PXD028646

PXD028646 is an original dataset announced via ProteomeXchange.

Title	Epstein-Barr Virus+ B Cells in the Breast Cancer Immune Response: A Case Report.
Description	Tumor-Infiltrating Lymphocytes (TILs) are composed by several immune subpopulations including NK, NKT, Tab, Tgd and B cells. Although some of these cells can have antitumoral activities, there is also a large number of cells which are not tumor-specific,known as bystander cells. These cells may not have a direct role in the antitumoral response but could lead to a modulation of the immune response after time. Recent studies have described fatal encephalitis and myocarditis in cancer patients after immune checkpoint therapies, in which EBV-specific T cells may be involved. Since EBV is able to infect B cells and epithelial cells, both present in the primary tumor site, the first events of these fatal responses could be a consequence of a dysregulation of the immune system in the tumor microenvironment, although this have not been deeply studied. Thus, the main objectives of this study are (i) to use EBV-transformed B cells from the tumor site as a model to study the tumor-infiltrating EBV+ B cells and (ii) to use these EBV-derived B cells to study the relationship with autologous T cells isolated from the tumor site. T cells from TILs have been isolated from a triple negative breast cancer patient before neoadjuvancy and were expanded directly from the biopsy. A Patient-Derived Xenograft (PDX) generated from the breast tumor, progressed into a lymphocytic neoplasm. EBVtransformed B cells were obtained from this PDX (PDX-derived B cells). T Cell Receptor high-throughput sequencing has been used to monitor the clonotypes present in the different samples. We have found 43 clonotypes infiltrating the PDX-562 tissue and 18 of them were also present in the human biopsy or in the biopsy-derived T cell cultures. 5 of these sequences were found in one of the biopsy-derived T cells analyzed. Thus, PDXderived B cells have been used as antigen presenting cells to expand these cells. Few clonotypes were obtained after expansions, although the analysis of the middle CDR3 have revealed a similar pattern with the 18 sequences from the PDX sample. Furthermore, peptides presented by HLA have been eluted from PDX-derived B cells, followed by MS analysis. Peptides obtained derived from 31 different proteins and >40% are cancerrelated in terms of expression.
HostingRepository	PRIDE
AnnounceDate	2021-11-17
AnnouncementXML	Submission_2021-11-17_06:35:51.484.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Montserrat Carrascal
SpeciesList	scientific name: Homo sapiens (Human); NCBI TaxID: 9606;
ModificationList	No PTMs are included in the dataset
Instrument	LTQ Orbitrap

Revision	Datetime	Status	ChangeLog Entry
0	2021-09-20 02:50:21	ID requested
⏵ 1	2021-11-17 06:35:51	announced

Dataset with its publication pending

submitter keyword: tumor-infiltrating EBV+ B cells, immunopeptidomics, TCR, cancer, TILs

Mercè Martí
contact affiliation	Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallés, Barcelona, Spain.
contact email	Merce.Marti@uab.cat
lab head
Montserrat Carrascal
contact affiliation	IIBB-CSIC
contact email	montserrat.carrascal.csic@uab.cat
dataset submitter

Dataset FTP location NOTE: Most web browsers have now discontinued native support for FTP access within the browser window. But you can usually install another FTP app (we recommend FileZilla) and configure your browser to launch the external application when you click on this FTP link. Or otherwise, launch an app that supports FTP (like FileZilla) and use this address: ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2021/11/PXD028646

PRIDE project URI

• PRIDE
  1. PXD028646
     1. Label: PRIDE project
     2. Name: Epstein-Barr Virus+ B Cells in the Breast Cancer Immune Response: A Case Report.