[Phenotype and genotype characteristics of children with cardiomyopathy associated with MYH7 gene mutation: a retrospective analysis]. / MYH7åŸºå› å˜å¼‚ç›¸å ³å„¿ç«¥å¿ƒè‚Œç— è¡¨åž‹ä¸ŽåŸºå› åž‹ç‰¹ç‚¹çš„å›žé¡¾æ€§åˆ†æž.

OBJECTIVES: To investigate the clinical phenotype and genotype characteristics of children withcardiomyopathy (CM) associated with MYH7 gene mutation. METHODS: A retrospective analysis was conducted on the medical data of five children with CM caused by MYH7 gene mutation who were diagnosed and treated in the Department of Cardiology, Hebei Children's Hospital. RESULTS: Among the five children with CM, there were three girls and two boys, all of whom carried MYH7 gene mutation. Seven mutation sites were identified, among which five were not reported before. Among the five children, there were three children with hypertrophic cardiomyopathy, one child with dilated cardiomyopathy, and one child with noncompaction cardiomyopathy. The age ranged from 6 to 156 months at the initial diagnosis. At the initial diagnosis, two children had the manifestations of heart failure such as cough, shortness of breath, poor feeding, and cyanosis of lips, as well as delayed development; one child had palpitation, blackness, and syncope; one child had fever, runny nose, and abnormal liver function; all five children had a reduction in activity endurance. All five children received pharmacotherapy for improving cardiac function and survived after follow-up for 7-24 months. CONCLUSIONS: The age of onset varies in children with CM caused by MYH7 gene mutation, and most children lack specific clinical manifestations at the initial diagnosis and may have the phenotype of hypertrophic cardiomyopathy, dilated cardiomyopathy or noncompaction cardiomyopathy. The children receiving early genetic diagnosis and pharmacological intervention result in a favorable short-term prognosis.

[Clinical and genetic characteristics of children with primary dilated cardiomyopathy]. / å„¿ç«¥åŽŸå‘æ€§æ‰©å¼ åž‹å¿ƒè‚Œç— çš„ä¸´åºŠç‰¹å¾åŠé—ä¼ å­¦åˆ†æž.

OBJECTIVES: To study the genetic characteristics, clinical characteristics, and prognosis of children with primary dilated cardiomyopathy (DCM). METHODS: A retrospective analysis was performed on the medical data of 44 children who were diagnosed with DCM in Hebei Children's Hospital from July 2018 to February 2023. According to the genetic testing results, they were divided into two groups: gene mutation-positive group (n=17) and gene mutation-negative group (n=27). The two groups were compared in terms of clinical data at initial diagnosis and follow-up data. RESULTS: Among the 44 children with DCM, there were 21 boys (48%) and 23 girls (52%). Respiratory symptoms including cough and shortness of breath were the most common symptom at initial diagnosis (34%, 15/44). The detection rate of gene mutations was 39% (17/44). There were no significant differences between the two groups in clinical characteristics, proportion of children with cardiac function grade Ⅲ or Ⅳ, brain natriuretic peptide levels, left ventricular ejection fraction, and left ventricular fractional shortening at initial diagnosis (P>0.05). The median follow-up time was 23 months, and 9 children (20%) died, including 8 children from the gene mutation-positive group, among whom 3 had TTN gene mutation, 2 had LMNA gene mutation, 2 had TAZ gene mutation, and 1 had ATAD3A gene mutation. The gene mutation-positive group had a significantly higher mortality rate than the gene mutation-negative group (P<0.05). CONCLUSIONS: There is no correlation between the severity of DCM at initial diagnosis and gene mutations in children. However, children with gene mutations may have a poorer prognosis.

[Recent research on childhood hypertrophic cardiomyopathy caused by MYH7 gene mutations]. / MYH7åŸºå› çªå˜è‡´å„¿ç«¥è‚¥åŽšåž‹å¿ƒè‚Œç— çš„ç ”ç©¶è¿›å±•.

Hypertrophic cardiomyopathy (HCM) is the most common monogenic inherited myocardial disease in children, and mutations in sarcomere genes (such as MYH7 and MYBPC3) are the most common genetic etiology of HCM, among which mutations in the MYH7 gene are the most common and account for 30%-50%. MYH7 gene mutations have the characteristics of being affected by environmental factors, coexisting with multiple genetic variations, and age-dependent penetrance, which leads to different or overlapping clinical phenotypes in children, including various cardiomyopathies and skeletal myopathies. At present, the pathogenesis, course, and prognosis of HCM caused by MYH7 gene mutations in children remain unclear. This article summarizes the possible pathogenesis, clinical phenotype, and treatment of HCM caused by MYH7 gene mutations, in order to facilitate the accurate prognostic evaluation and individualized management and treatment of the children with this disorder.

An EGFR L858R mutation identified in 1862 Chinese NSCLC patients can be a promising neoantigen vaccine therapeutic strategy.

Background: This study aimed to develop a vaccine that targets mutation-derived neoantigen in Chinese non-small-cell lung cancer (NSCLC). Methods: A cohort of 1862 Chinese NSCLC patients who underwent targeted sequencing with a 1021-gene panel was investigated. HLA typing was done using OptiType v1.0 and neoantigens were predicted by netMHCpan v4.0. HLA LOH was inferred using the lohhla algorithm and TMB were quantified by counting the total number of non-synonymous ones based on our panel data. CIBERSORT was utilized to estimate the TME in different EGFR mutant subtype by using TCGA data. Results: HLA-A*11:01(42.59%) was the top one allele and HLA-A*33:03(12.94%) ranked 12th. EGFR L858R (22.61%) was the most prevalent gene variant. The binding affinity (IC50 MT = 22.9 nM) and shared frequency (2.93%) of EGFR L858R in combination with HLA-A*33:03 were optimal. In a subsequent further analysis on immunological features of EGFR mutant subtypes, 63.1% HLA loss of heterozygosity LOH (HLA LOH) and 0.37% (7 of 1862) B2M aberrations were found in our population, both had no significant association with EGFR mutant subtypes suggesting that the process of antigen presentation involved HLA LOH and B2M mechanisms in EGFR L858R is working. Tumor mutation burden (TMB) was investigated by utilizing our panel and showed that EGFR L858R had the lowest TMB compared with other EGFR mutant subtypes. In addition, analysis of 22 immune cell types from The Cancer Genome Atlas (TCGA) data showed EGFR L858R was correlated with low level of CD8 T cells, activated CD4 memory T cells and elevated level of macrophage M2 suggesting an inhibited tumor microenvironment (TME). Conclusion: Our study identified that EGFR L858R neoantigen had the potential to generate cancer vaccines in NSCLC patients with HLA A*33:03. The neoantigen-based vaccines may become an effective salvage regimen for EGFR L858R subgroup after targeted therapy or immune checkpoint inhibitors (ICIs) failure.

A Pilot Study on the Repetitive Transcranial Magnetic Stimulation of Aß and Tau Levels in Rhesus Monkey Cerebrospinal Fluid.

Previous studies have demonstrated that a non-invasive light-flickering regime and auditory tone stimulation could affect Aß and tau metabolism in the brain. As a non-invasive technique, repetitive transcranial magnetic stimulation (rTMS) has been applied for the treatment of neurodegenerative disorders. This study explored the effects of rTMS on Aß and tau levels in rhesus monkey cerebrospinal fluid (CSF). This is a single-blind, self-controlled study. Three different frequencies (low frequency, 1 Hz; high frequencies, 20 Hz and 40 Hz) of rTMS were used to stimulate the bilateral-dorsolateral prefrontal cortex (DLPFC) of the rhesus monkey. A catheterization method was used to collect CSF. All samples were subjected to liquid chip detection to analyze CSF biomarkers (Aß42, Aß42/Aß40, tTau, pTau). CSF biomarker levels changed with time after stimulation by rTMS. After stimulation, the Aß42 level in CSF showed an upward trend at all frequencies (1 Hz, 20 Hz, and 40 Hz), with more significant differences for the high-frequencies (p < 0.05) than for the low frequency. After high-frequency rTMS, the total Tau (tTau) level of CSF immediately increased at the post-rTMS timepoint (p < 0.05) and gradually decreased by 24 h. Moreover, the results showed that the level of phosphorylated Tau (pTau) increased immediately after 40 Hz rTMS (p < 0.05). The ratio of Aß42/Aß40 showed an upward trend at 1 Hz and 20 Hz (p < 0.05). There was no significant difference in the tau levels with low-frequency (1 Hz) stimulation. Thus, high-frequencies (20 Hz and 40 Hz) of rTMS may have positive effects on Aß and tau levels in rhesus monkey CSF, while low-frequency (1 Hz) rTMS can only affect Aß levels.

Association between non-culprit healed plaque and plaque progression in acute coronary syndrome patients: an optical coherence tomography study.

BACKGROUND: Healed plaques are frequently found in patients with acute coronary syndrome, but the prognostic value is debatable. This study investigated the clinical features of non-culprit healed plaques detected by optical coherence tomography (OCT) with the aim of predicting plaque progression of healed plaques. METHODS: This study retrospectively analyzed 113 non-culprit lesions from 85 patients who underwent baseline OCT imaging and follow-up angiography from January 2015 to December 2019. Plaque progression predictors were assessed by multivariate analysis. RESULTS: Among 113 non-culprit lesions, 27 healed plaques (23.9%) were identified. Patients with non-culprit healed plaques had prior antiplatelet therapy (65.0% vs. 33.8%, P = 0.019), hypertension (85.0% vs. 50.7%, P = 0.009), and dyslipidemia (70.0% vs. 41.5%, P = 0.04) which were more frequently than those without healed plaques. The thickness (r = 0.674, P < 0.001), arc ( r = 0.736, P < 0.001), and volume ( r = 0.541, P = 0.004) of healed plaque were correlated with minimum lumen diameter changes. At a mean follow-up of 11.5 months, the non-culprit healed plaques had a lower minimum lumen diameter (1.61 ± 0.46 mm vs. 1.91 ± 0.73 mm, P = 0.016), lower average lumen diameter (1.86 mm vs. 2.10 mm, P = 0.033), and a higher degree of diameter stenosis (41.4% ± 11.9% vs. 35.5% ± 13.1%, P = 0.031) when compared to baseline measurements. The plaque progression rate was higher in the healed plaque group (33.3% vs. 8.1%, P = 0.002), and multivariate analysis identified healed plaques [odds ratio (OR) = 8.49, 95% CI: 1.71-42.13] and lumen thrombus (OR = 10.69, 95% CI: 2.21-51.71) as predictors of subsequent lesion progression. CONCLUSIONS: Healed plaques were a predictor for rapid plaque progression. The quantitative parameters of healed plaque showed a good agreement with plaque progression. Patients with healed plaque were associated with prior antiplatelet therapy and high level of low-density lipoprotein cholesterol. Bifurcation lesions might be the predilection sites of healed plaques.

A new image encryption algorithm based on the OF-LSTMS and chaotic sequences.

In this paper, a novel image encryption algorithm based on the Once Forward Long Short Term Memory Structure (OF-LSTMS) and the Two-Dimensional Coupled Map Lattice (2DCML) fractional-order chaotic system is proposed. The original image is divided into several image blocks, each of which is input into the OF-LSTMS as a pixel sub-sequence. According to the chaotic sequences generated by the 2DCML fractional-order chaotic system, the parameters of the input gate, output gate and memory unit of the OF-LSTMS are initialized, and the pixel positions are changed at the same time of changing the pixel values, achieving the synchronization of permutation and diffusion operations, which greatly improves the efficiency of image encryption and reduces the time consumption. In addition the 2DCML fractional-order chaotic system has better chaotic ergodicity and the values of chaotic sequences are larger than the traditional chaotic system. Therefore, it is very suitable to image encryption. Many simulation results show that the proposed scheme has higher security and efficiency comparing with previous schemes.

Sitagliptin attenuates the progression of coronary atherosclerosis in patients with coronary disease and type 2 diabetes.

BACKGROUND AND AIMS: Type 2 diabetes mellitus (T2DM) is a well-recognized independent risk factor for ASCVD, the aim of this study was to investigate the effects of a dipeptidyl peptidase-4 inhibitor, sitagliptin, on prevention of progression of coronary atherosclerosis assessed by three-dimensional quantitative coronary angiography (3D-QCA) in T2DM patients with coronary artery disease (CAD). METHODS: This was a prospective, randomized, double-center, open-label, blinded end point, controlled 18-month study in patients with CAD and T2DM. A total of 149 patients, who had at least 1 atherosclerotic plaque with 20%-80% luminal narrowing in a coronary artery, and had not undergone intervention during a clinically indicated coronary angiography or percutaneous coronary intervention, were randomized to sitagliptin group (n = 74) or control group (n = 75). Atherosclerosis progression was measured by repeat 3D-QCA examination in 88 patients at study completion. The primary outcome was changes in percent atheroma volume (PAV) from baseline to study completion measured by 3D-QCA. Secondary outcomes included change in 3D-QCA-derived total atheroma volume (TAV) and late lumen loss (LLL). RESULTS: The primary outcome of PAV increased of 1.69% (95%CL, -0.8%-4.2%) with sitagliptin and 5.12% (95%CL, 3.49%-6.74%) with the conventional treatment (p = 0.023). The secondary outcome of change in TAV in patients treated with sitagliptin increased of 6.45 mm3 (95%CL,-2.46 to 6.36 mm3) and 9.45 mm3 (95%CL,-4.52 to 10.14 mm3) with conventional treatment (p = 0.023), however, no significant difference between groups was observed (p = 0.175). Patients treated with sitagliptin had similar LLL as compared with conventional antidiabetics (-0.06, 95%CL, -0.22 to 0.03 vs. -0.08, -0.23 to -0.03 mm, p = 0.689). CONCLUSIONS: In patients with type 2 diabetes and coronary artery disease, treatment with sitagliptin resulted in a significantly lower rate of progression of coronary atherosclerosis compared with conventional treatment.

Assessment of the Cerebral Hemodynamic Benefits of Carotid Artery Stenting for Patients with Preoperative Hemodynamic Impairment Using Cerebral Single Photon Emission Computed Tomography (SPECT) and Carbon Dioxide Inhalation.

BACKGROUND The aim of this study was to evaluate the effects of carotid artery angioplasty and carotid artery stenting (CAS) on cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) in patients with preoperative cerebrovascular hemodynamic impairment. MATERIAL AND METHODS Seventeen patients with unilateral severe internal carotid artery (ICA) stenosis and ipsilateral CVR impairment underwent CAS. CBF and CVR were measured by single photon emission computed tomography (SPECT) with inhalation of carbon dioxide (CO2) one week before and three months after CAS. Sixty-eight ROIs in the middle cerebral artery (MCA) territory were analyzed in 17 patients. RESULTS Before CAS, CVR was impaired in all ROIs. CBF was impaired in 16 ROIs (23.5%). The percentage of ROIs with impaired CBF was significantly increased in patients with ≥90% carotid artery stenosis (p=0.047) without collateral flow through the circle of Willis (p=0.005). CAS significantly increased CVR in ROIs with a normal preoperative CBF and impaired CVR, indicating mild hemodynamic impairment (0.9±6.7% vs. 4.9±8.6%) (p=0.014). CAS significantly increased CBF in ROIs with preoperative impaired CBF and impaired CVR, indicating severe hemodynamic impairment (79.1±7.5% vs. 86.7±10.0%) (p<0.001). Following CAS, ROIs with normal CBF and impaired CVR had a significantly increased percentage of improved CVR (p=0.047); ROIs with impaired CBF and impaired CVR had a significantly increased percentage of improved CBF (p=0.027). CONCLUSIONS The severity of preoperative hemodynamic impairment, which is related to the degree of carotid artery stenosis and cerebral collateral flow, may influence hemodynamic benefits by CAS.

Plasma dipeptidyl-peptidase-4 activity is associated with left ventricular systolic function in patients with ST-segment elevation myocardial infarction.

Plasma dipeptidyl-peptidase-4 activity (DPP4a) is inversely associated with left ventricular function in patients with heart failure (HF) or diabetes. However, the association between DPP4a and left ventricular function in ST-segment elevation myocardial infarction (STEMI) patients has not been reported. We studied this association in 584 consecutive STEMI patients at a tertiary referral center from July 2014 to October 2015. DPP4a and plasma N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) levels were quantified by enzymatic assays. The median serum NT-proBNP levels were highest in patients of the lowest tertile (T1) of DPP4a compared with that of the highest tertile (T3) (p = 0.028). The STEMI patients in T1 exhibited lower left ventricular systolic function (T1 vs. T3: left ventricular ejection fraction (LVEF): 50.13 ± 9.12 vs. 52.85 ± 6.82%, p = 0.001). Multivariate logistic-regression analyses (adjusted for confounding variables) showed that a 1 U/L increase in DPP4a was associated with a decreased incidence of left ventricular systolic dysfunction (LVSD) (adjusted odds ratio: 0.90; 95% CI: 0.87-0.94; p < 0.01). In conclusion, low DPP4a is independently associated with LVSD in STEMI patients, which suggests that DPP4 may be involved in the mechanisms of LVSD in STEMI patients.

Delayed reendothelialization with rapamycin is rescued by the addition of nicorandil in balloon-injured rat carotid arteries.

Rapamycin is an immunosuppressive agent that is added to drug eluting stents. It prevents restenosis, but it also impairs reendothelialization. Nicorandil is a hybrid agent with adenosine triphosphated (ATP)-sensitive K+ (KATP) channel opener and nitrate properties. It prevents oxidative stress and cell apoptosis induced by rapamycin in endothelial cells in vitro. However, whether nicorandil promotes reendothelialization after angioplasty delayed by rapamycin remains to be determined. Balloon injury model was established in SD rats. Nicorandil increased reendothelialization impaired by rapamycin, and it decreased xanthine oxidase (XO)-generated reactive oxygen species (ROS) induced by rapamycin. In addition, eNOS expression inhibited by rapamycin was increased by nicorandil in vivo. In vitro, rapamycin-impeded cardiac microvascular endothelial cells (CMECs) migration, proliferation and rapamycin-induced ROS production were reversed by nicorandil. Knockdown of XO partially inhibited rapamycin-induced ROS production and cell apoptosis in CMECs, and it promoted CMECs migration and proliferation suppressed by rapamycin. Knockdown of Akt partially prevents eNOS upregulation promoted by nicorandil. The beneficial effect of nicorandil is exhibited by inhibiting XO and up-regulating Akt pathway. Nicorandil combined with rapamycin in effect rescue the deficiencies of rapamycin alone in arterial healing after angioplasty.

Hepatocyte growth factor inhibits hypoxia/reoxygenation-induced activation of xanthine oxidase in endothelial cells through the JAK2 signaling pathway.

Vascular endothelial cells (ECs) appear to be one of the primary targets of hypoxia/reoxygenation (H/R) injury. In our previous study, we demonstrated that hepatocyte growth factor (HGF) exhibited a protective effect in cardiac microvascular endothelial cells (CMECs) subjected to H/R by inhibiting xanthine oxidase (XO) by reducing the cytosolic Ca2+ concentration increased in response to H/R. The precise mechanisms through which HGF inhibits XO activation remain to be determined. In the present study, we examined the signaling pathway through which HGF regulates Ca2+ concentrations and the activation of XO during H/R in primary cultured rat CMECs. CMECs were exposed to 4 h of hypoxia and 1 h of reoxygenation. The protein expression of XO and the activation of the phosphoinositide 3-kinase (PI3K), janus kinase 2 (JAK2) and p38 mitogen-activated protein kinase (p38 MAPK) signaling pathways were detected by western blot analysis. Cytosolic calcium (Ca2+) concentrations and reactive oxygen species (ROS) levels were measured by flow cytometry. The small interfering RNA (siRNA)­mediated knockdown of XO inhibited the increase in ROS production induced by H/R. LY294002 and AG490 inhibited the H/R-induced increase in the production and activation of XO. The PI3K and JAK2 signaling pathways were activated by H/R. The siRNA­mediated knockdown of PI3K and JAK2 also inhibited the increase in the production of XO protein. HGF inhibited JAK2 activation whereas it had no effect on PI3K activation. The siRNA-mediated knockdown of JAK2 prevented the increase in cytosolic Ca2+ induced by H/R. Taken together, these findings suggest that H/R induces the production and activation of XO through the JAK2 and PI3K signaling pathways. Furthermore, HGF prevents XO activation following H/R primarily by inhibiting the JAK2 signaling pathway and in turn, inhibiting the increase in cytosolic Ca2+.

Nicorandil attenuates carotid intimal hyperplasia after balloon catheter injury in diabetic rats.

BACKGROUND: Diabetic patients suffer from undesired intimal hyperplasia after angioplasty. Nicorandil has a trend to reduce the rate of target lesion revascularization. However, whether nicorandil inhibits intimal hyperplasia and the possible mechanisms underlying it remain to be determined. We aimed at assessing the effect of nicorandil on intimal hyperplasia in diabetic rats. METHODS: After intraperitoneal injection of streptozotocin (STZ, 50 mg/kg), balloon injury model was established in carotid arteries of diabetic rats. Rats were randomized to vehicle, nicorandil (15 mg/kg/day) or 5-hydroxydecanoate (5-HD, 10 mg/kg/day), a mitochondrial ATP-sensitive potassium channel (mitoKATP channel)-selective antagonist. Perivascular delivery of εPKC siRNA was conducted to determine the role of εPKC pathway in intimal hyperplasia. In hyperglycemia environment (25 mM glucose), primary culture of vascular smooth muscle cells (VSMCs) were treated with nicorandil or 5-HD. Cell proliferation and cell migration were analyzed. RESULTS: Intimal hyperplasia significantly increased 14 days after balloon injury in diabetic rats (p < 0.01). Nicorandil inhibited intima development, reduced inflammation and prevented cell proliferation in balloon-injured arteries (p < 0.01). The protective effects of nicorandil were reversed by 5-HD (p < 0.05). εPKC was activated in balloon-injured arteries (p < 0.01). Nicorandil inhibited εPKC activation by opening mitoKATP channel. Perivascular delivery of εPKC siRNA inhibited intimal hyperplasia, inflammation and cell proliferation (p < 0.01). High glucose-induced VSMCs proliferation and migration were inhibited by nicorandil. εPKC activation induced by high glucose was also inhibited by nicorandil and that is partially reversed by 5-HD. εPKC knockdown prevented VSMCs proliferation and migration (p < 0.01). CONCLUSIONS: Our study demonstrates that nicorandil inhibits intimal hyperplasia in balloon-injured arteries in diabetic rats. Nicorandil also prevents VSMCs proliferation and migration induced by high glucose. The beneficial effect of nicorandil is conducted via opening mitoKATP channel and inhibiting εPKC activation.

[Neutralization of interleukin-17 aggravates respiratory infection induced by Chlamydia trachomatis in mice].

OBJECTIVE: To evaluate the role of interleukin-17 (IL-17) in respiratory infection with Chlamydia trachomatis in mice. METHODS: (1) In the study, 32 mice were randomly divided into the following 4 groups (8 mice/group): neutralizing antibody group (NG), isotype-matched control antibody group (IG), compensating recombinant mouse IL-17 group (CG) and PBS control group (PG), respectively. The mice in all the groups were induced by intranasal inoculation with high dose of inclusion-forming unit (IFU) Chlamydia trachomatis mouse pneumonitis (MoPn). Meanwhile, they were injected intraperitoneally with neutralizing rat antimouse IL-17 mAb, or control rat IgG, or neutralizing rat antimouse IL-17 mAb plus recombinant mouse IL-17 or PBS alone every 48 h starting on day 1 before chlamydial infecton. The mice were monitored daily for body weight change and survival rates. (2) Another 32 mice were randomly divided into 4 groups as method (1),and intranasally infected with moderate dose of MoPn, and the following steps were taken as the same as method (1). The bronchial alveolar lavage fluids (BALF) were collected for counting neutrophils, macrophages, and lymphocytes on day 8 postinfection. At the same time, the chlamydial growth in the lung, kidney and spleen were assessed by inoculating HeLa cell monolayer with homogenates followed by immunofluoresent assay (IFA). RESULTS: After being infected by high dose of MoPn and neutralized with anti-IL-17 mAb, the average body weight change decreased obviously in all the groups and began to increase 12 d after infection in IG, CG and PG, but only the mice in NG continued to lose their body weight till all died. The survival rate of the mice decreased significantly in NG and all died on day 21 postinfection. There were significant differences compared with IG, CG and PG groups (χ(2)= 11.096,10.575,13.781, respectively, P<0.05). But the survival rates of the mice were 75%, 75% and 87.5% for IG, CG and PG respectively, and there were no significant differences among the three groups. After being infected by moderate dose of MoPn, the chlymadia growth in the lung and the spread to the kidney and spleen significantly increased in NG (6.85±0.12, 1.85±0.35, and 1.59±0.35, P<0.05), compared with IG (6.03±0.25, 0.86±0.80, 0.57±0.42), CG (5.42±0.66, 0.43±0.23, 0.21±0.15) and PG (5.65±0.29, 0.68±0.39, but not detected in the spleen), these data were expressed as lg IFUs/organ. The results of BALF cell differentials were calculated as the percentage of the total cells and the final results of neutrophils, macrophages, and lymphocytes were 54.17%±5.29%, 26.92%±6.28%, 18.90%±5.01% for NG, 74.50%±7.33%, 13.43%±5.69%, 12.06%±6.64% for IG, 76.13%±8.12%, 12.31%±7.73%, 11.56%±7.25% for CG, and 69.97%±6.45%, 14.55%±6.59%, and 15.48%±6.11% for PG. The ratios of neutrophils, macrophages, and lymphocytes in BALF of NG had significant differences compared with the other groups (P<0.001). The neutrophil population in the BALF was significantly decreased in NG than that of the other groups. CONCLUSION: After the endogenous IL-17 activity had been neutralized, the mice showed greater body weight loss, less survival rate, higher bacterial growth in the lung and more spread to other organs, and less neutrophils inflitration. These data suggest that IL-17 plays a critical protective role in the host defense against chlamydial infection.

[Preparation and identification of monoclonal antibodies against Chlamydia trachomatis Tarp protein].

OBJECTIVE: To obtain monoclonal antibodies (mAbs) against Chlamydia trachomatis Tarp protein. METHODS: Chlamydia trachomatis serovar D recombinant Tarp fusion protein was cloned and expressed. Balb/c mice were immunized with recombinant Tarp fusion protein, and the spleen cells of the immunized mice were fused with SP2/0 mouse myeloma cells. The hybridoma cell lines secreting mAbs against Tarp protein were screened by an indirect immunofluorescence assay and subcloned by limiting dilution culture. The specificities of these mAbs to Tarp were determined by ELISA, and their isotype and chlamydial species specificity identified by an indirect immunofluorescence assay. RESULTS: Recombinant GST-Tarp fusion protein with a relative molecular mass of about 136 000 was successfully cloned and expressed. Seven hybridoma cell lines stably secreting specific mAbs against Tarp protein were obtained. All the 7 mAbs reacted strongly with Tarp protein but not with other chlamydial proteins. Two mAbs were identified to belong to IgG2a isotype and the other 5 to IgG1 isotype. All the 7 mAbs reacted strongly with chlamydia serovar A, D, and L2, but not with MoPn, 6BC, or AR39. CONCLUSION: The highly specific mAbs against Tarp protein have been obtained to facilitate further study of the structure and function of Chlamydia Tarp protein.

[Cloning and expression of Chlamydia trachomatis OmcBc gene and antigenicity analysis of the protein].

OBJECTIVE: To investigate the antigenicity of recombinant Chlamydia trachomatis (Ct) OmcBc protein and search for the new target for early diagnosis of Chlamydia infection and Chlamydia vaccine development. METHODS: The C fragment of OmcB encoding the amino acids from T270 to T553 was amplified from Chlamydia serovar D genomic DNA. The pGEX-6p-Ct OmcBc expression plasmid was constructed and transformed into E.coli XL-1blue. The expression of recombinant Ct OmcBc protein was induced by IPTG. Serum samples were collected from 120 patients with urogenital Chlamydia infection. The antiserum samples were collected from 7 New Zealand white rabbits and 5 Balb/C mice immunized subcutaneously and intraperitoneally with Ct serovar D inactivated EB, respectively, and from 9 Balb/C mice intranasally infected with Ct serovar D live EB. The anti-Chlamydia specific antibody were titrated by an immunofluorescence assay (IFA). The reactivity of the recombinant OmcBc protein with all the above antisera was detected by ELISA. RESULTS: The pGEX-6p-Ct OmcBc expression plasmid was successfully constructed. DNA sequencing showed that the inserted OmcBc was about 852 bp, encoding a protein with 284 amino acids. The expression of the recombinant GST-OmcBc was induced by IPTG, producing a fusion protein with a molecular weight of about 57 kD. The titer of the specific antibodies to Chlamydia in all the antisera was high. ELISA results showed strong reactivities of the recombinant GST-OmcBc fusion protein with all the above antisera. CONCLUSIONS: OmcBc protein is an immunodominant protein of Chlamydia. The recombinant GST-OmcBc with strong antigenicity may provide a basis for further study of early diagnosis of chlamydia infection and development of Chlamydia vaccine.