Clinical analysis of PAFAH1B1 gene variants in pediatric patients with epilepsy.

PURPOSE: PAFAH1B1, also known as LIS1, is associated with type I lissencephaly in humans, which is a severe developmental brain disorder believed to result from abnormal neuronal migration. Our objective was to characterize the genotypes and phenotypes of PAFAH1B1-related epilepsy. METHODS: We conducted a comprehensive analysis of the medical histories, magnetic resonance imaging findings, and video-electroencephalogram recordings of 11 patients with PAFAH1B1 variants at the Neurology Department of Beijing Children's Hospital from June 2017 to November 2022. RESULTS: The age of onset of epilepsy ranged from 2 months to 4 years, with a median onset age of 5 months. Among these 11 patients (comprising 6 boys and 5 girls), all were diagnosed with lissencephaly type 1. Predominantly, generalized tonic-clonic and spasm seizures characterized PAFAH1B1-related epilepsy. Additionally, 10 out of the 11 patients exhibited severe developmental disorders. All patients exhibited de novo variants, with three individuals displaying 17p13.3 deletions linked to haploinsufficiency of PAFAH1B1. Four variants were previously unreported. Notably, three patients with 17p13.3 deletions displayed developmental delay and drug resistant epilepsy, whereas the single patient with mild developmental delay, Intelligence Quotient (IQ) 57 and well-controlled seizures had a splicing-site variant. CONCLUSION: The severity of the phenotype in patients with PAFAH1B1 variants ranged from drug-responsive seizures to severe epileptic encephalopathy. These observations underscore the clinical heterogeneity of PAFAH1B1-related disorders, with most patients exhibiting developmental disorders. Moreover, the severity of epilepsy appears to be linked to genetic variations.

RAP80 phase separation at DNA double-strand break promotes BRCA1 recruitment.

RAP80 has been characterized as a component of the BRCA1-A complex and is responsible for the recruitment of BRCA1 to DNA double-strand breaks (DSBs). However, we and others found that the recruitment of RAP80 and BRCA1 were not absolutely temporally synchronized, indicating that other mechanisms, apart from physical interaction, might be implicated. Recently, liquid-liquid phase separation (LLPS) has been characterized as a novel mechanism for the organization of key signaling molecules to drive their particular cellular functions. Here, we characterized that RAP80 LLPS at DSB was required for RAP80-mediated BRCA1 recruitment. Both cellular and in vitro experiments showed that RAP80 phase separated at DSB, which was ascribed to a highly disordered region (IDR) at its N-terminal. Meanwhile, the Lys63-linked poly-ubiquitin chains that quickly formed after DSBs occur, strongly enhanced RAP80 phase separation and were responsible for the induction of RAP80 condensation at the DSB site. Most importantly, abolishing the condensation of RAP80 significantly suppressed the formation of BRCA1 foci, encovering a pivotal role of RAP80 condensates in BRCA1 recruitment and radiosensitivity. Together, our study disclosed a new mechanism underlying RAP80-mediated BRCA1 recruitment, which provided new insight into the role of phase separation in DSB repair.

[Heat-sensitive moxibustion for migraine without aura: a randomized controlled trial].

OBJECTIVE: To compare the clinical effect between heat-sensitive moxibustion and mild moxibustion for migraine without aura. METHODS: A total of 54 patients with migraine without aura were randomized into an observation group (27 cases, 2 cases dropped off) and a control group (27 cases, 2 cases dropped off). The basic western medication treatment was adopted in the two groups. In the control group, mild moxibustion was applied at Shuaigu (GB 8), Fengchi (GB 20) and Yanglingquan (GB 34) on the affected side. In the observation group, the frequent acupoint areas of the affected side i.e. Shuaigu (GB 8), Fengchi (GB 20), Taiyang (EX-HN 5), Taichong (LR 3), Yanglingquan (GB 34) were determined, 3 acupoints with strong heat-sensitive sensation were selected each time and mild moxibustion was adopted. The treatment was given once a day, 5 times of treatment was as one course and 2 courses were required in the two groups. Before and after treatment, the scores of migraine symptom, visual analogue scale (VAS), migraine specific quality of life questionnaire (MSQ) were observed, and the clinical efficacy was evaluated after treatment in the two groups. RESULTS: After treatment, the scores of migraine symptom and VAS were decreased compared with those before treatment (P<0.01), while the MSQ scores were increased compared with those before treatment (P<0.01) in the two groups. After treatment, the scores of migraine symptom and VAS in the observation group were lower than those in the control group (P<0.05), while the MSQ score in the observation group was higher than that in the control group (P<0.01). The total effective rate was 92.0% (23/25) in the observation group, which was superior to 72.0% (18/25) in the control group (P<0.05). CONCLUSION: Both heat-sensitive moxibustion and mild moxibustion can effectively alleviate the clinical symptoms, improve the headache degree and life quality in patients with migraine without aura, the clinical efficacy of heat-sensitive moxibustion is superior to that of mild moxibustion.

[Effect of acupuncture on swallowing function for patients of Parkinson's disease with dysphagia].

OBJECTIVE: To observe the effects of acupuncture on swallowing function and quality of life for patients with dysphagia in Parkinson's disease (PD). METHODS: A total of 60 patients of PD with dysphagia were randomly divided into an observation group (30 cases, 2 cases dropped off) and a control group (30 cases, 3 cases dropped off). The control group was given conventional medication therapy and rehabilitation training. On the basis of the treatment as the control group, the observation group was given acupuncture at Fengfu (GV 16), Baihui (GV 20), Shenting (GV 24), Yintang (GV 24+), Yansanzhen and bilateral Fengchi (GB 20), 30 min each time, once a day, 6 times a week for 4 weeks. Before and after treatment, the Kubota water swallowing test, standardized swallowing assessment (SSA) and swallowing quality of life (SWAL-QOL) were used to evaluate the swallowing function and quality of life of the two groups. RESULTS: After treatment, the Kubota water swallowing test grade, SSA scores in the two groups were decreased compared with those before treatment (P<0.05, P<0.001)，the SWAL-QOL scores were increased compared with those before treatment (P<0.001); in the observation group，the Kubota water swallowing test grade and SSA score were lower than those in the control group (P<0.05)，the SWAL-QOL score was higher than that in the control group (P<0.001). CONCLUSION: On the basis of conventional medication therapy and rehabilitation training，acupuncture could improve the swallowing function and quality of life for patients of PD with dysphagia.

[Effects of moxibustion on serum levels of ß-EP, SP and expression of IL-1ß and COX-2 protein in brainstem in rats with migraine].

OBJECTIVE: To observe the effects of moxibustion at "Baihui" (GV 20) and "Dazhui" (GV 14) at different time points on the serum level of ß-endorphin (ß-EP), substance P (SP) and expression of interleukin-1ß (IL-1ß) and cyclooxygenase-2 (COX-2) protein in brainstem in rats with migraine, and to explore the effect and mechanism of moxibustion in preventing and treating migraine. METHODS: Forty male SD rats were randomly divided into a blank group, a model group, a prevention+treatment (PT) group and a treatment group, 10 rats in each group. Except the blank group, the rats in the remaining groups were injected with nitroglycerin subcutaneously to prepare migraine model. The rats in the PT group were treated with moxibustion 7 days before modeling (once a day) and 30 min after modeling, while the rats in the treatment group were treated with moxibustion 30 min after modeling. The "Baihui" (GV 20) and "Dazhui" (GV 14) were taken for 30 minutes each time. The behavioral scores in each group were observed before and after modeling. After intervention, ELISA method was used to detect the serum level of ß-EP and SP; the immunohistochemistry method was used to detect the number of positive cells of IL-1ß in brainstem; the Western blot method was used to detect the expression of COX-2 protein in brainstem. RESULTS: Compared with the blank group, the behavioral scores in the model group were increased 0-30 min, 60-90 min and 90-120 min after modeling (P<0.01); compared with the model group, in the treatment group and the PT group, the behavioral scores were decreased 60-90 min and 90-120 min after modeling (P<0.01). Compared with the blank group, in the model group, the serum level of ß-EP was decreased (P<0.01), while the serum level of SP, the number of positive cells of IL-1ß in brainstem and the expression of COX-2 protein were increased (P<0.01). Compared with the model group, in the PT group and and the treatment group, the serum level of ß-EP was increased (P<0.01), while the serum level of SP, the number of positive cells of IL-1ß and the expression of COX-2 protein in brainstem were decreased (P<0.01, P<0.05). Compared with the treatment group, in the PT group, the serum level of ß-EP was increased and COX-2 protein expression was decreased (P<0.05). CONCLUSION: Moxibustion could effectively relieve migraine. The mechanism may be related to reduce the serum level of SP, IL-1ß and COX-2 protein expression in brainstem, and increase the serum level of ß-EP, and the optimal effect is observed in the PT group.

NOP53 undergoes liquid-liquid phase separation and promotes tumor radio-resistance.

Aberrant DNA damage response (DDR) axis remains the major molecular mechanism for tumor radio-resistance. We recently characterized liquid-liquid phase separation (LLPS) as an essential mechanism of DDR, and identified several key DDR factors as potential LLPS proteins, including nucleolar protein NOP53. In this study, we found that NOP53 formed highly concentrated droplets in vivo and in vitro, which had liquid-like properties including the fusion of adjacent condensates, rapid fluorescence recovery after photobleaching and the sensitivity to 1,6-hexanediol. Moreover, the intrinsically disordered region 1 (IDR1) is required for NOP53 phase separation. In addition, multivalent-arginine-rich linear motifs (M-R motifs), which are enriched in NOP53, were essential for its nucleolar localization, but were dispensable for the LLPS of NOP53. Functionally, NOP53 silencing diminished tumor cell growth, and significantly sensitized colorectal cancer (CRC) cells to radiotherapy. Mechanically, NOP53 negatively regulated p53 pathway in CRC cells treated with or without radiation. Importantly, data from clinical samples confirmed a correlation between NOP53 expression and tumor radio-resistance. Together, these results indicate an important role of NOP53 in radio-resistance, and provide a potential target for tumor radio-sensitization.

Expression Pattern and Prognostic Value of CTLA-4, CD86, and Tumor-Infiltrating Lymphocytes in Rectal Cancer after Neoadjuvant Chemo(radio)therapy.

The synergistic effect of combining immune checkpoint inhibitors (ICIs) with neoadjuvant chemo(radio)therapy (nCRT) in colorectal cancer is still limited. We aimed to understand the impact of nCRT on the tumor microenvironment and to explore favorable immune markers of this combination. Herein, we investigated the expression of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), CD86, CD4, and CD8 after nCRT and its association with clinicopathological characteristics. Immunostaining of immune-related molecules was performed in 255 surgically resected specimens from rectal cancer patients treated with nCRT. CD4 and CD8 expression on the tumor (tCD4/CD8), stroma (sCD4/CD8), and invasive front (iCD4/CD8) was evaluated. The expression levels of immune-related molecules were significantly lower in the nCRT-treated group, except for CTLA-4 and sCD8. However, patients with higher sCD8+ cell density and CTLA-4 expression had better progression-free survival (PFS) and distant metastasis-free survival (DMFS). In addition, higher CD86 expression was associated with poorer overall survival (OS). Higher CTLA-4 expression was associated with higher tCD8+ cell density, whereas CD86 expression was correlated with the cell density of t/sCD8. Prognostic analysis confirmed that the relationships between CTLA-4 and DMFS as well as CD86 and OS were significantly correlated in low rather than high CD8+ cell density. Further the combination of CD8+ cell density and CD86 expression was shown to be an independent prognostic factor of OS, whereas the combination of CTLA-4 was not for DMFS. Together, these results demonstrate significant correlations between CD86 expression and t/sCD8+ cell density in rectal cancer after nCRT and could potentially have clinical implications for combining ICIs and nCRT.

DNA damage-induced paraspeckle formation enhances DNA repair and tumor radioresistance by recruiting ribosomal protein P0.

Paraspeckles are mammal-specific membraneless nuclear bodies that participate in various biological processes. NONO, a central paraspeckle component, has been shown to play pivotal roles in DNA double-strand breaks (DSB) repair, whereas its underlying mechanism needs to be further disclosed. Here, using co-immunoprecipitation and mass spectrum, we identified ribosomal protein P0 (RPLP0) as a DSB-induced NONO-binding protein; RPLP0 binds to the RRM1 and RRM2 domains of NONO. Similar to NONO, RPLP0 enhances non-homologous end joining-mediated DSB repair, which was ascribed to a ribosome-independent manner. Interestingly, paraspeckles were induced as early as 15 min after irradiation; it further recruited nuclear RPLP0 to enhance its interaction with NONO. Radiation-induced NONO/RPLP0 complex subsequently anchored at the damaged DNA and increased the autophosphorylation of DNA-PK at Thr2609, thereby enhancing DSB repair. Consistently, in vivo and in vitro experiments showed that depletion of NONO sensitizes tumor cells to radiation. For patients with locally advanced rectal cancer, NONO expression was remarkably increased in tumor tissues and correlated with a poor response to radiochemotherapy. Our findings suggest a pivotal role of radiation-induced paraspeckles in DNA repair and tumor radioresistance, and provide a new insight into the ribosome-independent function of ribosomal proteins.

MRNIP condensates promote DNA double-strand break sensing and end resection.

The rapid recognition of DNA double-strand breaks (DSBs) by the MRE11/RAD50/NBS1 (MRN) complex is critical for the initiation of DNA damage response and DSB end resection. Here, we show that MRN complex interacting protein (MRNIP) forms liquid-like condensates to promote homologous recombination-mediated DSB repair. The intrinsically disordered region is essential for MRNIP condensate formation. Mechanically, the MRN complex is compartmentalized and concentrated into MRNIP condensates in the nucleus. After DSB formation, MRNIP condensates move to the damaged DNA rapidly to accelerate the binding of DSB by the concentrated MRN complex, therefore inducing the autophosphorylation of ATM and subsequent activation of DNA damage response signaling. Meanwhile, MRNIP condensates-enhanced MRN complex loading further promotes DSB end resection. In addition, data from xenograft models and clinical samples confirm a correlation between MRNIP and radioresistance. Together, these results reveal an important role of MRNIP phase separation in DSB response and the MRN complex-mediated DSB end resection.

Polyketone metabolites isolated from Rhodiola tibetica endohytic fungus Alternaria sp. HJT-Y7 and their SARS-CoV-2 virus inhibitory activitives.

Six new polyketone metabolites, compounds (1-6) and seven known polyketone compounds (7-13) were isolated from Rhodiola tibetica endophytic fungus Alternaria sp. The structural elucidation of five new polyketone metabolites were elucidated on the basis of spectroscopic including 2D NMR and HRMS and spectrometric analysis. Inhibition rate evaluation revealed that compounds 1(EC50 = 0.02 mM), 3(EC50 = 0.3 mM), 6(EC50 = 0.07 mM), 8(EC50 = 0.1 mM) and 9(EC50 = 0.04 mM) had inhibitory effect on the SARS-CoV-2 virus.

NONO phase separation enhances DNA damage repair by accelerating nuclear EGFR-induced DNA-PK activation.

Radioresistance is one of the main causes of cancer treatment failure, which leads to relapse and inferior survival outcome of cancer patients. Liquid-liquid phase separation (LLPS) of proteins is known to be involved in various biological processes, whereas its role in the regulation of radiosensitivity remains largely unknown. In this study, we characterized NONO, an RNA/DNA binding protein with LLPS capacity, as an essential regulator of tumor radioresistance. In vitro assay showed that NONO involved in DNA repair via non-homologous end joining (NHEJ) manner. NONO knockout significantly reduced DNA damage repair and sensitized tumor cells to irradiation in vitro and in vivo. NONO overexpression was correlated with an inferior survival outcome in cancer patients. Mechanically, NONO was associated with nuclear EGFR (nEGFR). Both irradiation and EGF treatment induced nEGFR accumulation, thereby increased the association between NONO and nEGFR. However, NONO was not a substrate of EGFR kinase. Furthermore, NONO promoted DNA damage-induced DNA-PK phosphorylation at T2609 by enhancing the interaction between EGFR and DNA-PK. Importantly, NONO protein formed high concentration LLPS droplets in vitro, and recruited EGFR and DNA-PK. Disruption of NONO droplets with LLPS inhibitor significantly reduced the interaction between EGFR and DNA-PK, and suppressed DNA damage-induced phosphorylation of T2609-DNA-PK. Taken together, LLPS of NONO recruits nuclear EGFR and DNA-PK and enhances their interaction, further increases DNA damage-activated pT2609-DNA-PK and promotes NHEJ-mediated DNA repair, finally leads to tumor radioresistance. NONO phase separation-mediated radioresistance may serve as a novel molecular target to sensitize tumor cell to radiotherapy.

Case Report: A Variant Non-ketotic Hyperglycinemia With GLRX5 Mutations: Manifestation of Deficiency of Activities of the Respiratory Chain Enzymes.

Objective: Variant non-ketotic hyperglycinaemia (NKH) is a rare disorder characterized by variable clinical, biochemical, and imaging features. The variant form of NKH is rare and characterized by variable clinical, biochemical and imaging features. Subjects: Herein, we report a girl with variant NKH with two mutations in glutaredoxin 5 (GLRX5), which has been described in only three patients. Results: The clinical and biochemical phenotypes of the patient are also described. She suffered from developmental regression associated with spasticity, developmental delay, anemia and optic atrophy. The mitochondrial leukoencephalopathy was used to designate these disorders. An increased T2 signal from the medulla oblongata to the C6 spinal region was also observed on spinal cord MRI. Tandem mass analysis of a dried blood sample revealed elevated levels of glycine. The patient has two compound heterozygous mutations (c.151_153 del AAG and c.196C>T) in the GLRX5 gene. The c.196C>T mutation led to a stop codon (p.Q66Ter). Activities of mitochondrial respiratory chain (MRC) complexes II+III in the patient's fibroblasts were abnormal. Conclusions: We present the case of a girl with variant NKH who manifested spasticity and bilateral cavitating leukoencephalopathy. The patient had a deficiency of a respiratory chain enzyme, and this is the first report. Genetic testing is important for physicians to evaluate suspected variant NKH patients and to provide proper genetic counseling.

PRMT1 enhances oncogenic arginine methylation of NONO in colorectal cancer.

Arginine methylation is an important posttranslational modification catalyzed by protein arginine methyltransferases (PRMTs). However, the role of PRMTs in colorectal cancer (CRC) progression is not well understood. Here we report that non-POU domain-containing octamer-binding protein (NONO) is overexpressed in CRC tissue and is a potential marker for poor prognosis in CRC patients. NONO silencing resulted in decreased proliferation, migration, and invasion of CRC cells, whereas overexpression had the opposite effect. In a xenograft model, tumors derived from NONO-deficient CRC cells were smaller than those derived from wild-type (WT) cells, and PRMT1 inhibition blocked CRC xenograft progression. A mass spectrometry analysis indicated that NONO is a substrate of PRMT1. R251 of NONO was asymmetrically dimethylated by PRMT1 in vitro and in vivo. Compared to NONO WT cells, NONO R251K mutant-expressing CRC cells showed reduced proliferation, migration, and invasion, and PRMT1 knockdown or pharmacological inhibition abrogated the malignant phenotype associated with NONO asymmetric dimethylation in both KRAS WT and mutant CRC cells. Compared to adjacent normal tissue, PRMT1 was highly expressed in the CRC zone in clinical specimens, which was correlated with poor overall survival in patients with locally advanced CRC. These results demonstrate that PRMT1-mediated methylation of NONO at R251 promotes CRC growth and metastasis, and suggest that PRMT1 inhibition may be an effective therapeutic strategy for CRC treatment regardless of KRAS mutation status.

Neurologic Manifestations as Initial Clinical Presentation of Familial Hemophagocytic Lymphohistiocytosis Type2 Due to PRF1 Mutation in Chinese Pediatric Patients.

Familial hemophagocytic lymphohistiocytosis Type 2 (FHL2) associated central nervous system (CNS) involvement is less understood in children, especially when considering neurologic manifestations as part of the initial presentation. We conducted a retrospective review of the clinical manifestations and genetic abnormality of four Han Chinese children with FHL2 who were patients at the neurology department of Beijing Children's Hospital from November 2015 to October 2018. These four patients initially manifested CNS symptoms in their disease presentation, and all four patients were misdiagnosed as having ademyelinating disease, such as acute disseminated encephalomyelitis and multiple sclerosis. Given these misdiagnoses, it is important that general physicians and pediatricians maintain awareness of the possibility of FHL2 as a differential diagnosis. These four cases included neurologic manifestations including seizures, ataxia, spasticity, gait disorder, and coma. Bilateral abnormal signals in the cerebrum, including in white matter, gray matter, and junctions were discovered. Enhanced magnetic resonance imaging (MRI) in these patients showed spot or ring enhancement and/or hemorrhage. These patients all possessed a compound heterozygote mutation PRF1 gene. Whole exome sequencing analysis revealed seven different mutations (three novel mutations) spread over the PRF1 gene and a heterozygous missense mutation c.1349C > T [p.T450M] that was present in two patients. Three novel mutations, c.634T > C[p.Y212H], c.1083_1094del[p.361_364del], and c.1306G > T [p.D436Y], were discovered and through in silico analysis were discovered to be deleterious. Neurologic manifestations were the initial symptoms of FHL2 in these patients in addition to the expected leukopenia and hepatosplenomegaly. Whole exome sequencing of PRF1 for patients with similar presentations would facilitate prompt and accurate diagnosis and treatment.

Impact of Cold Ischemic Time and Freeze-Thaw Cycles on RNA, DNA and Protein Quality in Colorectal Cancer Tissues Biobanking.

Tissue-derived RNA, DNA and protein samples become more and more crucial for molecular detection in clinical research, personalized and targeted cancer therapy. This study evaluated how to biobanking colorectal tissues through examining the influences of cold ischemic time and freeze-thaw cycles on RNA, DNA and protein integrity. Here, 144 pairs of tumor and normal colorectal tissues were used to investigate the impact of cold ischemic times (0-48h) on RNA, DNA and protein integrity at on ice or room temperature conditions. Additionally, 45 pairs of tissues experienced 0-9 freeze-thaw cycles, and then the RNA, DNA and protein quality were analyzed. On ice, RNA, DNA and protein from colorectal tumor and normal tissues were all stable up to 48h after surgery. At room temperature, RNA in colorectal tumor and normal tissues began to degrade at 8h and 24h, respectively. Meanwhile, the tumor tissues DNA degradation occurred at 24h after surgery at room temperature. Similarly, the protein expression level of tumor and normal tissues began to change at 24h after the surgery at room temperature. Interestingly, tissue RNA and DNA remained stable even after 9 freeze-thaw cycles, whereas the proteins levels were remarkably changed after 7 freeze-thaw cycles. This study provided a useful evidence on how to store human colorectal tissues for biobanking. Preserving the surgical colorectal tissue on ice was an effective way to prevent RNA, DNA and protein degradation. Importantly, more than 7 repeated freeze-thaw cycles were not recommended for colorectal tissues.

A functional promoter polymorphism of IFITM3 is associated with susceptibility to pediatric tuberculosis in Han Chinese population.

A susceptibility locus for tuberculosis, a re-emerging infectious disease throughout the world, was previously discovered to exist on chromosome 11p15. IFITM3 gene encoding for interferon inducible transmembrane protein 3, is located at 11p15. It acts as an effector molecule for interferon-gamma, which is essential for anti-tuberculosis immune response. In order to investigate the association between susceptibility to TB and genetic polymorphisms of the IFITM3 core promoter, a case-control study including 368 TB patients and 794 healthy controls was performed in Han Chinese children in northern China. The rs3888188 polymorphism showed significant association with susceptibility to TB. The rs3888188 G allele, acting recessively, was more frequent in TB patients (95% confidence interval: 1.08-1.56, Bonferroni P-value: 0.039). We further assessed the effect of rs3888188 polymorphism on IFITM3 transcription in vitro. As based on luciferase promoter assays, the promoter activity of haplotypes with rs3888188 G allele was lower than that of haplotypes with rs3888188 T allele. Moreover, peripheral-blood mononuclear cells carrying rs3888188 GG genotype showed a reduced IFITM3 mRNA level compared to cells carrying TT or GT genotype. In conclusion, rs3888188, a functional promoter polymorphism of IFITM3, was identified to influence the risk for pediatric TB in Han Chinese population.

IFNG polymorphisms are associated with tuberculosis in Han Chinese pediatric female population.

Host genetic factors play a major role in determining differential susceptibility to human tuberculosis (TB), a re-emerging infectious disease throughout the world. Genetic variations in the IFNG gene coding for interferon gamma (IFN-γ), have been identified in TB patients. To investigate the association of the IFNG polymorphisms with TB susceptibility in Chinese pediatric population. A case-control study of 189 TB patients and 164 controls was performed using single-nucleotide polymorphism (SNP) analysis. Genomic DNA was extracted from leukocytes in peripheral blood. Three SNPs of IFNG, including -1616C/T (rs2069705), +874A/T (rs2430561), and +3234C/T (rs2069718), were selected for genotyping and analysis. The +874A and +3234C alleles were more frequent among TB patients (P = 0.108 and P = 0.088), especially in females (both P = 0.029), although this difference was not significant since Bonferroni corrected significance threshold was 0.025 (two of three SNPs were found to be in linkage disequilibrium). More pronounced differences for the +874 and +3234 polymorphisms were found under the genotype comparison between TB cases and controls in the total population [P = 0.026 (borderline non-significance) and P = 0.020, respectively], and in the female subgroup (P = 0.020 and P = 0.020). The dominant model of inheritance was shown to be significant for +874A and +3234C alleles (both P = 0.019) in the female subgroup. The +874A and +3234C alleles were more frequently found in extrapulmonary TB patients than in controls (P = 0.039). Haplotype analysis carried out on these three SNPs showed the TTT haplotype to be more frequent in controls than in TB cases, and this difference showed a strong significance (P = 0.005). The +874A and +3234C alleles may be related to TB susceptibility in the female subgroup in the Chinese pediatric population of North China. The higher rate of +874A (known to correlate with lower IFN-γ expression) in the extrapulmonary TB subgroup suggests a sufficient IFN-γ expression to be not only an important factor for the onset of TB disease but also for limiting its dissemination to lungs.

ALOX5 is associated with tuberculosis in a subset of the pediatric population of North China.

BACKGROUND: Genetic factors are involved in the etiology of Mycobacterium tuberculosis infection. Recently, ALOX5 has been identified as a candidate gene for tuberculosis (TB) susceptibility. We investigated whether an association between ALOX5 and TB exists in a Chinese pediatric population from northern China. METHODS: We conducted a case-control study comprising 488 individuals aged 2 months to 17 years by genotyping 18 tag-single-nucleotide polymorphisms (SNPs) from the ALOX5 gene. The tag-SNPs were selected from the international HapMap project. An Illumina BeadXpress Scanner was utilized for genotyping, supported by the high-density BeadArray technology in combination with an allele-specific extension, adapter ligation, and amplification assay. Statistical analyses were performed to determine correlations between genetic variation and disease. RESULTS: Our study is the first to show that ALOX5 is associated with susceptibility to pediatric TB in a subset of children in northern China. The rs2115819 T allele of ALOX5 presents a risk factor for childhood TB disease.

Functional polymorphisms in CYP2C19 & CYP3A5 genes associated with decreased susceptibility for paediatric tuberculosis.

BACKGROUND & OBJECTIVES: Tuberculosis (TB) bacilli ingested by macrophages evade host immune responses by multiple mechanisms including the inhibition of apoptosis. As the cytochrome-P-450 system (CYP) contributes to apoptosis it has been suggested that genetic variation in CYP may be associated with susceptibility to TB infection. This study was carried out to evaluate cytochrome P-450 polymorphisms in Chinese Han children and to investigate the effect of these polymorphisms in paediatric TB. METHODS: Frequencies for the CYP2C19, CYP3A4, CYP3A5 and CYP2E1 mutated alleles and genotypes were compared between 142 Chinese paediatric TB patients and 150 non-infected controls by real time PCR genotyping on peripheral leukocyte DNA. RESULTS: CYP2C19 (636 G>A, rs4986893) A allele and AG genotype were associated with decreased susceptibility to TB (P = 0.006, OR= 0.33, 95% CI: 0.15-0.76; and P = 0.005, OR =0.31, 95% CI: 0.14-0.72 respectively), as were the CYP3A5 (6986A>G, rs776746) G allele and particularly homozygous GG (recessive mode) genotype (P = 0.004, OR=0.61, 95% CI: 0.43-0.85; and P=0.002, OR=0.47, 95% CI: 0.29-0.76). INTERPRETATION & CONCLUSIONS: The data suggested that CYP2C19 and CYP3A5 polymorphisms affect susceptibility to paediatric TB. Further studies are indicated to confirm and elucidate these observations.

Association of immunophenotypic characterization of peripheral lymphocytes with different clinical phenotypes of tuberculosis in Chinese Han children.

BACKGROUND: Very few researchers have studied the changes in peripheral lymphocyte patterns in adult tuberculosis (TB) and even less researches have been conducted in pediatric TB. In this study, we obtained blood samples from 114 Chinese pediatric TB patients and 116 matched controls to study the association of phenotypic subsets of peripheral lymphocytes with different clinical phenotypes of TB. METHODS: The subjects were classified as the control group and the TB patients group which were further divided into a pulmonary TB group and an extra-pulmonary TB group (more serious than the former). The distribution of lymphocyte subpopulations, including T lymphocytes, CD4(+) T lymphocytes, CD8(+) T lymphocytes, B lymphocytes, and natural killer (NK) cells, were quantitatively analyzed by flow cytometry. RESULTS: Compared to the healthy controls, TB infection was associated with significantly higher B cell (P < 0.0001), and lower T cell (P = 0.029) and NK cell (P < 0.0001) percentages. Compared to pulmonary TB patients, extra-pulmonary TB was associated with relatively higher B cell (P = 0.073), and lower T cell percentages (P = 0.021), higher purified protein derivative (PPD) negative rate (P = 0.061), and poorer PPD response (P = 0.010). Most pulmonary TB cases were primary pulmonary TB (89.1%), and most extra-pulmonary TB cases had TB meningitis (72.1%). CONCLUSIONS: This study demonstrates changes in the lymhocyte distribution in children suffering from different clinical phenotypes of TB; such as primary pulmonary TB, and TB meningitis. These patterns may have significance in understanding the pathogenesis and prognostic markers of the disease, and for developing immunomodulatory modalities of therapy.