An IL-17A-centric response to Epstein-Barr virus DNA mediated by dendritic Cell-T cell interactions

Introduction: The Epstein-Barr virus has been associated with a considerable number of autoimmune diseases. We have previously demonstrated that EBV DNA enhances the production of IL-17A, a pro-inflammatory cytokine, via endosomal Toll-like receptor signalling. Methods: We used RNA-seq to analyze the transcriptional profile of mouse immune cells treated with EBV DNA. Results: We observed that EBV DNA upregulates an IL-17A-centric network of mediators. Ensemble Gene Set Enrichment Analysis (EGSEA) showed enriched expression of sets involved in inflammatory responses including IFNγ and TNF-α-associated pathways as well as proinflammatory diseases. On the other hand, while macrophages and B cells were somewhat able to induce an IL-17A response from T cells to EBV DNA, they were less potent than dendritic cells. EBV virions were also capable of eliciting the production of inflammatory mediators from dendritic cell-T cell cultures largely mirroring responses to the viral DNA. Conclusions: Given the wide prevalence of EBV in the population, our analyses reveal a network of mediators and cell types that may serve as therapeutic targets in a large proportion of people affected by autoimmune diseases.

Microarray Analysis of Novel Genes Involved in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is an epithelial cancer associated with Epstein-Barr virus. Despite NPC is a widespread malignancy, little is known about association of tumor growth with gene expression. This study is aimed to detect potential genes implicated in the molecular mechanism of NPC. To this end, we downloaded GSE12452, GSE53819 and GSE64634 libraries from GEO database. GEO2R interface was used to search for the differentially expressed genes (DEGs) with R and LIMMA software, which yielded the Venn diagrams of co-expressed genes. The GO and KEGG databases were used to find DEGs with up- and down-regulated expression. Then Cytoscape software constructed and analyzed the protein-protein interaction (PPI) networks corresponding to revealed DEGs, thereupon the hub genes were analyzed in tissues and cell cultures with qRT-PCR. This combined analysis yielded 483 co-expressed DEGs, including 258 DEGs with up-regulated expression and 225 DEGs with down-regulated expression, which are mainly implicated in the cell cycle, DNA replication, as well as in formation and maturation of extracellular vesicles and exosomes. In comparison with normal nasopharyngeal tissues of healthy persons, expression of CDK1 gene was down-regulated in NPC tissue; in contrast, expression of PCNA, MAD2L1, PRC1, CENPF, and ZWINT genes was up-regulated in the tumor. The genes PCNA, MAD2L1, and ZWINT were differently expressed in EBV+ and EBV- nasopharyngeal carcinoma cells. The use of bioinformatic methods to reveal and analyze the differences in gene expression between the normal and NPC tissues opens the vista to further progress in deciphering the molecular mechanisms of NPC formation and development.

[Persistence of Epstein-Barr virus antigens in gastric cancer: characteristic of inflammatory cellular reactions in tumor]

THE AIM OF THE STUDY

Is to establish the relationship between the persistence of viral antigens of the Epstein-Barr virus (EBV) and the cellular composition of the immune microenvironment of tumor tissue and the mucous membrane of peritumoral area in gastric cancer.

MATERIAL AND METHODS

We used samples of surgical material from 55 patients with a verified diagnosis of gastric cancer. The expression of CD4, CD8, CD68, CD1a and LMP-1 was assessed. The results were assessed by the morphometric method. We selected three fields of view (magnification x200) in tumor tissue and in peritumoral areas separately and counted an absolute number of cells with positive staining with further calculation of the average number of cells and the median.

RESULTS

LMP-1-negative tumors with LMP-1 expression in epithelium of peritumoral area were characterized by the highest density of CD4+ lymphocyte infiltration in the central part of the tumor; the highest density of CD8+ lymphocyte infiltration in the mucous membrane of peritumoral area (p=0.0190); the highest density of infiltration by macrophages in the mucous membrane of peritumoral area (p=0.2492); the highest density of infiltration by CD1a+ cells in the mucous membrane of peritumoral area (p=0.1503). The highest density of infiltration with CD1a+ cells was characteristic for LMP-1-positive and LMP-1-negative tumors (p=0.0813). The persistence of the LMP-1 viral antigen in the glandular epithelium of the peritumoral area in our sample does not have a statistically significant effect on the prognosis of the disease (RR=1.7718; p=0.0885) but there is a tendency towards a negative predictive value.

CONCLUSION

High density of infiltration of glandular epithelium of peritumoral area with the expression of LMP-1 by CD4+ and CD8+ lymphocytes is most likely associated with the activation of the cellular immune response and may be one of the signs of the persistence of viral antigens. It was shown for the first time that the phenomenon of persistence of the LMP-1 viral antigen is characterized by a trend towards negative predictive value for patients with gastric cancer.

[Epstein-Barr virus-associated gastric adenocarcinoma]

EBV-associated gastric adenocarcinoma accounts for 10% of all gastric adenocarcinomas. The main known facts about the pathogenesis of EBV-associated gastric adenocarcinoma are presented. There are two main morphological types: gastric carcinoma with lymphoid stroma - GCLS (including lymphoepithelioma-like carcinoma; carcinoma with Crohn's disease-like lymphoid reaction; EBV-associated carcinoma with osteoclast-like giant cells) and conventional type adenocarcinoma. EBV-associated gastric adenocarcinomas predominantly express markers of gastric differentiation (MUC5AC, MUC6, CLDN-18) and a number of viral markers (EBER-1, EBNA-1 and BART mRNA). Three types of EBV latent cycle depending on the set of expressed viral transcripts are distinguished. It is believed that EBV-associated gastric adenocarcinoma is characterized by an intermediate position between latent cycles of types 1 and 2. The main method of virus identification is in situ hybridization with the detection of Epstein-Barr virus-encoded small RNAs (EBER-ISH).

[Human papillomavirus and Epstein-Barr virus in the pathogenesis of inverted papilloma and associated sinonasal carcinoma]

OBJECTIVE

To determine whether Epstein-Barr virus and human papillomavirus (HPV) types 6, 11, 16, 18, 35, and 43 DNA can be present in inverted papilloma (IP) and associated sinonasal carcinoma.

MATERIAL AND METHODS

The investigation was carried out using tissue samples obtained during surgery from 76 cases of IP and 4 cases of sinonasal carcinoma that had developed in the presence of IP. PCR was performed in 41 cases of IP and in 4 cases of sinonasal carcinoma; immunohistochemistry was done in 15 cases of IP to identify HPV L1 capsid protein.

RESULTS

HPV6 DNA was detected in 20 cases; three of them were simultaneously found to have also HPV11; 1 case had only HPV11. HPV types 16, 18, 35, and 45 and Epstein-Barr virus were not detected. PCR revealed HPV types 16 and 35 in one of the 4 cases of sinonasal carcinoma associated with IP. Immunohistochemical study identified HPV L1 capsid protein in the epitheliocytes and stromal infiltrating lymphocytes and macrophages in two cases of IP with the highest concentration of HPV DNA as evidenced by PCR, as well as in one case of sinonasal carcinoma.

CONCLUSION

Taking into account the low HPV DNA concentration detected only for types 6 and 11, as well as the immunohistochemical detection of HPV L1 in the tumor stromal lymphocytes and macrophages and some basal epitheliocytes in individual cases, it can be assumed that HPV does not play a crucial role as an etiological factor for IP. PCR revealed oncogenic HPV types 16 and 35 in sinonasal carcinoma associated with IP only in one case, which makes it untimely to claim that this virus plays a very special role in the etiology of this carcinoma. Epstein-Barr virus was not found in any case.

[Morphological diagnosis of viral damage to a kidney transplant]

Due to the development of organ transplantation and its accompanying immunosuppression, recent years have been marked by the higher incidence of opportunistic viral infections that are of considerable importance among posttransplantation complications. A variety of viral infections, the possibility of their concomitant or subtle course, and the ability to cause life-threatening complications in recipients make relevant the description of existing diagnostic methods. The article summarizes the data available in the literature on the etiology, clinical symptoms, and morphological manifestations of viral infections, such as polyomaviruses, adenoviruses, herpesviruses, including HSV-1, HSV-2, cytomegalovirus (CMV), and Epstein-Barr virus. It describes the principles of differential diagnosis of kidney transplant damage caused by these viruses and that with acute cellular and humoral rejection, which plays an important role due to opposite approaches to treating these diseases.