[Investigation on seroprevalence of Toxoplasma gondii infections among neonates in Fujian Province]

OBJECTIVE

To investigate the seroprevalence of Toxoplasma gondii infections among neonates in Fujian Province, so as to provide insights into the development of interventions for the prevention and control of congenital toxoplasmosis.

METHODS

A total of 1 045 neonates delivered in Fujian Province from 2017 to 2018 were recruited, including 387 preterm infants and 658 full-term infants. Umbilical cord blood was sampled from all neonates, and the seroprevalence of anti-T. gondii IgG antibody was detected and compared between preterm and full-term infants. In addition, elbow venous blood samples were collected from neonates'mothers, and the seroprevalence of anti-T. gondii IgG antibody was detected and compared between preterm and full-term infants'mothers.

RESULTS

The overall seroprevalence of anti-T. gondii IgG antibody was 9.38% among the 1 045 neonates in Fujian Province. The seroprevalence of anti-T. gondii IgG antibody was 18.35% in the 387 preterm infants, and there was no significant difference in the seroprevalence of anti-T. gondii IgG antibody between male and female infants (17.69% vs. 18.75%, χ² = 0.07, P > 0.05). The seroprevalence of anti-T. gondii IgG antibody was 4.10% in the 658 full-term infants, and there was no significant difference in the seroprevalence of anti-T. gondii IgG antibody between male and female infants (4.14% vs. 4.08%, χ² = 0, P > 0.05). In addition, the overall seroprevalence of anti-T. gondii IgG antibody was 15.02% in all neonates' mothers, and the seroprevalence was significantly greater in preterm infants'mothers than in full-term infant's mothers (20.93% vs. 11.55%, χ² = 16.79, P < 0.01).

CONCLUSIONS

The seroprevalence of T. gondii infections is significantly higher in preterm infants and their mothers than in full-term infants and their mothers. Prenatal detection of T. gondii infections and health education pertaining to toxoplasmosis prevention and control knowledge are required to be strengthened to effectively reduce the incidence of congenital toxoplasmosis.

Effects of supplementing geese with green sweet sorghum stalks on microbiota in segments of the gastrointestinal tract

To explore the effects of supplementing a basal diet with green sweet sorghum stalks on the gut microbiota in geese, one hundred and twenty 28 day old geese were divided into two groups. Group 1 was fed a basal diet and group 2 was fed 92% of the same basal diet with green sweet sorghum stalks ad libitum for 42 days. Three male geese from each group were killed at 70 days old, four gastrointestinal tract segments (duodenum, jejunum, ileum, and caecum) were collected, and the hypervariable V4 region of the bacterial 16S rRNA gene was sequenced. There were obvious changes of microbiome in the caecum compared with the other three intestinal segments after green sweet sorghum stalks were added to the diet. Group 2 had significantly higher alpha diversity in the caecum compared with group 1 (P <0.05). The phyla of bacterial communities in the caecum differed. Group 2 had more abundant Bacteroidetes and Firmicutes, but Proteobacteria were more abundant in group 1. At genus level, Bacteroides was more prevalent in group 2, as were Prevotella and YRC22 (P <0.05). Functional analysis revealed that the carbohydrate metabolism, membrane transport, endocrine system and digestive system metabolic pathways were overrepresented in group 2. In conclusion, caecal microbes might play an important role in digesting green sweet sorghum stalks in geese.Keywords: caecum, goose, microbiome, microbial diversity

Immune cell infiltration features and related marker genes in lung cancer based on single-cell RNA-seq

PURPOSE

Immune cells in the immune microenvironment of lung cancer have a great impact on the development of lung cancer. Our purpose was to analyze the immune cell infiltration features and related marker genes for lung cancer.

METHODS

Single cell RNA sequencing data of 11,485 lung cancer cells were retrieved from the Gene Expression Omnibus. After quality control and data normalization, cell clustering was performed using the Seurat package. Based on the marker genes of each cell type from the CellMarker database, each cell was divided into G1, G2M, and S phases. Then, differential expression and functional enrichment analyses were performed. CIBERSORT was used to reconstruct immune cell types.

RESULTS

Following cell filtering, highly variable genes were identified for all cells. 14 cell types were clustered. Among them, CD4 + T cell, B cell, plasma cell, natural killer cell and cancer stem cell were the top five cell types. Up-regulated genes were mainly enriched in immune-related biological processes and pathways. Using CIBERSORT, we identified the significantly higher fractions of naïve B cell, memory CD4 + T cell, T follicular helper cell, T regulatory helper cell and M1 macrophage in lung cancer tissues compared to normal tissues. Furthermore, the fractions of resting NK cell, monocyte, M0 macrophage, resting mast cell, eosinophil and neutrophil were significantly lower in tumor tissues than normal tissues.

CONCLUSION

Our findings dissected the immune cell infiltration features and related marker genes for lung cancer, which might provide novel insights for the immunotherapy of lung cancer.

AB0631 THE CLINICAL CHARACTERISTICS OF SYSTEMIC SCLEROSIS WITH LUNG CANCER: DATA FROM SINGLE CENTER IN CHINA

Background:

Malignant neoplasms is the second most common non-SSc associated cause of death in SSc patients, only second to infection. And among all the neoplasms, lung cancers are the most common, which is in the urgent need of attention from clinicians.

Objectives:

To analyze the clinical features of patients of SSc with lung cancer.

Methods:

Medical records of inpatients admitted in Peking Union Medical College Hospital from March 1992 to December 2018, were collected and analyzed, including the clinical manifestation, laboratory data, radiological images, pathology. SSc patients without lung cancer during the same period, matched by age and gender, were selected as the controls.

Results:

Nineteen SSc patients with complete medical records were identified, with 17 (89.5%) females and 2 (10.5%) males. The mean age of SSc onset was 37.8±12.0) years old and of lung cancer diagnosis was (54.4±10.2) years old. One (5.3%) had a smoking history. Eight (42.1%) patients had family history of cancer, which was significantly higher than those without lung cancer (4 patients, 5.3%, P<0.001). The proportion of limited cutaneous SSc (lcSSc) were 63.2% among these patients, and 18 (94.7%) had interstitial lung disease (ILD), the difference between the two groups was not statistically significant (P = 0.259 and 0.051, respectively). All ILD was diagnosed before the onset of lung cancer, with a median interval of 9.2 (range 1.6-28.1) years. SSc patients with lung cancer had less myositis than control group (0% vs. 27.6%, P = 0.032), yet no significant differences were identified in Raynaud’s syndrome, esophageal involvement, digital ulcers, pulmonary hypertension, telangiectasia and arthritis. All patients developed lung cancer after the diagnosis of SSc, with a median interval 10.5 (range 2.0-36.2) years. In most of them(18, 94.7%), lung cancer happened after at least 6 years of SSc onset. Newly happened cough (9 patients), worsening decrease in activity endurance (3), chest pain (2), hemoptysis (2), nodes in lung through regular CT scans (3) were the first presentations of lung cancer. Ten(62.5%) neoplasms developed in the lower lobes of the lung, while 3 was in the upper lobes, one in the lingual lobe, and one in the left pulmonary hilum, and 3 were unknown. The median survival of the case group were 31.4 years, while the median survival of the control group was not reached. Eight patients tested EGFR gene mutation or ALK gene rearrangement, and only 2 were positive.

Conclusion:

It is not uncommon that SSc could be concomitant with lung cancer, especially for those with long disease duration and family history of malignancy. Due to the subtle onset of lung cancer, clinicians should pay attention to it during clinical practice.

References:

[1]Hu S et al. Arthritis Res Ther, 2018, 20:235.

[2]Steen VD, Ann Rheum Dis, 2007, 66:940-944.

[3]Tyndall AJ et al. Ann Rheum Dis, 2010, 69:1809-1815.

[4]Compton CC et al. AJCC Cancer Staging Atlas [M]. 7th ed. New York:Springer, 2012:311-328.

[5]Detterbeck FC et al. Chest, 2016, 1:193-203.

[6]Kuo CF et al. J Rheumatol, 2012, 41:44-49.

[7]Nishioka K et al. J Dermatol, 1996, 23:677-682.

[8]Ling Z, et al. 2016, 10:238-241.

[9]Heist RS et al. J Thorac Oncol, 2012, 7:1775-1780.

[10]Kim HR et al. J Clin Oncol, 2013, 31:731-737.

[11]Igusa T et al. Ann Rheum Dis, 2018, 77:1179-1186.

[12]Hill CL et al. Lancet, 2001, 357:96-100.

[13]Pontifex EK et al. Ann Rheum Dis, 2007, 66:551-553.

[14]Thun MJ et al. N Engl J Med, 2013, 368:351-364.

Disclosure of Interests:

Hui Zhong: None declared, Jiaxin Zhou: None declared, Shangzhu Zhang: None declared, Yan Xu: None declared, Yong Hou: None declared, Mengtao Li: None declared, Dong Xu: None declared, Mengzhao Wang: None declared, Xiaofeng Zeng Consultant of: MSD Pharmaceuticals

OP0032 ERAP1-MEDIATED IMMUNOGENICITY AND IMMUNE-PHENOTYPES IN HLA-B51+ BEHÇET’S DISEASE POINT TO PATHOGENIC CD8 T CELL EFFECTOR RESPONSES

Background:

HLA-B51 is a definite risk factor for Behçet’s disease (BD). A coding variant of ERAP1, Hap10 – with low peptide-trimming activity – vastly potentiates this risk, but is mechanistically unclear1,2).

Objectives:

To test the hypothesis that low or absent ERAP1 activity alters CD8 T cell immunogenicity through changes in the HLA-B51 peptidome and shapes the CD8 T cell immune response in affected subjects.

Methods:

We generated HLA-B51+ERAP1 KO LCL clones using CRISPR-Cas9, performed mass spectrometry of the immunoprecipitated MHC-class I peptidome with subsequent computational deconvolution for HLA-B51-binding peptides. We then assessed single cell (ICS), bulk (ELISA) and proliferative (CFSE) CD8 effector (IFNg, granzyme B, perforin) T cell responses through stimulation of allogeneic donor cells with WT vs KO LCL and determined ERAP1 haplotypes in 49 untreated Turkish BD subjects with ocular and/ or major vascular involvement as well as healthy donors (HD) whose PBMC were profiled using 6 multicolour flow cytometry panels.

Results:

WT and KO peptidomes differed significantly (p<0.0005 Fisher’s exact test) with a distinctive shift of peptide length frequencies exceeding 9-mer (binding optimum) in the KO vs WT. This held true for computationally deconvoluted HLA-B51 binders. IFNg secretion from CD8 T cells stimulated with KO LCL was significantly different from WT (ICS, p=0.0006; ELISA, p=0.0059) as were CD8 T cell proliferation and ICS of perforin/granzyme B+CD8 T cells. Analysis of 133 T, B, NK and monocyte cell populations revealed predominance of CD8 T and NKT cell subset in HLA-B51+/Hap10+ BD vs HLA-B51+/Hap10- BD and HD, accounting for 80% of all populations reaching significance (p<0.05, Mann-Whitney). Naive and effector memory CD8 T cell subsets were inversely correlated. Cohen’s effect sizes were large (>0.8) or very large (>1.2).

Conclusion:

We show that absence of functional ERAP1 alters human CD8 T cell immunogenicity. This is mediated by an HLA-class I peptidome with propensity for longer peptides above 9mer and suggests loss or de-novo presentation of peptide-HLA-B51 complexes to cognate CD8 TCR. The reciprocal changes in antigen- experienced vs naive CD8 T cell subsets in affected subjects point to biologic significance of HLA-B51/Hap10 in BD. Collectively, our findings suggest that an altered HLA-B51 peptidome modulates immunogenicity of CD8 effector T cells in ERAP1-Hap10 carriers with BD and identify targets for future drug development.

References:

[1]Kirino, Y., G. Bertsias, Y. Ishigatsubo, N. Mizuki, I. Tugal-Tutkun, E. Seyahi, Y. Ozyazgan, F. S. Sacli, B. Erer, H. Inoko, Z. Emrence, A. Cakar, N. Abaci, D. Ustek, C. Satorius, A. Ueda, M. Takeno, Y. Kim, G. M. Wood, M. J. Ombrello, A. Meguro, A. Gul, E. F. Remmers, and D. L. Kastner. 2013. ‘Genome-wide association analysis identifies new susceptibility loci for Behcet’s disease and epistasis between HLA-B*51 and ERAP1’,Nat Genet, 45: 202-7.

[2]Takeuchi, M., M. J. Ombrello, Y. Kirino, B. Erer, I. Tugal-Tutkun, E. Seyahi, Y. Ozyazgan, N. R. Watts, A. Gul, D. L. Kastner, and E. F. Remmers. 2016. ‘A single endoplasmic reticulum aminopeptidase-1 protein allotype is a strong risk factor for Behcet’s disease in HLA-B*51 carriers’,Ann Rheum Dis, 75: 2208-11.

Disclosure of Interests:

Arshed F. Al-Obeidi: None declared, Ann Cavers: None declared, Yesim Ozguler: None declared, Olivier Manches: None declared, Hua Zhong: None declared, Berna Yurttas: None declared, Beatrix Ueberheide: None declared, Gulen Hatemi Grant/research support from: BMS, Celgene Corporation, Silk Road Therapeutics – grant/research support, Consultant of: Bayer, Eli Lilly – consultant, Speakers bureau: AbbVie, Mustafa Nevzat, Novartis, UCB – speaker, Matthias Kugler: None declared, Johannes Nowatzky: None declared

Molecular cloning of the goose GnRH gene and identification of GnRH polymorphisms associated with laying traits

1. Egg-laying traits are important economic characteristics in goose production (Anser cygnoides). The gene GnRH, which encodes gonadotropin-releasing hormone, is a strong candidate gene for egg-laying traits in avian species. 2. In this study, a 3520 bp genomic sequence and a 279 bp mRNA sequence for GnRH, which encoded 92 amino acids, were determined. The GnRH DNA sequence contains four exons and three introns, and the DNA and deduced amino acid sequences were highly conserved across mammals (human, macaque, cow, and sheep) and avians (chicken, fulmar and quail). 3. Using a direct sequencing method, 46 single nucleotide polymorphisms (SNPs) were identified in the GnRH genomic sequence that were shared between two Sichuan White goose populations (217 and 208 individuals). Furthermore, 44 haplotypes were constructed using a sliding window approach. Association analysis between the SNPs and haplotypes and egg-laying traits showed that 10 SNPs affected the first egg weight, average egg weight, egg number at 48 weeks and egg number at 64 weeks. 4. These results lay the foundation for further studies of the function of GnRH in geese and provide a theoretical basis for marker-assisted selection of egg-laying traits in the Sichuan white goose population.

MicroRNA-9501 inhibits breast cancer proliferation and metastasis through regulating Wnt/β-catenin pathway

OBJECTIVE

This research was designed to explore the expression characteristics of microRNA-9501 in breast cancer (BCa), and to further explore whether it can influence the development of BCa through the regulation of Wnt/β-Catenin pathway.

PATIENTS AND METHODS

QPCR was carried out to examine microRNA-9501 level in tumor tissue samples and paracancerous ones collected from 42 BCa patients, and the interplay between microRNA-9501 expression and the clinical indicators, as well as the prognosis of BCa patients were analyzed. In addition, we detected microRNA-9501 expression in BCa cell lines by qPCR. Subsequently, microRNA-9501 overexpression model was constructed in BCa cell lines MCF-7 and MDA-MB-231. Then, CCK-8, EdU, cell wound healing, as well as transwell assays, were carried out to evaluate the impact of microRNA-9501 on the biological functions of BCa cells. Finally, the Dual-Luciferase reporting test and tumor formation experiment in nude mice were conducted to further clarify the potential molecular mechanism.

RESULTS

QPCR results indicated that microRNA-9501 level in tumor tissue specimens of BCa patients was remarkably higher than that in adjacent ones, and the difference was statistically significant. Compared with patients with high expression of microRNA-9501, patients with lowly-expressed microRNA-9501 had higher tumor stage, higher incidence of lymph node or distant metastasis, and lower overall survival rate. In addition, compared with control group, cells in microRNA-9501 overexpression group showed a significant decrease in proliferation rate, invasiveness, and migration ability. Meanwhile, luciferase reporting assay revealed that overexpression of β-Catenin remarkably attenuated the luciferase activity of the vector containing wild-type microRNA-9501 sequences, further demonstrating that microRNA-9501 can be targeted by β-Catenin. Meanwhile, qPCR revealed a negative association between β-Catenin and microRNA-9501 in BCa tissues. Finally, tumor-bearing experiments in nude mice also demonstrated that microRNA-9501 may suppress the malignant growth of breast tumor.

CONCLUSIONS

MicroRNA-9501 expression was found remarkably decreased in BCa tissues and cell lines, which was closely relevant to the pathological stage, metastasis incidence, and prognosis of BCa patients. In addition, microRNA-9501 may suppress the malignant progression of BCa via modulating Wnt/β-Catenin path-way.

Live Neuron High-Content Screening Reveals Synaptotoxic Activity in Alzheimer Mouse Model Homogenates

Accurate quantification of synaptic changes is essential for understanding the molecular mechanisms of synaptogenesis, synaptic plasticity, and synaptic toxicity. Here we demonstrate a robust high-content imaging method for the assessment of synaptic changes and apply the method to brain homogenates from an Alzheimer's disease mouse model. Our method uses serial imaging of endogenous fluorescent labeled presynaptic VAMP2 and postsynaptic PSD95 in long-term cultured live primary neurons in 96 well microplates, and uses automatic image analysis to quantify the number of colocalized mature synaptic puncta for the assessment of synaptic changes in live neurons. As a control, we demonstrated that our synaptic puncta assay is at least 10-fold more sensitive to the toxic effects of glutamate than the MTT assay. Using our assay, we have compared synaptotoxic activities in size-exclusion chromatography fractioned protein samples from 3xTg-AD mouse model brain homogenates. Multiple synaptotoxic activities were found in high and low molecular weight fractions. Amyloid-beta immunodepletion alleviated some but not all of the synaptotoxic activities. Although the biochemical entities responsible for the synaptotoxic activities have yet to be determined, these proof-of-concept results demonstrate that this novel assay may have many potential mechanistic and therapeutic applications.

The direct effects of gonadotropin-releasing hormone on proliferation of granulosa cells and development of follicles in goose

1. The study objectives were to determine the direct effects of gonadotropin-releasing hormone (GnRH) on the proliferation of ovarian granulosa cells (GCs) and the development of follicles in geese (Anser cygnoides) by colorimetry and ethynyl-2'-deoxyuridine (EdU) cell proliferation assays, in which primary GCs were treated with different concentrations of GnRH agonist (alarelin acetate) and an antagonist (cetrorelix acetate). Differently expressed genes (DEGs) were identified by RNA-sequencing and validated by quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blotting. 2. The EdU assays showed that the proliferation of GCs was affected by the GnRH agonist and antagonist in a dose-dependent manner. The effect of treatment on cell proliferation was statistically significant at the concentrations of 10^-5 mol/l alarelin and 1 mg/l cetrorelix acetate. A total of 134 DEGs (76 downregulated and 58 upregulated for alarelin treatment) and 226 DEGs (90 downregulated and 136 upregulated for cetrorelix) were identified by RNA-sequencing analysis, respectively. Enrichment analysis indicated that DEGs were enriched in the GO terms of cell-cell signalling and cell junctions. The pathways that regulate the development of follicles were identified, including the biological progress of cAMP accumulation, ovulation cycle and vasculature that are essential to follicular selection. 3. The results suggested that GnRH might directly regulate GC proliferation via autocrine or paracrine pathways related to cell junctions. In particular, it was confirmed that the mRNA and protein expression levels of the oestrogen receptor 2 (ESR2) gene, a negative transcription factor involved in follicular maturation and ovulation, were affected by GnRH agonist or antagonist in GCs. 4. In conclusion, GnRH might play an important role in follicular development by changing the expression of genes that participate in cAMP accumulation, ovulation cycle and cell junctions in ovarian GCs.

Detection of hepatitis E virus genotypes 3 and 4 in donkeys in northern China

BACKGROUND

Hepatitis E virus (HEV) is the causative agent of acute self-limiting hepatitis in humans in developing countries. Hepatitis E virus RNA was first detected in donkeys in Spain, but little is known about the possible presence of HEV in donkeys in China.

OBJECTIVES

To investigate the prevalence of HEV in donkeys in northern China.

STUDY DESIGN

Investigation of the prevalence of HEV in donkeys using serological, molecular and phylogenetic approaches.

METHODS

A total of 401 donkey serum specimens were tested for serological and molecular detection of HEV via enzyme-linked immunosorbent assay and quantitative reverse transcription polymerase chain reaction. The amplified products were cloned in pMD18-T vector and sequenced. The alignment and phylogenetic analysis of partial HEV ORF2 genes were compared with the corresponding sequences of the obtained HEV representative strains.

RESULTS

Serological results showed that 49 donkeys (12.22%, 95% CI: 9.18-15.83%) were positive for anti-HEV-specific antibodies, and 17 donkeys (4.24%, 95% CI: 2.49-6.70%) were positive for HEV viral RNA. On the basis of sequence alignment and phylogenetic analysis, all isolated HEV strains belonged to genotype 3 (HEV-3) or HEV-4, sharing more than 76.2-96.3% identities with 67 other HEV representative strains of HEV-1 to HEV-8.

MAIN LIMITATIONS

Further studies about the prevalence of HEV in organs or faecal samples from donkeys are needed to evaluate the possible role of HEV reservoir and to determine the risk factors associated with the transmission of this zoonotic virus in donkeys in China.

CONCLUSIONS

This is the first report documenting the molecular analysis of donkey HEV strains worldwide and the serological evidence of HEV infection in donkeys in northern China. The results suggest that young donkeys are more susceptible to HEV infection compared with older donkeys. Further investigation is required to determine whether donkeys should be considered reservoirs for zoonotic HEV. The Summary is available in Chinese - see Supporting information.

The impact of NudCD1 on renal carcinoma cell proliferation, migration, and invasion

OBJECTIVE

Renal cell carcinoma (RCC) is the most common malignant tumor in the urogenital system. Its easily metastatic characteristics greatly reduce the postoperative survival rate. NudCD1, as a proto-oncogene, may be involved in the proliferation, migration, and invasion of renal cell carcinoma cell. This study intends to explore the expression of NudCD1 in renal cancer tissue and its effect on renal cell behavior.

PATIENTS AND METHODS

NudCD1 expression in RCC tissue was tested Western blot. The cellular localization of NudCD1 was detected by immunohistochemistry (IHC). NudCD1 highly expressed RCC cell line was selected. NudCD1 knockdown or overexpression was performed through cell transfection. Cell proliferation, migration, and invasion were assessed by MTT assay, wound scratch assay, and transwell assay, respectively.

RESULTS

NudCD1 mainly located in the cytoplasm and significantly upregulated in RCC tissue compared with adjacent normal control (p < 0.05). NudCD1 expressed highest in A498 cell line among several RCC cell lines. NudCD1 expression was positively correlated with cell proliferation, migration, and invasion in A498. NudCD1 may be treated as a key factor in regulating cell behavior.

CONCLUSIONS

NudCD1 significantly increased in RCC and was positively correlated with cell proliferation, migration, and invasion. It could be used as an indicator for the early screening and potential treatment target for RCC.