dermatological practice. We investigate one possible mechanism of soaking times effect on drug partitioning and diffusion rates in skin and its proposed efficacy. METHODS: Utilizing an in vitro flow-through diffusion system to evaluate efficacy of the 'soak and smear' method following 0.5, 8, and 20 min water soaking and [14C]-hydrocortisone topical application on human skin to probe the possibility of percutaneous penetration enhancement. RESULTS: In water-soak groups, more [14C]-hydrocortisone was absorbed and retained in stratum corneum and epidermis, whereas, in the control (no soak) more was in the deep skin-dermis and receptor fluid. These differences between water-soak groups and the control are statistically significant (p < .05). CONCLUSION: Effect of 'soak and smear' on skin absorption and penetration depends on interaction of individual drug's physicochemical property, stratum corneum hydration, and stratum corneum-epidermoid barrier status. Water soaking (≤ 20 min) induced skin hydration increases [14C]-hydrocortisone absorption and retention into the upper skin layer but not deep layers. This could support the proposed hypothesis of clinical dermatological treatment of hydrocortisone to local skin inflammations should the epidermis be found to be a key target for atopic dermatitis therapy.

Efficacy of tocilizumab therapy in a patient with severe pancytopenia associated with a STAT3 gain-of-function mutation.

BACKGROUND: We aimed to report the clinical characteristics, immunological features, and treatment of one patient with a de novo STAT3 gain-of-function mutation identified by next generation sequencing. We investigated the efficacy of tocilizumab therapy in immune dysregulation diseases caused by STAT3 mutation. RESULTS: The patient was a 16-year-old girl. She presented with recurrent respiratory infections and chronic diarrhea after birth. She had life-threatening autoimmune pancytopenia at 14 years old. After receiving glucocorticoid therapy, she developed diabetes. However, her pancytopenia relapsed when the glucocorticoid was tapered. Next-generation sequencing showed a de novo heterozygous mutation in the STAT3 gene, c.1261G > A (p. G421R), which was previously described as a gain-of-function mutation. After tocilizumab therapy, her pancytopenia fully resolved, and insulin and glucocorticoid therapies were gradually discontinued within 12 months. She had lymphopenia and an inverted CD4/CD8 ratio before therapy. Lymphocyte subpopulation analysis indicated an expansion of effector memory CD4+, effector memory CD8+ and central memory CD4+ T cells. The proportions of memory B cells and naive CD4+ T cells were decreased, and the proportion of naïve B cells was increased. None of the abnormal lymphocytic changes improved significantly. STAT3 GOF mutations were identified by next gene sequencing in those with early-onset multi-organ autoimmunity. Including our patient, 13 patients with STAT3 GOF mutations received targeted treatment. Twelve of them were treated with tocilizumab alone or combination tocilizumab with JAK inhibitor, and ten patients improved. CONCLUSIONS: Gene sequencing should be performed for patients with early-onset refractory or multiorgan immune dysregulation diseases. Targeted drugs can effectively improve the clinical problems associated with STAT3 gain-of-function mutations, while nontargeted immunosuppressive therapy is usually insufficient.

Follicular pathway role in chemical warfare simulants percutaneous penetration.

Chemical warfare (CW) exposure could be fatal to military and civilians through skin contamination. Our work and others focus on investigating stratum corneum reservoir with less regards to skin appendageal routes including hair follicles. Here, C-14 CW simulants (CWS) with specific activity of 0.1 mCi/ml were tested on abdominal and scalp human cadaver skin using flow-through diffusion system. Quantitative analysis of simulants in skin compartments were performed using scintillation counter. Scalp permeation of dipropylene glycol monomethyl ether (DPGME), diisopropyl methylphosphonate (DIMP) and methyl salicylate (MeS) exceed abdominal skin by 8%, 15%, and 6% (p value < 0.05) of applied dose, respectively. DPGME and DIMP (most hydrophilic) showed earlier permeation peak time (Tmax) through scalp skin at 2 and 4 h, respectively, comparing with 6 h with abdominal skin. The percentage of applied dose of DPGME and DIMP retained in human skin membrane (SC, epidermis, and viable dermis) showed no statistically significant difference between tested abdominal and scalp skin samples (p value >0.05). The percentage of applied dose of MeS in scalp showed higher partitioning in stratum corneum and viable epidermis than abdominal skin (p value <0.05). In conclusion, human scalp showed greater total skin absorption than abdominal skin. This work points to a qualitative importance of high follicular density body regions in percutaneous penetration and suggests that transfollicular pathway might have a significant role in early stage permeation of chemical warfare simulants. However, the difference noticed here between scalp and abdominal skin could be attributed to regional variability in anatomy, physiology, and barrier characteristics.

Effect of superabsorbent polymers (SAP) and metal organic frameworks (MOF) wiping sandwich patch on human skin decontamination and detoxification in vitro.

Most chemical warfare agents partition rapidly into stratum corneum (SC) and subsequently slowly diffuse through - or are retained in the membrane. Since chemicals can interact with SC components during the process, skin decontamination poses a challenging yet important problem. To address these issues, we have developed a new method in combination with wet and dry decon technologies with new materials for emergency or delayed contamination scenarios. An in vitro human skin diffusion system was employed to model various dermal exposures of radiolabeled chemical warfare simulants, followed by surface decontamination with metal organic frameworks (MOFs), super-absorbent polymers (SAP), and/or dermal decontamination gel (DDGel). All samples measured for radioactive recovery and acetylcholinesterase activity to ascertain relative decon efficacy. Results demonstrated powerful water absorption of SAP, strong catalysis of UiO-66 MOF, and decon enhancement of pre-wetting surface contaminants. SAP had no interfering interactions with MOF yet provided additional benefits as porosity and reactivity that allowed for fast liquidized chemical transportation, absorption, and degeneration. We then designed a cotton-based SAP/MOF patch that worked cooperatively in decontamination and detoxification. Together with pre-wet, SAP/MOF wipe, and DDGel applications, maximum effect was observed in early and/or extended dermal exposure, and no "wash-in" effect occurred.

LIG4 syndrome: clinical and molecular characterization in a Chinese cohort.

BACKGROUND: DNA Ligase IV (LIG4) syndrome is a rare disease with few reports to date. Patients suffer from a broad spectrum of clinical features, including microcephaly, growth retardation, developmental delay, dysmorphic facial features, combined immunodeficiency, and malignancy predisposition. There may be a potential association between genotypes and phenotypes. We investigated the characteristics of LIG4 syndrome in a Chinese cohort. RESULTS: All seven patients had growth restriction. Most patients (6/7) had significant microcephaly (< - 3 SD). Recurrent bacterial infections of the lungs and intestines were the most common symptoms. One patient had myelodysplastic syndromes. One patient presented with an inflammatory bowel disease (IBD)-like phenotype. Patients presented with combined immunodeficiency. The proportions of naïve CD4+ and naïve CD8+ T cells decreased notably in five patients. All patients harbored compound heterozygous mutations in the LIG4 gene, which consisted of a missense mutation (c.833G > T, p.R278L) and a deletion shift mutation, primarily c.1271_1275delAAAGA (p.K424Rfs*20). Two other deletion mutations, c.1144_1145delCT and c.1277_1278delAA, were novel. Patients with p.K424Rfs*20/p.R278 may have milder dysmorphism but more significant IgA/IgM deficiency compared to the frequently reported genotype p.R814X/p.K424Rfs*20. One patient underwent umbilical cord blood stem cell transplantation (UCBSCT) but died. CONCLUSIONS: The present study reported the clinical and molecular characteristics of a Chinese cohort with LIG4 syndrome, and the results further expand the phenotypic and genotypic spectrum and our understanding of genotype-to-phenotype correlations in LIG4 syndrome.

Low-Dose Pioglitazone does not Increase ROS Production in Chronic Granulomatous Disease Patients with Severe Infection.

PURPOSE: We sought to further investigate the efficacy and safety of pioglitazone for chronic granulomatous disease (CGD) patients with severe infection. METHODS: CGD patients with severe infection were enrolled and treated with pioglitazone for 90 days. The degree of improvement in infection and the changes of dihydrorhodamine-123 (DHR) were used to evaluate the efficacy of pioglitazone. The adverse reaction of pioglitazone was also investigated. RESULTS: We planned to enroll 30 patients at first in the study. However, the study was terminated due to negative results from all 3 enrolled patients. The 3 patients were diagnosed with CGD by clinical characteristics, DHR analysis, and genetics analysis. Mutations were CYBB (c.177C>A; p.C59X) in P1, CYBB (c.1498G>T; p.D500Y) in P2, and NCF2 (c.137T>G; p.M46R) in P3, respectively. The age of onset of the 3 patients was within 2 years after birth. The most common sites of infection were lung, lymph node, skin, and soft tissue, which were experienced in all 3 patients. The age of administration with pioglitazone was 5.2 years, 16 years and 11.1 years, respectively. The 3 patients experienced no improvement in severity of infection and stimulation index of the DHR did not also improve after receiving pioglitazone 10, 45 and 90 days, respectively. No drug-related adverse reaction was found during the period of pioglitazone. CONCLUSIONS: Low dose of pioglitazone did not improve the severity of infection and production of ROS in CGD patients with severe infection.

Current Status of the Management of Mendelian Susceptibility to Mycobacterial Disease in Mainland China.

PURPOSE: Although many studies have investigated Mendelian susceptibility to mycobacterial disease (MSMD) worldwide, there is no report of the long-term clinical management and prognosis for MSMD in China. METHODS: This is a cohort study from January 2000 to June 2018. Three hundred and twenty-four patients with bacillus Calmette-Guérin (BCG) infection were diagnosed during this period, and those with MSMD diagnosed by genetic and functional experiments were enrolled in the study. The clinical and genetic characteristics and management of these MSMD patients were summarized. RESULTS: Thirty patients diagnosed with MSMD were followed up. The age at the follow-up end point ranged from 5 to 173 months. Among the patients, IL12RB1 mutations were identified in 22, IFNGR1 mutations in 5, STAT1 mutations in 2, and IFNGR2 mutation in 1. The medium age at onset was 3 months. BCG infection involved multiple organs, including regional infection (8/30; 26.7%) or distant or disseminated infection (22/30; 73.3%). Ten percent (30/324) of patients with BCG infection had a confirmed MSMD diagnosis. Protein expression of IL12RB1 or IFNGR1 was decreased in all patients with IL12RB1 or IFNGR1 mutation, respectively, as indicated by flow cytometry. In addition, 77.8% of patients received rhIFN-γ treatment, which can improve the prognosis of patients with IL12RB1 deficiency. Two patients received stem cell transplantation. Twenty-five patients remained alive at the time of publication. CONCLUSION: MSMD is an important cause of BCG infection. Flow cytometric detection of IL12RB1 and IFNGR1 expression is very useful for rapid MSMD diagnosis. rhIFN-γ therapy is effective in patients with MSMD, particularly improving prognosis in those with IL12RB1 deficiency.

Report of a Chinese Cohort with Leukocyte Adhesion Deficiency-I and Four Novel Mutations.

PURPOSE: We aimed to report the characteristics of leukocyte adhesion deficiency-I (LAD-I) and four novel mutations in the ITGB2 gene in a Chinese cohort. METHODS: Seven patients with LAD-I were reported in our study. Clinical manifestations and immunological phenotypes were reviewed. The expression of CD18 was detected by flow cytometry. Next-generation sequencing (NGS) and Sanger sequencing were performed to identify gene mutations. RESULTS: The mean onset age of all the patients was 1.3 months. Recurrent bacterial infections of the skin and lungs were the most common symptoms. Most patients (6/7) had delayed cord separation. The number of white blood cells (WBC) was increased significantly, except that two patients had a mild increase in the number of WBC during infection-free periods. The expression of CD18 was very low in all patients. Homozygous or compound heterozygous mutations in the ITGB2 gene were identified in each patient. Four mutations were novel, including c.1794dupC (p.N599Qfs*93), c.1788C>A (p.C596X), c.841-849del9, and c.741+1delG. Two patients had large deletions of the ITGB2 gene. Five patients were cured by hematopoietic stem cell transplantation (HSCT). CONCLUSIONS: This study reported the clinical and molecular characteristics of a Chinese patient cohort. It is helpful in understanding the current status of the disease in China.

Novel Heterogeneous Mutation of TNFAIP3 in a Chinese Patient with Behçet-Like Phenotype and Persistent EBV Viremia.

PURPOSE: Tumor necrosis factor alpha-induced protein 3 (TNFAIP3, A20) is a negative regulator of the nuclear factor-κB (NF-κB) pathway. It has recently been recognized that TNFAIP3 deficiency leads to early onset of autoinflammatory and autoimmune syndrome resembling Behçet's disease. Here, we report a novel mutation in TNFAIP3 in a Chinese patient, who had Behçet-like phenotype and persistent Epstein-Barr virus (EBV) viremia. METHODS: The clinical data were collected. Immunological function was detected. Gene mutation was detected by whole-exome sequencing (WES) and confirmed by Sanger sequencing. mRNA and protein levels were detected in the patient under lipopolysaccharide (LPS) stimulation by real-time PCR and Western blot. RESULTS: The patient is a 13-year-old boy, presenting with intermittent fever for 5 months, who also experienced diffuse lymphadenopathy, arthritis, and recurrent multiple gastrointestinal ulcers. EBV DNA was detected in the serum and peripheral blood mononuclear cells of the patient. The immunological phenotype showed increased proportion of double-negative T cells (CD3+CD4-CD8-). A novel missense mutation (c.1428G > A) locating at the zinc fingers 2 (ZF2) domain of TNFAIP3 inherited from his mother was confirmed. Compared with age-matched healthy controls, decrease expression of A20 was observed in the patient. The NF-κB pathway was found to be overactivated, and the synthesis of TNF-α was upregulated in the patient-derived cells. However, cells from the mother showed a milder response to LPS than cells from the patient. CONCLUSIONS: The present research indicated that the TNFAIP3 mutation of c.1428G > A (p.M476I) leads to the reduced suppression of NF-κB activation and accounted for the autoinflammatory phenotype and persistent EBV viremia in the patient.

A Chinese DADA2 patient: report of two novel mutations and successful HSCT.

Deficiency of adenosine deaminase 2 (DADA2) is an autoinflammatory disease caused by autosomal recessive mutations in Cat Eye Syndrome Chromosome Region 1 (CECR1) gene. In this report, we aimed to describe the clinical manifestations, immunological features, genotype, and treatments of one Chinese patient with novel CECR1 gene mutations. This patient initially presented with recurrent fever and rashes from the age of 3 months, but no pathogen was found. She then developed dry gangrene of the fingers at 5 months of age. Laboratory examinations revealed elevated levels of C-reactive protein and thrombocytes. The expression of interleukin-6 (IL-6) and IL-8 were both elevated. Sequencing results revealed that she had compound heterozygous mutations in CECR1 gene (c.1211T>C, p.Phe404Ser and c.1114 G>A, p.Val372Met). Subsequently, treatment with anti-IL-6 (tocilizumab) was started. However, she developed blurred vision in the right eye with occlusion of the central retinal artery, accompanied by unsteady gait. Magnetic resonance imaging (MRI) showed infarction of the right thalamus. Finally, she underwent hematopoietic stem cell transplantation (HSCT) and is currently in remission. Our findings suggest that HSCT could cure this disease.

Report of a Chinese Cohort with Activated Phosphoinositide 3-Kinase δ Syndrome.

PURPOSE: We aimed to report the clinical manifestations and immunological features of activated phosphatidylinositol 3-kinase δ syndrome 1 (APDS1) in a Chinese cohort. Moreover, we investigated the efficacy and safety of rapamycin therapy for Chinese patients with APDS1. METHODS: Fifteen Chinese patients with APDS1 from 14 unrelated families were enrolled in this study. These patients were diagnosed based on clinical features, immunological phenotype, and whole-exome sequencing. Four patients were treated with rapamycin, and the clinical efficacy and safety of rapamycin were observed. The changes of phosphorylation of Akt and mammalian target of rapamycin (mTOR) signaling pathway after rapamycin treatment were detected by flow cytometry and real-time PCR. RESULTS: The common clinical manifestations of the patients included lymphadenopathy (93%), recurrent sinopulmonary infections (93%), hepatosplenomegaly (93%), and diarrhea (78%). Epstein-Barr virus (EBV) (80%) and fungus (Aspergillus) (47%) were the most common pathogens. Immunological phenotype included elevated Immunoglobulin (Ig) M levels (100%), decreased naive T cells, increased senescent T cells, and expanded transitional B cells. Whole-exome sequencing indicated that 13 patients had heterogeneous PIK3CD E1021K mutations, 1 patient had heterogeneous E1025G mutation and 1 patient had heterogeneous Y524N mutation. Gain-of-function (GOF) PIK3CD mutations increased the phosphorylation of the Akt-mTOR signaling pathway. Four patients underwent rapamycin therapy, experiencing substantial improvement in clinical symptoms and immunological phenotype. Rapamycin inhibited the activated Akt-mTOR signaling pathway. CONCLUSIONS: We described 15 Chinese patients with APDS1. Treatment with the mTOR inhibitor rapamycin improved patient outcomes.