Multiple Immune Defects in Two Patients with Novel DOCK2 Mutations Result in Recurrent Multiple Infection Including Live Attenuated Virus Vaccine.

The dedicator of cytokinesis 2(DOCK2) protein, an atypical guanine nucleotide exchange factor (GEFs), is a member of the DOCKA protein subfamily. DOCK2 protein deficiency is characterized by early-onset lymphopenia, recurrent infections, and lymphocyte dysfunction, which was classified as combined immune deficiency with neutrophil abnormalities as well. The only cure is hematopoietic stem cell transplantation. Here, we report two patients harboring four novel DOCK2 mutations associated with recurrent infections including live attenuated vaccine-related infections. The patient's condition was partially alleviated by symptomatic treatment or intravenous immunoglobulin. We also confirmed defects in thymic T cell output and T cell proliferation, as well as aberrant skewing of T/B cell subset TCR-Vß repertoires. In addition, we noted neutrophil defects, the weakening of actin polymerization, and BCR internalization under TCR/BCR activation. Finally, we found that the DOCK2 protein affected antibody affinity although with normal total serum immunoglobulin. The results reported herein expand the clinical phenotype, the pathogenic DOCK2 mutation database, and the immune characteristics of DOCK2-deficient patients.

Loss of Function Mutation in ELF4 Causes Autoinflammatory and Immunodeficiency Disease in Human.

Monogenic autoinflammatory diseases (mAIDs) are a heterogeneous group of diseases affecting primarily innate immunity, with various genetic causes. Genetic diagnosis of mAIDs can assist in the patient's management and therapy. However, a large number of sporadic and familial cases remain genetically uncharacterized. Deficiency in ELF4, X-linked (DEX) is recently identified as a novel mAID. Here, we described a pediatric patient suffering from recurrent viral and bacterial respiratory infection, refractory oral ulcer, constipation, and arthritis. Whole-exome sequencing found a hemizygous variant in ELF4 (chrX:129205133 A > G, c.691 T > C, p.W231R). Using cells from patient and point mutation mice, we showed mutant cells failed to restrict viral replication effectively and produced more pro-inflammatory cytokines. RNA-seq identified several potential critical antiviral and anti-inflammation genes with decreased expression, and ChIP-qPCR assay suggested mutant ELF4 failed to bind to the promoters of these genes. Thus, we presented the second report of DEX.

Activated Phosphoinositide 3-Kinase δ Syndrome: a Large Pediatric Cohort from a Single Center in China.

PURPOSE: Activated phosphoinositide 3-kinase δ syndrome (APDS) is a primary immunodeficiency first described in 2013, which is caused by gain-of-function mutations in PIK3CD or PIK3R1, and characterized by recurrent respiratory tract infections, lymphoproliferation, herpesvirus infection, autoimmunity, and enteropathy. We sought to review the clinical phenotypes, immunological characteristics, treatment, and prognosis of APDS in a large genetically defined Chinese pediatric cohort. METHODS: Clinical records, radiology examinations, and laboratory investigations of 40 APDS patients were reviewed. Patients were contacted via phone call to follow up their current situation. RESULTS: Sinopulmonary infections and lymphoproliferation were the most common complications in this cohort. Three (10.3%) and five (12.5%) patients suffered localized BCG-induced granulomatous inflammation and tuberculosis infection, respectively. Twenty-seven patients (67.5%) were affected by autoimmunity, while malignancy (7.5%) was relatively rare to be seen. Most patients in our cohort took a combined treatment of anti-infection prophylaxis, immunoglobulin replacement, and immunosuppressive therapy such as glucocorticoid or rapamycin administration. Twelve patients underwent hematopoietic stem cell transplantation (HSCT) and had a satisfying prognosis. CONCLUSION: Clinical spectrum of APDS is heterogeneous. This cohort's high incidence of localized BCG-induced granulomatous inflammation and tuberculosis indicates Mycobacterial susceptibility in APDS patients. Rapamycin is effective in improving lymphoproliferation and cytopenia. HSCT is an option for those who have severe complications and poor response to other treatments.

Research Note: Rapid generation of a novel fowl adenovirus serotype 11 reverse genetic platform.

Fowl adenovirus serotype 11 (FAdV-11) is one of the main causative agents of inclusion body hepatitis (IBH) in broilers. Outbreaks of FAdV-11-related IBH have been increasingly reported in China and many other geographical areas worldwide. However, the critical virulence factors of FAdV-11 remain uncertain due to the lack of technical platforms for efficient manipulation of FAdV-11 genome. Here, we reported the establishment of a FAdV-11 reverse genetic system based on a novel FAdV-11 Chinese isolate FJSW/2021 using the exonuclease combined with RecET (ExoCET), Redαß recombineering and ccdB counter-selection techniques for the first time. A recombinant FAdV-11 was rescued efficiently by using the established reverse genetic platform through swapping the ORF11 gene of the FAdV-11 FJSW/2021 with the ZsGreen fluorescent protein expression cassette. This study provides an effective technical platform for identifying virulence factors of FAdV-11 and developing recombinant FAdV-11-vectored vaccine candidates.

Genome characterization of a novel fowl adenovirus serotype 8b isolate and construction of the reverse genetic system for rapid genome manipulation.

Inclusion body hepatitis (IBH) induced by fowl adenovirus serotype 8b (FAdV-8b) infection is an important avian infectious disease circulating around the globe, posing significant losses to the poultry industry. In this study, a FAdV-8b strain, CH/SDQD/2021, was isolated from IBH-affected chickens in Shandong province, China and the genetic properties of CH/SDQD/2021 were characterized. The full genome length of CH/SDQD/2021 is 44,000 bp, with a G+C content of 58 % and 32 open reading frames (ORF). Sequencing alignment and phylogenetic analysis indicated that the genome identity of CH/SDQD/2021 compared to 30 other FAdV-E strains retrieved from GenBank ranges from 89.72 % to 96.71 %. Animal regression test indicated that CH/SDQD/2021 infection induced IBH in one-week-old SPF chickens. Subsequently, a reverse genetic system was developed to facilitate rapid genome manipulation of FAdV-8b for gene function study and vaccine development. To explore potential foreign gene insertion sites in FAdV-8b, ORF0-1-2, ORF11 and ORF19 of CH/SDQD/2021 were substituted by the green fluorescent gene ZsGreen, respectively, and the corresponding recombinant viruses were successfully rescued. The results showed that comparing with the parental FAdV-8b, the replication efficiency of the ORF0-1-2-substituted recombinant was reduced, while the replication efficiency of the ORF11-substituted recombinant was promoted. The findings of this study enrich the epidemiological data for the prevalent FAdV strains in China. Furthermore, the establishment of the FAdV-8b reverse genetic system will provide an efficient technique platform for FAdV-8b gene function research at the whole virus level and developing related multivalent vaccine candidates.

The prevalence of microsporidia in China : A systematic review and meta-analysis.

Microsporidia are a diverse parasite phylum infecting host from all major taxa in all global biomes. This research was conducted to conclude the prevalence of microsporidia in China. All published articles up to February 16, 2018 were considered, including descriptive, cross-sectional, case-control and epidemiology studies. A total of 1052 articles were separated after literature search. After a strict selection according to our criteria, 82 articles were included in qualitative synthesis and ultimately 52 studies were included in quantitative synthesis. Three species of microsporidia were confirmed to exist in China, including Enterocytozoon bieneusi (E. bieneusi), Nosema and Encephalitozoon cuniculi (E. cuniculi). The highest overall estimated prevalence of E. bieneusi in humans was 8.1%, which was observed in acquired immunodeficiency syndrome patients (AIDS). Moreover, the prevalence of E. bieneusi in animals including the cattle, dogs, pigs, deer, sheep and goats were analyszed in this study. The overall estimated prevalence of E. bieneusi acquired by using the random effects model in meta-analysis in cattle, dogs, pigs, sheep and goats and deer was 20.0% (95% confidence intervals: 0.133-0.266, I2 = 98.031%, p < 0.0001), 7.8% (95% CI: 0.050-0.106, I2 = 60.822%, p = 0.0537), 45.1% (95% CI: 0.227-0.674, I2 = 98.183%, p < 0.0001), 28.1% (95% CI: 0.146-0.415, I2 = 98.716%, p < 0.0001) and 19.3% (95% CI: 0.084-0.303, I2 = 96.995%, p < 0.0001) respectively. The overall detection rate of E. bieneusi in water acquired by using the random effects model in meta-analysis was 64.5% (95% CI: 0.433-0.857, I2 = 98.486%, p < 0.0001). Currently, 221 genotypes of E. bieneusi, 1 genotype of E. cuniculi and 6 Nosema were detected in China. The most prevalent genotype of E. bieneusi was genotype D, followed by BEB6 and EbpC.

Author Correction: The prevalence of microsporidia in China: A systematic review and meta-analysis.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.