Early screening to identify and diagnose primary nasal tuberculosis in patients with tumor necrosis factor inhibitors

In this editorial,we comment on the article by Liu et al.Based on our analysis of a case report,we consider that early screening and recognition of primary nasal tuberculosis are crucial for patients undergoing treatment with tumor necrosis factor inhibitor(TNFi).While TNFi therapy increases the risk of reactivating latent tuberculosis,primary nasal tuberculosis remains rare due to the protective mechanisms of the nasal mucosa.Risk factors for primary nasal tuberculosis include minimally invasive nasal surgery,diabetes,and human immunodefi ciency virus.Patients with early symptoms such as nasal congestion,rhinorrhea,altered olfaction,epistaxis,or ulceration,and unresponsive to conventional antibiotics and antihistamines should undergo early rhinoscopy,possibly followed by repeated tissue biopsies and acid-fast bacilli culture when necessary.When diagnosis is challenging,it is essential to consider local tuberculosis epidemiology and the efficacy of diagnostic antituberculosis treatment.The preferred method for tuberculosis screening is the Interferon Gamma Release Assay,with a general recommendation for screening at 3 and 6 months after initial treatment and then every six months.However,the optimal frequency is not yet consensus-driven and may be increased in economically viable settings.

Study of tumor necrosis factor receptor in the inflammatory bowel disease

Ulcerative colitis(UC)and Crohn’s disease(CD)are part of Inflammatory Bowel Diseases(IBD)and have pathophysiological processes such as bowel necrosis and enteric neurons and enteric glial cells.In addition,the main inflammatory mediator is related to the tumor necrosis factor-alpha(TNF-α).TNF-αis a mediator of the intestinal inflammatory processes,thus being one of the main cytokines involved in the pathogenesis of IBD,however,its levels,when measured,are present in the serum of patients with IBD.In addition,TNF-αplays an important role in promoting inflammation,such as the production of interleukins(IL),for instance IL-1βand IL-6.There are two receptors for TNF as following:The tumor necrosis factor 1 receptor(TNFR1);and the tumor necrosis factor 2 receptor(TNFR2).They are involved in the pathogenesis of IBD and their receptors have been detected in IBD and their expression is correlated with disease activity.The soluble TNF form binds to the TNFR1 receptor with,and its activation results in a signaling cascade effects such as apoptosis,cell proliferation and cytokine secretion.In contrast,the transmembrane TNF form can bind both to TNFR1 and TNFR2.Recent studies have suggested that TNF-αis one of the main pro-inflammatory cytokines involved in the pathogenesis of IBD,since TNF levels are present in the serum of both patients with UC and CD.Intravenous and subcutaneous biologics targeting TNF-αhave revolutionized the treatment of IBD,thus becoming the best available agents to induce and maintain IBD remission.The application of antibodies aimed at neutralizing TNF-αin patients with IBD that induce a satisfactory clinical response in up to 60%of patients,and also induced long-term maintenance of disease remission in most patients.It has been suggested that anti-TNF-αagents inactivate the pro-inflammatory cytokine TNF-αby direct neutralization,i.e.,resulting in suppression of inflammation.However,anti-TNF-αantibodies perform more complex functions than a simple blockade.

Predictors and optimal management of tumor necrosis factor antagonist nonresponse in inflammatory bowel disease:A literature review

Tumor necrosis factor-α(TNF-α)antagonists,the first biologics approved for treating patients with inflammatory bowel disease(IBD),are effective for the induction and maintenance of remission and significantly improving prognosis.However,up to one-third of treated patients show primary nonresponse(PNR)to anti-TNF-αtherapies,and 23%-50%of IBD patients experience loss of response(LOR)to these biologics during subsequent treatment.There is still no recognized predictor for evaluating the efficacy of anti-TNF drugs.This review summarizes the existing predictors of PNR and LOR to anti-TNF in IBD patients.Most predictors remain controversial,and only previous surgical history,disease manifestations,drug concentrations,antidrug antibodies,serum albumin,some biologic markers,and some genetic markers may be potentially predictive.In addition,we also discuss the next steps of treatment for patients with PNR or LOR to TNF antagonists.Therapeutic drug monitoring plays an important role in treatment selection.Dose escalation,combination therapy,switching to a different anti-TNF drug,or switching to a biologic with a different mechanism of action can be selected based on the concentration of the drug and/or antidrug antibodies.

Joint Detection of Serum Vitamin D,Body Mass Index,and Tumor Necrosis Factor Alpha for the Diagnosis of Crohn’s Disease

Objective Vitamin D(VD)deficiency was reported to contribute to the progression of Crohn’s disease(CD)and affect the prognosis of CD patients.This study investigated the role of serum VD,body mass index(BMI),and tumor necrosis factor alpha(TNF-α)in the diagnosis of Crohn’s disease.Methods CD patients(n=76)and healthy subjects(n=76)were enrolled between May 2019 and December 2020.The serum 25-hydroxyvitamin D[25(OH)D]levels,BMI,and TNF-αlevels,together with other biochemical parameters,were assessed before treatment.The diagnostic efficacy of the single and joint detection of serum 25(OH)D,BMI,and TNF-αwas determined using receiver operating characteristic(ROC)curves.Results The levels of 25(OH)D,BMI,and nutritional indicators,including hemoglobin,total protein,albumin,and high-density lipoprotein cholesterol,were much lower,and the TNF-αlevels were much higher in the CD patients than in the healthy subjects(P<0.05 for all).The areas under the ROC curve for the single detection of 25(OH)D,BMI,and TNF-αwere 0.887,0.896,and 0.838,respectively,with the optimal cutoff values being 20.64 ng/mL,19.77 kg/m^(2),and 6.85 fmol/mL,respectively.The diagnostic efficacy of the joint detection of 25(OH)D,BMI,and TNF-αwas the highest,with an area under the ROC curve of 0.988(95%CI:0.968–1.000).Conclusion The joint detection of 25(OH)D,TNF-α,and BMI showed high sensitivity,specificity,and accuracy in CD diagnosis;thus,it would be effective for the diagnosis of CD in clinical practice.

Acute heart failure as an adverse event of tumor necrosis factor inhibitor therapy in inflammatory bowel disease:A review of the literature

Tumor necrosis factor inhibitors(anti-TNFs)are widely used therapies for the treatment of inflammatory bowel diseases(IBD);however,their administration is not risk-free.Heart failure(HF),although rare,is a potential adverse event related to administration of these medications.However,the exact mechanism of development of HF remains obscure.TNFαis found in both healthy and damaged hearts.Its effects are concentration-and receptor-dependent,promoting either cardio-protection or cardiomyocyte apoptosis.Experimental rat models with TNFαreceptor knockout showed increased survival rates,less reactive oxygen species formation,and improved diastolic left ventricle pressure.However,clinical trials employing anti-TNF therapy to treat HF had disappointing results,suggesting abolishment of the cardioprotective properties of TNFα,making cardiomyocytes susceptible to apoptosis and oxidation.Thus,patients with IBD who have risk factors should be screened for HF before initiating anti-TNF therapy.This review aims to discuss adverse events associated with the administration of anti-TNF therapy,with a focus on HF,and propose some approaches to avoid cardiac adverse events in patients with IBD.

Tumor Necrosis Factor-Alpha (TNF)-308G/A and Interleukin 8(IL-8)-251C/T Polymorphisms in Pulmonary Tuberculosis Patients from Congo

Background: Tuberculosis (TB) is one of the world’s deadliest infectious diseases. Tumor necrosis factor-Alpha (TNF-α) and Interleukin 8 (IL-8) are involved in the pathogenesis of pulmonary TB (PTB). However, the contribution of polymorphisms of these cytokines to PTB susceptibility needed more investigation across geographic regions and ethnic groups. Purpose: The aim of this study was to investigate the association of the TNF-α-308 G/A and IL-8-251T/A polymorphisms with PTB risk in the Congolese population. Methods: This case-control study included 150 PTB patients and 160 control subjects. Blood samples were collected from all participants and were used for the TNF-α-308 G/A and IL-8-251T/A genotyping by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Odds ratios (OR) were calculated to estimate the potential polymorphism associations. A P level of Results: A significant difference was found between PTB patients and controls regarding the TNF-α-308AA genotype (P = 0.035) distribution. Moreover, this genotype was associated with risk to TB (OR = 7.19, 95% CI = 0.85 - 60.65, P = 0.035). The A allele was significantly more frequent in PTB patients than in controls, and was associated with risk to PTB (OR = 1.68, 95% CI = 1.05 - 2.68, P = 0.014). Regarding the IL-8-251T/A gene, TA and AA genotypes were significantly more frequent in PTB patients compared to controls, and were associated with increased risk to PTB (OR = 2.64, 95% CI = 0.97 - 7.18, P = 0.031 and OR = 3.0, 95% CI = 1.13 - 7.98, P = 0.014, respectively). However, the IL-8-251 A allele was not associated to PTB susceptibility (OR = 0.27, 95% CI = 0.15 - 0.44). Conclusion: TNF-α-308G/A and IL-8-251T/A polymorphisms may be associated to PTB susceptibility in the Congolese population, and the AA genotype of both cytokines could be a risk factor.

Genetic associations with adverse events from anti-tumor necrosis factor therapy in inflammatory bowel disease patients

AIM To study the type and frequency of adverse events associated with anti-tumor necrosis factor(TNF)therapy and evaluate for any serologic and genetic associations.METHODS This study was a retrospective review of patients attending the inflammatory bowel disease(IBD) centers at Cedars-Sinai IBD Center from 2005-2016. Adverse events were identified via chart review. IBD serologies were measured by ELISA. DNA samples were genotyped at Cedars-Sinai using Illumina Infinium Immunochipv1 array per manufacturer's protocol. SNPs underwent methodological review and were evaluated using several SNP statistic parameters to ensure optimal allele-calling. Standard and rigorous QC criteria were applied to the genetic data, which was generated using immunochip. Genetic association was assessed by logistic regression after correcting for population structure.RESULTS Altogether we identified 1258 IBD subjects exposed to anti-TNF agents in whom Immunochip data were available. 269/1258 patients(21%) were found to have adverse events to an anti-TNF-α agent that required the therapy to be discontinued. 25% of women compared to 17% of men experienced an adverse event. All adverse events resolved after discontinuing the antiTNF agent. In total: n = 66(5%) infusion reactions; n = 49(4%) allergic/serum sickness reactions; n = 19(1.5%) lupus-like reactions, n = 52(4%) rash, n = 18(1.4%) infections. In Crohn's disease, Ig A ASCA(P = 0.04) and Ig G-ASCA(P = 0.02) levels were also lower in patients with any adverse events, and anti-I2 level in ulcerative colitis was significantly associated with infusion reactions(P = 0.008). The logistic regression/human annotation and network analyses performed on the Immunochip data implicated the following five signaling pathways: JAK-STAT(Janus Kinase-signal transducer and activator of transcription), measles, IBD, cytokine-cytokine receptor interaction, and toxoplasmosis for any adverse event. CONCLUSION Our study shows 1 in 5 IBD patients experience an adverse event to anti-TNF therapy with novel serologic, genetic, and pathways associations.

Genetic polymorphisms predict response to anti-tumor necrosis factor treatment in Crohn's disease

To investigate genetic factors that might help define which Crohn’s disease (CD) patients are likely to benefit from anti-tumor necrosis factor (TNF) therapy. METHODSThis was a prospective cohort study. Patients were recruited from a university digestive disease practice database. We included CD patients who received anti-TNF therapy, had available medical records (with information on treatment duration and efficacy) and who consented to participation. Patients with allergic reactions were excluded. Patients were grouped as ever-responders or non-responders. Genomic DNA was extracted from peripheral blood, and 7 single nucleotide polymorphisms (SNPs) were assessed. The main outcome measure (following exposure to the drug) was response to therapy. The patient genotypes were assessed as the predictors of outcome. Possible confounders and effect modifiers included age, gender, race, and socioeconomic status disease, as well as disease characteristics (such as Montreal criteria). RESULTS121 patients were included. Twenty-one were non-responders, and 100 were ever-responders. Fas ligand SNP (rs763110) genotype frequencies, TNF gene -308 SNP (rs1800629) genotype frequencies, and their combination, were significantly different between groups on multivariable analysis controlling for Montreal disease behavior and perianal disease. The odds of a patient with a Fas ligand CC genotype being a non-responder were four-fold higher as compared to a TC or TT genotype (P = 0.009, OR = 4.30, 95%CI: 1.45-12.80). The presence of the A (minor) TNF gene -308 allele correlated with three-fold higher odds of being a non-responder (P = 0.049, OR = 2.88, 95%CI: 1.01-8.22). Patients with the combination of the Fas ligand CC genotype and the TNF -308 A allele had nearly five-fold higher odds of being a non-responder (P = 0.015, OR = 4.76, 95%CI: 1.35-16.77). No difference was seen for the remaining SNPs. CONCLUSIONThe Fas-ligand SNP and TNF gene -308 SNP are associated with anti-TNF treatment response in CD and may help select patients likely to benefit from therapy.

Association between genetic variations in tumor necrosis factor receptor genes and survival of patients with T-cell lymphoma

The prognosis of T-cell lymphoma (TCL) has been shown to be associated with the clinical characteristics of patients. However, there is little knowledge of whether genetic variations also affect the prognosis of TCL. This study investigated the associations between single nucleotide polymorphisms(SNPs) in tumor necrosis factor receptor superfamily(TNFRSF) genes and the survival of patients with TCL. A total of 38 tag SNPs in 18 TNFRSF genes were genotyped using Sequenom platform in 150 patients with TCL. Kaplan-Meier survival estimates were plotted and significance was assessed using log-rank tests. Cox proportional hazard models were used to analyze each of these 38 SNPs with adjustment for covariates that might influence patient survival, including sex and international prognostic Index score. Hazard ratios (HRs) and their 95% confidence intervals(CIs) were calculated. Among the 38 SNPs tested, 3 were significantly associated with the survival of patients with TCL. These SNPs were located at LTβR (rs3759333C>T) and TNFRSF17(rs2017662C>T and rs2071336C>T). The 5-year survival rates were significantly different among patients carrying different genotypes and the HRs for death between the different genotypes ranged from 0.45 to 2.46. These findings suggest that the SNPs in TNFRSF genes might be important determinants for the survival of TCL patients.

Recombination Mutant Human Tumor Necrosis Factor Combined with Chemotherapy in the Treatment of Advanced Cancer

Objective: Past studies showed that tumor necrosis factor (TNF) assisted anti-tumor treatment and intensified the sensitivity of chemotherapy. However its clinical application has been curbed because of its low purity, high dosage, and strong toxicity. The objective of present study is to evaluate the therapeutic effects and adverse reactions of recombinant mutant human tumor necrosis factor (rmhTNF) combined with chemotherapy in patients with advanced malignant tumor. Methods: 105 patients with advanced malignant tumor were randomly divided into trial group, 69 patients, and control group, 36 patients. rmhTNF was injected intramuscularly to the trial group at a dose of 4×106 U/m2, from the 1st to 7th days, the 11th to 17th days combined with chemotherapy course. The chemotherapy plan was as follows: CAP for patients with the NSCLC; FAM for patients with gastric cancer; FC for patients with colorectal cancer. One treatment cycle lasted for 21 days and two cycles were scheduled. The control group was given only the same chemotherapy as the trial group. Results: In the trial group there was 1 CR case and 12 PR cases, and the response rate was 13/69 (18.84%); in the control group 1 PR case, the response rate 1/36 (2.78%). The response rate in the trial group was significantly higher than that in the control group (P=0.022). The response rate for NSCLC in the trial group was 8/17 (47.06%), and 1/6 (16.67%) in the control group. The response rates for gastric cancer and colorectal cancer in the trial groups also were higher than those in the control groups. After the treatment the KPS was 89.00±9.92 in the trial group, and 84.17±8.84 in the control group, with a significant difference between the two groups (P=0.028). The adverse reactions of rmhTNF injection included: pain in the injection area, chill, hardening and swelling and redness in the injection area, fever, ostealgia and myosalgia, and cold-like symptoms. All these adverse reactions were mild and bearable. Conclusion: The administration of rmhTNF in combination with general chemotherapy is an effective and secure means in treating advanced malignant tumor.

Uptake of bacterial lipopolysaccharide and expression of tumor necrosis factor α mRNA in isolated rat intrahepatic bile duct epithelial cells *

AIM To study the uptake of bacterial lipopolysaccharides (LPS) and expression of tumor necrosis factor α mRNA (TNF α mRNA) with cultured rat intrahepatic bile duct epithelial cells.

Relationship between tumor necrosis factor-α and liver fibrosis

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Influence of granulocyte-macrophage colonystimulating factor and tumor necrosis factor on anti-hepatoma activities of human dendritic cells

INTRODUCTIONDendritic cells (DCs) play a key regulatory role inantitumor immunity,especially in its immuneaccessory role via MHC-Ⅰ molecules.We haverecently reported that DCs were able to enhance thekilling activity of Lymphokine and PHA activatedkiller (LPAK) cells in vitro.In the presentstudy,we evaluated the effects of GM-CSF andTNF upon antitumor activities of freshly

Blood glucose changes surrounding initiation of tumor-necrosis factor inhibitors and conventional disease-modifying anti-rheumatic drugs in veterans with rheumatoid arthritis

AIM To determine the scope of acute hypoglycemic effects for certain anti-rheumatic medications in a large retrospective observational study. METHODS Patients enrolled in the Veterans Affairs Rheumatoid Arthritis (VARA) registry were selected who, during follow-up, initiated treatment with tumor necrosis factor inhibitors (TNFi's, including etanercept, adalimumab, infliximab, golimumab, or certolizumab), prednisone, or conventional disease-modifying anti-rheumatic drugs(DMARDs), and for whom proximate random blood glucose (RBG) measurements were available within a window 2-wk prior to, and 6 mo following, medication initiation. Similar data were obtained for patients with proximate values available for glycosylated hemoglobin A1C values within a window 2 mo preceding, and 12 mo following, medication initiation. RBG and A1C measurements were compared before and after initiation events using paired t-tests, and multivariate regression analysis was performed including established comorbidities and demographics.RESULTS Two thousands one hundred and eleven patients contributed at least one proximate measurement surrounding the initiation of any examined medication. A significant decrease in RBG was noted surrounding 653 individual hydroxychloroquine-initiation events(-3.68 mg/dL, P = 0.04), while an increase was noted for RBG surrounding 665 prednisone-initiation events(+5.85 mg/d L, P < 0.01). A statistically significant decrease in A1C was noted for sulfasalazine initiation, as measured by 49 individual initiation events(-0.70%, P < 0.01). Multivariate regression analyses, using methotrexate as the referent, suggest sulfasalazine (β =-0.58, P = 0.01) and hydroxychloroquine(β =-5.78, P = 0.01) use as predictors of lower post-medicationinitiation RBG and A1C values, respectively. Analysis by drug class suggested prednisone (or glucocorticoids) as predictive of higher medication-initiation event RBG among all start events as compared to DMARDs, while this analysis did not show any drug class-level effect for TNFi. A diagnosis of congestive heart failure(β = 4.69, P = 0.03) was predictive for higher post-initiation RBG values among all medication-initiation events.CONCLUSION No statistically significant hypoglycemic effects surrounding TNFi initiation were observed in this large cohort. Sulfasalazine and hydroxychloroquine may have epidemiologically significant acute hypoglycemic effects.

The Change of Interleukin-6 and Tumor Necrosis Factor in Patients with Obstructive Sleep Apnea Syndrome

The levels of lipopolysaccharide (LPS) induced interleukin 6 (IL 6) and tumor necrosis factor α (TNF α) expression in culture of peripheral blood mononuclear cells (PBMC) and the plasma levels of IL 6 and TNF α in the patients with obstructive sleep apnea syndrome (OSAS) were measured and the relationship between OSAS and IL 6 or TNF α expression studied. Both IL 6 and TNF α were detected by using ELISA in 22 patients with OSAS and 16 normal controls. The levels of LPS induced IL 6 (787.82±151.97 pg/ml) and TNF α (4165.45±1501.43 pg/ml) expression in the supernatant of the culture of PBMC and plasma level of IL 6 (50.67±4.70 pg/ml) and TNF α (299.09±43.57 pg/ml) in the patients with OSAS were significantly higher than those in the normal controls (in the supernatant of the culture of PBMC: 562.69±197.54 pg/ml and 1596.25±403.08 pg/ml respectively; in the plasma: 12.69±2.75 pg/ml and 101.88±21.27 pg/ml respectively). There were significantly positive correlation between the levels of IL 6 and TNF α and the percentage of time of apnea and hyponea, as well as the percentage of time spending at SaO 2 below 90 % in the total sleep time. It was concluded that LPS induced IL 6 and TNF α levels as well as plasma IL 6 and TNF α levels in the patients with OSAS were up regulated, which may be associated with the pathogenesis of OSAS.

Tumor necrosis factor-α and interleukin-6 in cirrhotic patients with spontaneous bacterial peritonitis

AIM: To evaluate the role of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in cirrhotic patients who have hepatic and renal impairment with spontaneous bacterial peritonitis (SBP).

Claudin 1 mediates tumor necrosis factor alpha-induced cell migration in human gastric cancer cells

AIM: To investigate the role of claudin 1 in the regulation of genes involved in cell migration and tumor necrosis factor alpha (TNF-&#x003b1;)-induced gene expression in human gastric adenocarcinoma cells.

Anti Cervix Cancer Activity of Co-immobilized Tumor Necrosis Factor-α and Interferon-γ

Tumor necrosis factor α （TNF-α） and interferon-γ （IFN-γ） are cytokines with strong antitumor activities. They were reacted with a photoactive arylazide-4-azidobenzoic acid, resulting in photoactive TNF-α and IFN-γ. The infrared （IR） spectra of these products showed the characteristic absorption of an azido group at 2127 cm^-1. By photo-immobilization, this modified TNF-α and IFN-γ were immobilized on polystyrene membranes for cell culture to prepare biomaterials. The micro-morphology of photoactive cytokines was observed with a scanning electron microscope （SEM）. The inhibitory effect on growth of Hela cells and inducing apoptosis activity of these two cytokines were analyzed by growth curve, transmission electron microscope （TEM） and fluorescence active cell sorter （FACS）. The results showed that co-immobilization of IFN-γ and TNF-α had significant inhibitory effect on growth of Hela cells, inhibitory rate up to 82%, and IFN-γ had obviously synergistic action.

Molecular mechanism of action of anti-tumor necrosis factor antibodies in inflammatory bowel diseases

Anti-tumor necrosis factor(TNF) antibodies are successfully used in the therapy of inflammatory bowel diseases(IBD). However, the molecular mechanism of action of these agents is still a matter of debate. Apart from neutralization of TNF, influence on the intestinal barrier function, induction of apoptosis in mucosal immune cells, formation of regulatory macrophages as well as other immune modulating properties have been discussed as central features. Nevertheless, clinically effective anti-TNF antibodies were shown to differ in their mode-of-action in vivo and in vitro. Furthermore, the anti-TNF agent etanercept is effective in the treatment of rheumatoid arthritis but failed to induce clinical response in Crohn's disease patients, suggesting different contributions of TNF in the pathogenesis of these inflammatory diseases. In the following, we will review different aspects regarding the mechanism of action of anti-TNF agents in general and analyze comparatively different effects of each antiTNF agent such as TNF neutralization, modulation of the immune system, reverse signaling and induction of apoptosis. We discuss the relevance of the membranebound form of TNF compared to the soluble form for the immunopathogenesis of IBD. Furthermore, we review reports that could lead to personalized medicine approaches regarding treatment with antiTNF antibodies in chronic intestinal inflammation, by predicting response to therapy.

TUMOR NECROSIS FACTOR-ALPHA POLYMORPHISM AND SECRETION IN MYASTHENIA GRAVIS

Objective To analyze the relationship between tumor necrosis factor-alpha (TNFα) gene promoter -308 polymorphism and myasthenia gravis (MG) in Chinese and analyze secretion of TNFα in peripheral blood mononuclear cells (PBMC) in MG patients. Methods A biallelic polymorphism at position -308 in the promoter of TNFα gene was screened by PCR amplification and NcoI recognition site. One hundred and twenty-three MG cases and 115 healthy controls were included in this study. MG patients were classified to different groups according to clinical type, age at onset, and sex respectively. PBMC were isolated from 20 patients and 20 healthy controls, and then cultured in the presence or absence of phytohemag- glutinin (PHA) and acetycholine receptors (AchR). The supernatants were harvested after incubation and stored until TNFα was assayed by enzyme-linked immunosorbent assay. Results The frequency of TNFα-308 allele 2 (A) was found significantly increase in MG patients and showed a trend especially in late onset (≥ 40 years) and male patients (P < 0.05). The allele A had no relationship with thymic pathogenesis in MG patients. But frequency of allele A was significantly higher in general type than in ocular type (P < 0.05). MG patients had a higher inducible level of TNFα by PHA and AchR, and could be down regulated after treatment. Conclusion Polymorphism in TNFα gene promoter -308 is associated with onset of MG. The microsatellite allele TNFα2 confer risk for the development of MG in Chinese patients. MG patients have a higher inducible level of TNFα.