Single-Cell Transcriptomic Analysis of Tumor-Derived Fibroblasts and Normal Tissue-Resident Fibroblasts Reveals Fibroblast Heterogeneity in Breast Cancer

Cancer-associated fibroblasts (CAFs) are a prominent stromal cell type in solid tumors and molecules secreted by CAFs play an important role in tumor progression and metastasis. CAFs coexist as heterogeneous populations with potentially different biological functions. Although CAFs are a major component of the breast cancer stroma, molecular and phenotypic heterogeneity of CAFs in breast cancer is poorly understood. In this study, we investigated CAF heterogeneity in triple-negative breast cancer (TNBC) using a syngeneic mouse model, BALB/c-derived 4T1 mammary tumors. Using single-cell RNA sequencing (scRNA-seq), we identified six CAF subpopulations in 4T1 tumors including: 1) myofibroblastic CAFs, enriched for α-smooth muscle actin and several other contractile proteins; 2) ‘inflammatory’ CAFs with elevated expression of inflammatory cytokines; and 3) a CAF subpopulation expressing major histocompatibility complex (MHC) class II proteins that are generally expressed in antigen-presenting cells. Comparison of 4T1-derived CAFs to CAFs from pancreatic cancer revealed that these three CAF subpopulations exist in both tumor types. Interestingly, cells with inflammatory and MHC class II-expressing CAF profiles were also detected in normal breast/pancreas tissue, suggesting that these phenotypes are not tumor microenvironment-induced. This work enhances our understanding of CAF heterogeneity, and specifically targeting these CAF subpopulations could be an effective therapeutic approach for treating highly aggressive TNBCs.

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Single cell RNA sequencing of blood antigen-presenting cells in severe Covid-19 reveals multi-process defects in antiviral immunity

10.1101/2020.07.20.212837 ◽

2020 ◽

Author(s):

Melissa Saichi ◽

Maha Zohra Ladjemi ◽

Sarantis Korniotis ◽

Christophe Rousseau ◽

Zakaria Ait-Hamou ◽

...

Keyword(s):

Single Cell ◽

Rna Sequencing ◽

Mhc Class Ii ◽

Antigen Presenting Cells ◽

Antiviral Immunity ◽

Class Ii ◽

Immune Defense ◽

Simultaneous Increase ◽

Single Cell Rna Sequencing ◽

Antigen Presenting

AbstractCOVID-19 can lead to life-threatening acute respiratory failure, characterized by simultaneous increase in inflammatory mediators and viral load. The underlying cellular and molecular mechanisms remain unclear. We performed single-cell RNA-sequencing to establish an exhaustive high-resolution map of blood antigen-presenting cells (APC) in 7 COVID-19 patients with moderate or severe pneumonia, at day-1 and day-4 post-admission, and two healthy donors. We generated a unique dataset of 31,513 high quality APC, including monocytes and rare dendritic cell (DC) subsets. We uncovered multiprocess and previously unrecognized defects in anti-viral immune defense in specific APC compartments from severe patients: i) increase of pro-apoptotic genes exclusively in pDC, which are key effectors of antiviral immunity, ii) sharp decrease of innate sensing receptors, TLR7 and DHX9, in pDC and cDC1, respectively, iii) down-regulation of antiviral effector molecules, including Interferon stimulated genes (ISG) in all monocyte subsets, and iv) decrease of MHC class II-related genes, and MHC class II transactivator (CIITA) activity in cDC2, suggesting a viral inhibition of antigen presentation. These novel mechanisms may explain patient aggravation and suggest strategies to restore defective immune defense.

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Allotransplantation of culture-isolated neonatal rat islet tissue. Absence of MHC class II positive antigen-presenting cells in nonimmunogenic islets

Diabetes ◽

10.2337/diabetes.38.2.146 ◽

1989 ◽

Vol 38 (2) ◽

pp. 146-151 ◽

Cited By ~ 1

Author(s):

O. D. Hegre ◽

R. J. Ketchum ◽

H. Popiela ◽

C. R. Eide ◽

R. M. Meloche ◽

...

Keyword(s):

Mhc Class Ii ◽

Antigen Presenting Cells ◽

Class Ii ◽

Neonatal Rat ◽

Islet Tissue ◽

Antigen Presenting

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Immunohistochemical Characterization and Localization of MHC Class II Antigen-Presenting Cells in the Periodontal Ligament of Rat Incisors

Connective Tissue Research ◽

10.3109/03008209509016980 ◽

1995 ◽

Vol 33 (1-3) ◽

pp. 47-56 ◽

Cited By ~ 3

Author(s):

Ichiro Kawahara ◽

Yoshiro Takano

Keyword(s):

Mhc Class Ii ◽

Periodontal Ligament ◽

Antigen Presenting Cells ◽

Class Ii ◽

Class Ii Antigen ◽

Antigen Presenting ◽

Mhc Class Ii Antigen

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Major Histocompatibility Complex Class II+ Invariant Chain Negative Breast Cancer Cells Present Unique Peptides that Activate Tumor-specific T Cells from Breast Cancer Patients

Molecular & Cellular Proteomics ◽

10.1074/mcp.m112.019232 ◽

2012 ◽

Vol 11 (11) ◽

pp. 1457-1467 ◽

Cited By ~ 12

Author(s):

Olesya Chornoguz ◽

Alexei Gapeev ◽

Michael C. O'Neill ◽

Suzanne Ostrand-Rosenberg

Keyword(s):

Breast Cancer ◽

T Cells ◽

Cancer Cells ◽

Cancer Patients ◽

Mhc Class Ii ◽

Breast Cancer Cells ◽

Class Ii ◽

Breast Cancer Patients ◽

Mhc Ii ◽

Peptide Loading

The major histocompatibility complex (MHC) class II-associated Invariant chain (Ii) is present in professional antigen presenting cells where it regulates peptide loading onto MHC class II molecules and the peptidome presented to CD4+ T lymphocytes. Because Ii prevents peptide loading in neutral subcellular compartments, we reasoned that Ii− cells may present peptides not presented by Ii+ cells. Based on the hypothesis that patients are tolerant to MHC II-restricted tumor peptides presented by Ii+ cells, but will not be tolerant to novel peptides presented by Ii− cells, we generated MHC II vaccines to activate cancer patients' T cells. The vaccines are Ii− tumor cells expressing syngeneic HLA-DR and the costimulatory molecule CD80. We used liquid chromatography coupled with mass spectrometry to sequence MHC II-restricted peptides from Ii+ and Ii− MCF10 human breast cancer cells transfected with HLA-DR7 or the MHC Class II transactivator CIITA to determine if Ii− cells present novel peptides. Ii expression was induced in the HLA-DR7 transfectants by transfection of Ii, and inhibited in the CIITA transfectants by RNA interference. Peptides were analyzed and binding affinity predicted by artificial neural net analysis. HLA-DR7-restricted peptides from Ii− and Ii+ cells do not differ in size or in subcellular location of their source proteins; however, a subset of HLA-DR7-restricted peptides of Ii− cells are not presented by Ii+ cells, and are derived from source proteins not used by Ii+ cells. Peptides from Ii− cells with the highest predicted HLA-DR7 binding affinity were synthesized, and activated tumor-specific HLA-DR7+ human T cells from healthy donors and breast cancer patients, demonstrating that the MS-identified peptides are bonafide tumor antigens. These results demonstrate that Ii regulates the repertoire of tumor peptides presented by MHC class II+ breast cancer cells and identify novel immunogenic MHC II-restricted peptides that are potential therapeutic reagents for cancer patients.

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Hierarchy of Susceptibility of Dendritic Cell Subsets to Infection by Leishmania major: Inverse Relationship to Interleukin-12 Production

Infection and Immunity ◽

10.1128/iai.70.7.3874-3880.2002 ◽

2002 ◽

Vol 70 (7) ◽

pp. 3874-3880 ◽

Cited By ~ 31

Author(s):

Sandrine Henri ◽

Joan Curtis ◽

Hubertus Hochrein ◽

David Vremec ◽

Ken Shortman ◽

...

Keyword(s):

Immune Responses ◽

Mhc Class Ii ◽

Leishmania Major ◽

Parasitophorous Vacuole ◽

Class Ii ◽

Host Cells ◽

Interleukin 12 ◽

Histocompatibility Complex ◽

T Cell Immune Responses ◽

Antigen Presenting

ABSTRACT Dendritic cells (DCs) are professional antigen-presenting cells which initiate and regulate T-cell immune responses. Here we show that murine splenic DCs can be ranked on the basis of their ability to phagocytose and harbor the obligately intracellular parasite Leishmania major. CD4+ CD8− DCs are the most permissive host cells for L. major amastigotes, followed by CD4− CD8− DCs; CD4− CD8+ cells are the least permissive. However, the least susceptible CD4− CD8+ DC subset was the best interleukin-12 producer in response to infection. Infection did not induce in any DC subset production of the proinflammatory cytokine gamma interferon and nitric oxide associated with the induction of Th1 responses. The number of parasites phagocytosed by DCs was low, no more than 3 organisms per cell, compared to more than 10 organisms per macrophage. In infected DCs, the parasites are located in a parasitophorous vacuole containing both major histocompatibility complex (MHC) class II and lysosome-associated membrane protein 1 molecules, similar to their location in the infected macrophage. The parasite-driven redistribution of MHC class II to this compartment indicates that infected DCs should be able to present parasite antigen.

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Stratification of Antigen-presenting Cells within the Normal Cornea

Ophthalmology and Eye Diseases ◽

10.4137/oed.s2813 ◽

2009 ◽

Vol 1 ◽

pp. OED.S2813 ◽

Cited By ~ 44

Author(s):

Jared E. Knickelbein ◽

Simon C. Watkins ◽

Paul G. Mcmenamin ◽

Robert L. Hendricks

Keyword(s):

Bone Marrow ◽

Basement Membrane ◽

Mhc Class Ii ◽

Fluorescent Protein ◽

Antigen Presenting Cells ◽

Class Ii ◽

Apical Surface ◽

Bone Marrow Derived Cells ◽

Green Fluorescent ◽

Antigen Presenting

The composition and location of professional antigen presenting cells (APC) varies in different mucosal surfaces. The cornea, long considered an immune-privileged tissue devoid of APCs, is now known to host a heterogeneous network of bone marrow-derived cells. Here, we utilized transgenic mice that express enhanced green fluorescent protein (EGFP) from the CD 11c promoter (pCD11c) in conjunction with immunohistochemical staining to demonstrate an interesting stratification of APCs within non-inflamed murine corneas. pCD11c+ dendritic cells (DCs) reside in the basal epithelium, seemingly embedded in the basement membrane. Most DCs express MHC class II on at least some dendrites, which extend up to 50 μm in length and traverse up 20 μm tangentially towards the apical surface of the epithelium. The DC density diminishes from peripheral to central cornea. Beneath the DCs and adjacent to the stromal side of the basement membrane reside pCD11c–CD11b+ putative macrophages that express low levels of MHC class II. Finally, MHC class II–pCD11c–CD11b+ cells form a network throughout the remainder of the stroma. This highly reproducible stratification of bone marrow-derived cells is suggestive of a progression from an APC function at the exposed corneal surface to an innate immune barrier function deeper in the stroma.

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Small amounts of superantigen, when presented on dendritic cells, are sufficient to initiate T cell responses.

Journal of Experimental Medicine ◽

10.1084/jem.178.2.633 ◽

1993 ◽

Vol 178 (2) ◽

pp. 633-642 ◽

Cited By ~ 91

Author(s):

N Bhardwaj ◽

J W Young ◽

A J Nisanian ◽

J Baggers ◽

R M Steinman

Keyword(s):

T Cells ◽

Dendritic Cells ◽

T Cell ◽

Dendritic Cell ◽

Mhc Class Ii ◽

Cell Receptor ◽

Class Ii ◽

Cell Mediated Immunity ◽

Quiescent T Cells ◽

Antigen Presenting

Dendritic cells are potent antigen-presenting cells for several primary immune responses and therefore provide an opportunity for evaluating the amounts of cell-associated antigens that are required for inducing T cell-mediated immunity. Because dendritic cells express very high levels of major histocompatibility complex (MHC) class II products, it has been assumed that high levels of ligands bound to MHC products ("signal one") are needed to stimulate quiescent T cells. Here we describe quantitative aspects underlying the stimulation of human blood T cells by a bacterial superantigen, staphylococcal enterotoxin A (SEA). The advantages of superantigens for quantitative studies of signal one are that these ligands: (a) engage MHC class II and the T cell receptor but do not require processing; (b) are efficiently presented to large numbers of quiescent T cells; and (c) can be pulsed onto dendritic cells before their application to T cells. Thus one can relate amounts of dendritic cell-associated SEA to subsequent lymphocyte stimulation. Using radioiodinated SEA, we noted that dendritic cells can bind 30-200 times more superantigen than B cells and monocytes. Nevertheless, this high SEA binding does not underlie the strong potency of dendritic cells to present antigen to T cells. Dendritic cells can sensitize quiescent T cells, isolated using monoclonals to appropriate CD45R epitopes, after a pulse of SEA that occupies a maximum of 0.1% of surface MHC class II molecules. This corresponds to an average of 2,000 molecules per dendritic cell. At these low doses of bound SEA, monoclonal antibodies to CD3, CD4, and CD28 almost completely block T cell proliferation. In addition to suggesting new roles for MHC class II on dendritic cells, especially the capture and retention of ligands at low external concentrations, the data reveal that primary T cells can generate a response to exceptionally low levels of signal one as long as these are delivered on dendritic cells.

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Impact of negatively charged patches on the surface of MHC class II antigen-presenting proteins on risk of chronic beryllium disease

Journal of The Royal Society Interface ◽

10.1098/rsif.2007.1223 ◽

2007 ◽

Vol 5 (24) ◽

pp. 749-758 ◽

Cited By ~ 20

Author(s):

James A Snyder ◽

Eugene Demchuk ◽

Erin C McCanlies ◽

Christine R Schuler ◽

Kathleen Kreiss ◽

...

Keyword(s):

Glutamic Acid ◽

Mhc Class Ii ◽

Protein Interactions ◽

Class Ii ◽

Chronic Beryllium Disease ◽

Glutamic Acid Residue ◽

The One ◽

Class Ii Antigen ◽

Antigen Presenting ◽

Beryllium Disease

Chronic beryllium disease (CBD) is a granulomatous lung disease that occurs primarily in workers who are exposed to beryllium dust or fumes. Although exposure to beryllium is a necessary factor in the pathobiology of CBD, alleles that code for a glutamic acid residue at the 69th position of the HLA-DPβ1 gene have previously been found to be associated with CBD. To date, 43 HLA-DPβ1 alleles that code for glutamic acid 69 (E69) have been described. Whether all of these E69 coding alleles convey equal risk of CBD is unknown. The present study demonstrates that, on the one hand, E69 alleloforms of major histocompatibility complex class II antigen-presenting proteins with the greatest negative surface charge convey the highest risk of CBD, and on the other hand, irrespective of allele, they convey equal risk of beryllium sensitization (BeS). In addition, the data suggest that the same alleles that cause the greatest risk of CBD are also important for the progression from BeS to CBD. Alleles convey the highest risk code for E26 in a constant region and for E69, aspartic acid 55 (D55), E56, D84 and E85 in hypervariable regions of the HLA-DPβ1 chain. Together with the calculated high binding affinities for beryllium, these results suggest that an adverse immune response, leading to CBD, is triggered by chemically specific metal–protein interactions.

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