Epigenetic control of MHC class II expression in tumor-associated macrophages by decoy receptor 3

Blood ◽  
2008 ◽  
Vol 111 (10) ◽  
pp. 5054-5063 ◽  
Author(s):  
Yung-Chi Chang ◽  
Tse-Ching Chen ◽  
Chun-Ting Lee ◽  
Chih-Ya Yang ◽  
Hsei-Wei Wang ◽  
...  
Keyword(s):  
Antigen Presentation ◽  
Mhc Class Ii ◽  
Malignant Tumors ◽  
Class Ii ◽  
Tumor Associated Macrophages ◽  
Class Ii Transactivator ◽  
Decoy Receptor ◽  
Mhc Ii ◽  
Hla Dr ◽  
Decoy Receptor 3

Abstract Decoy receptor 3 (DcR3) is a member of the TNF receptor superfamily and is up-regulated in tumors originating from a diversity of lineages. DcR3 is capable of promoting angiogenesis, inducing dendritic cell apoptosis, and modulating macrophage differentiation. Since tumor-associated macrophages (TAMs) are the major infiltrating leukocytes in most malignant tumors, we used microarray technology to investigate whether DcR3 contributes to the development of TAMs. Among the DcR3-modulated genes expressed by TAMs, those that encode proteins involved in MHC class II (MHC-II)–dependent antigen presentation were down-regulated substantially, together with the master regulator of MHC-II expression (the class II transactivator, CIITA). The ERK- and JNK-induced deacetylation of histones associated with the CIITA promoters was responsible for DcR3-mediated down-regulation of MHC-II expression. Furthermore, the expression level of DcR3 in cancer cells correlated inversely with HLA-DR levels on TAMs and with the overall survival time of pancreatic cancer patients. The role of DcR3 in the development of TAMs was further confirmed using transgenic mice overexpressing DcR3. This elucidates the molecular mechanism of impaired MHC-II–mediated antigen presentation by TAMs, and raises the possibility that subversion of TAM-induced immunosuppression via inhibition of DcR3 expression might represent a target for the design of new therapeutics.

scholarly journals Human Cytomegalovirus Decreases Major Histocompatibility Complex Class II by Regulating Class II Transactivator Transcript Levels in a Myeloid Cell Line

2020 ◽  
Vol 94 (7) ◽  
Author(s):  
Praneet K. Sandhu ◽  
Nicholas J. Buchkovich
Keyword(s):  
Mhc Class Ii ◽  
Human Cytomegalovirus ◽  
Class Ii ◽  
T Cell Response ◽  
Class Ii Transactivator ◽  
Myeloid Progenitor ◽  
Histocompatibility Complex ◽  
Hla Dr ◽  
Myeloid Progenitor Cell ◽  
Infected Cells

ABSTRACT Human cytomegalovirus (HCMV) is a ubiquitous pathogen that encodes many proteins to modulate the host immune response. Extensive efforts have led to the elucidation of multiple strategies employed by HCMV to effectively block NK cell targeting of virus-infected cells and the major histocompatibility complex (MHC) class I-primed CD8+ T cell response. However, viral regulation of the MHC class II-mediated CD4+ T cell response is understudied in endogenous MHC class II-expressing cells, largely because the popular cell culture systems utilized for studying HCMV do not endogenously express MHC class II. Of the many cell types infected by HCMV in the host, myeloid cells, such as monocytes, are of particular importance due to their role in latency and subsequent dissemination throughout the host. We investigated the impact of HCMV infection on MHC class II in Kasumi-3 cells, a myeloid-progenitor cell line that endogenously expresses the MHC class II gene, HLA-DR. We observed a significant reduction in the expression of surface and total HLA-DR at 72 h postinfection (hpi) and 120 hpi in infected cells. The decrease in HLA-DR expression was independent of the expression of previously described viral genes that regulate the MHC class II complex or the unique short (US) region of HCMV, a region expressing many immunomodulatory genes. The altered surface level of HLA-DR was not a result of increased endocytosis and degradation but was a result of a reduction in HLA-DR transcripts due to a decrease in the expression of the class II transactivator (CIITA). IMPORTANCE Human cytomegalovirus (HCMV) is an opportunistic herpesvirus that is asymptomatic for healthy individuals but that can lead to severe pathology in patients with congenital infections and immunosuppressed patients. Thus, it is important to understand the modulation of the immune response by HCMV, which is understudied in the context of endogenous MHC class II regulation. Using Kasumi-3 cells as a myeloid progenitor cell model endogenously expressing MHC class II (HLA-DR), this study shows that HCMV decreases the expression of HLA-DR in infected cells by reducing the transcription of HLA-DR transcripts early during infection independently of the expression of previously implicated genes. This is an important finding, as it highlights a mechanism of immune evasion utilized by HCMV to decrease the expression of MHC class II in a relevant cell system that endogenously expresses the MHC class II complex.

scholarly journals The MHC Class II Transactivator CIITA: Not (Quite) the Odd-One-Out Anymore among NLR Proteins

2021 ◽  
Vol 22 (3) ◽  
pp. 1074
Author(s):  
Jorge Alfonso León Machado ◽  
Viktor Steimle
Keyword(s):  
Gene Expression ◽  
Mhc Class Ii ◽  
Protein Interactions ◽  
Transcriptional Regulator ◽  
Class Ii ◽  
Class Ii Transactivator ◽  
Mhc I ◽  
Mhc Ii ◽  
Mhc Class Ii Transactivator

In this review, we discuss the major histocompatibility complex (MHC) class II transactivator (CIITA), which is the master regulator of MHC class II gene expression. CIITA is the founding member of the mammalian nucleotide-binding and leucine-rich-repeat (NLR) protein family but stood apart for a long time as the only transcriptional regulator. More recently, it was found that its closest homolog, NLRC5 (NLR protein caspase activation and recruitment domain (CARD)-containing 5), is a regulator of MHC-I gene expression. Both act as non-DNA-binding activators through multiple protein–protein interactions with an MHC enhanceosome complex that binds cooperatively to a highly conserved combinatorial cis-acting module. Thus, the regulation of MHC-II expression is regulated largely through the differential expression of CIITA. In addition to the well-defined role of CIITA in MHC-II GENE regulation, we will discuss several other aspects of CIITA functions, such as its role in cancer, its role as a viral restriction element contributing to intrinsic immunity, and lastly, its very recently discovered role as an inhibitor of Ebola and SARS-Cov-2 virus replication. We will briefly touch upon the recently discovered role of NLRP3 as a transcriptional regulator, which suggests that transcriptional regulation is, after all, not such an unusual feature for NLR proteins.

scholarly journals Inhibition of HLA-DR Assembly, Transport, and Loading by Human Cytomegalovirus Glycoprotein US3: a Novel Mechanism for Evading Major Histocompatibility Complex Class II Antigen Presentation

2002 ◽  
Vol 76 (21) ◽  
pp. 10929-10941 ◽  
Author(s):  
Nagendra R. Hegde ◽  
Roman A. Tomazin ◽  
Todd W. Wisner ◽  
Claire Dunn ◽  
Jessica M. Boname ◽  
...  
Keyword(s):  
T Cells ◽  
Major Histocompatibility Complex ◽  
Antigen Presentation ◽  
Class Ii ◽  
Complex Class ◽  
Mhc Ii ◽  
Histocompatibility Complex ◽  
Hla Dr ◽  
Antigen Presentation Pathway ◽  
Presentation Pathway

ABSTRACT Human cytomegalovirus (HCMV) establishes persistent lifelong infections and replicates slowly. To withstand robust immunity, HCMV utilizes numerous immune evasion strategies. The HCMV gene cassette encoding US2 to US11 encodes four homologous glycoproteins, US2, US3, US6, and US11, that inhibit the major histocompatibility complex class I (MHC-I) antigen presentation pathway, probably inhibiting recognition by CD8+ T lymphocytes. US2 also inhibits the MHC-II antigen presentation pathway, causing degradation of human leukocyte antigen (HLA)-DR-α and -DM-α and preventing recognition by CD4+ T cells. We investigated the effects of seven of the US2 to US11 glycoproteins on the MHC-II pathway. Each of the glycoproteins was expressed by using replication-defective adenovirus vectors. In addition to US2, US3 inhibited recognition of antigen by CD4+ T cells by a novel mechanism. US3 bound to class II α/β complexes in the endoplasmic reticulum (ER), reducing their association with Ii. Class II molecules moved normally from the ER to the Golgi apparatus in US3-expressing cells but were not sorted efficiently to the class II loading compartment. As a consequence, formation of peptide-loaded class II complexes was reduced. We concluded that US3 and US2 can collaborate to inhibit class II-mediated presentation of endogenous HCMV antigens to CD4+ T cells, allowing virus-infected cells to resist recognition by CD4+ T cells.

scholarly journals Alphaherpesvirus gB Homologs Are Targeted to Extracellular Vesicles, but They Differentially Affect MHC Class II Molecules

Viruses ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 429 ◽  
Author(s):  
Kinga Grabowska ◽  
Magda Wąchalska ◽  
Małgorzata Graul ◽  
Michał Rychłowski ◽  
Krystyna Bieńkowska-Szewczyk ◽  
...  
Keyword(s):  
Cell Lines ◽  
Mhc Class Ii ◽  
Differential Effect ◽  
Pseudorabies Virus ◽  
Class Ii ◽  
Stable Cell Lines ◽  
Mhc Ii ◽  
Hla Dr ◽  
Infected Cells ◽  
Hsv 1

Herpesvirus envelope glycoprotein B (gB) is one of the best-documented extracellular vesicle (EVs)-incorporated viral proteins. Regarding the sequence and structure conservation between gB homologs, we asked whether bovine herpesvirus-1 (BoHV-1) and pseudorabies virus (PRV)-encoded gB share the property of herpes simplex-1 (HSV-1) gB to be trafficked to EVs and affect major histocompatibility complex (MHC) class II. Our data highlight some conserved and differential features of the three gBs. We demonstrate that mature, fully processed BoHV-1 and PRV gBs localize to EVs isolated from constructed stable cell lines and EVs-enriched fractions from virus-infected cells. gB also shares the ability to co-localize with CD63 and MHC II in late endosomes. However, we report here a differential effect of the HSV-1, BoHV-1, and PRV glycoprotein on the surface MHC II levels, and MHC II loading to EVs in stable cell lines, which may result from their adverse ability to bind HLA-DR, with PRV gB being the most divergent. BoHV-1 and HSV-1 gB could retard HLA-DR exports to the plasma membrane. Our results confirm that the differential effect of gB on MHC II may require various mechanisms, either dependent on its complex formation or on inducing general alterations to the vesicular transport. EVs from virus-infected cells also contained other viral glycoproteins, like gD or gE, and they were enriched in MHC II. As shown for BoHV-1 gB- or BoHV-1-infected cell-derived vesicles, those EVs could bind anti-virus antibodies in ELISA, which supports the immunoregulatory potential of alphaherpesvirus gB.

Tuning DO:DM ratios modulates MHC class II immunopeptidomes

2021 ◽  
Author(s):  
Niclas E Olsson ◽  
Wei Jiang ◽  
Lital N Adler ◽  
Elizabeth Mellins ◽  
Joshua E Elias
Keyword(s):  
Antigen Presentation ◽  
Mhc Class Ii ◽  
Computational Prediction ◽  
Class Ii ◽  
The Body ◽  
Research Strategies ◽  
Mhc Ii ◽  
Wide Range ◽  
Health And Disease ◽  
Antigen Presenting

Major histocompatibility complex class II (MHC-II) antigen presentation underlies a wide range of immune responses in health and disease. However, how MHC-II antigen presentation is regulated by the peptide-loading catalyst HLA-DM (DM), its associated modulator, HLA-DO (DO), is incompletely understood. This is due largely to technical limitations: model antigen presenting cell (APC) systems that express these MHC-II peptidome regulators at physiologically variable levels have not been described. Likewise, computational prediction tools that account for DO and DM activities are not presently available. To address these gaps, we created a panel of single MHC-II allele, HLA-DR4-expressing APC lines that cover a wide range of DO:DM ratio states. Using a combined immunopeptidomic and proteomic discovery strategy, we measured the effects DO:DM ratios have on peptide presentation by surveying over 10,000 unique DR4-presented peptides. The resulting data provide insight into peptide characteristics that influence their presentation with increasing DO:DM ratios. These include DM-sensitivity, peptide abundance, binding affinity and motif, peptide length and register positioning on the source protein. These findings have implications for designing improved HLA-II prediction algorithms and research strategies for dissecting the variety of functions that different APCs serve in the body.

scholarly journals Ubiquitination by March-I prevents MHC class II recycling and promotes MHC class II turnover in antigen-presenting cells

2015 ◽  
Vol 112 (33) ◽  
pp. 10449-10454 ◽  
Author(s):  
Kyung-Jin Cho ◽  
Even Walseng ◽  
Satoshi Ishido ◽  
Paul A. Roche
Keyword(s):  
B Cells ◽  
Antigen Presentation ◽  
Mhc Class Ii ◽  
Antigen Presenting Cells ◽  
Class Ii ◽  
Mhc Ii ◽  
Class Ii Mhc ◽  
Subsequent Degradation ◽  
Antigen Presenting

MHC class II (MHC-II)-dependent antigen presentation by antigen-presenting cells (APCs) is carefully controlled to achieve specificity of immune responses; the regulated assembly and degradation of antigenic peptide–MHC-II complexes (pMHC-II) is one aspect of such control. In this study, we have examined the role of ubiquitination in regulating pMHC-II biosynthesis, endocytosis, recycling, and turnover in APCs. By using APCs obtained from MHC-II ubiquitination mutant mice, we find that whereas ubiquitination does not affect pMHC-II formation in dendritic cells (DCs), it does promote the subsequent degradation of newly synthesized pMHC-II. Acute activation of DCs or B cells terminates expression of the MHC-II E3 ubiquitin ligase March-I and prevents pMHC-II ubiquitination. Most importantly, this change results in very efficient pMHC-II recycling from the surface of DCs and B cells, thereby preventing targeting of internalized pMHC-II to lysosomes for degradation. Biochemical and functional assays confirmed that pMHC-II turnover is suppressed in MHC-II ubiquitin mutant DCs or by acute activation of wild-type DCs. These studies demonstrate that acute APC activation blocks the ubiquitin-dependent turnover of pMHC-II by promoting efficient pMHC-II recycling and preventing lysosomal targeting of internalized pMHC-II, thereby enhancing pMHC-II stability for efficient antigen presentation to CD4 T cells.

scholarly journals Class II transactivator regulates the expression of multiple genes involved in antigen presentation.

1995 ◽  
Vol 181 (2) ◽  
pp. 765-767 ◽  
Author(s):  
C H Chang ◽  
R A Flavell
Keyword(s):  
Antigen Presentation ◽  
Mhc Class Ii ◽  
Class Ii ◽  
Class Ii Transactivator ◽  
Leukocyte Antigen ◽  
Expression Of Genes ◽  
Mhc Class Ii Transactivator ◽  
Mutant Cells ◽  
Mhc Class Ii Genes

CIITA (a major histocompatibility complex [MHC] class II transactivator) has been shown to be required for the expression of MHC class II genes in both B cells and interferon gamma-inducible cells. Here we demonstrate that CIITA not only activates MHC class II genes but also genes required for antigen presentation. Mutant HeLa cells, defective in the expression of classic MHC class II genes, invariant chain, and the newly described human histocompatibility leukocyte antigen-DM genes, were used to study the role of CIITA in the regulation of these genes. Upon transfection with CIITA cDNA, the mutant cells expressed all three genes, suggesting that CIITA is a global regulator for the expression of genes involved in antigen presentation.

scholarly journals An Isotype-specific Activator of Major Histocompatibility Complex (MHC) Class II Genes That Is Independent of Class II Transactivator

1997 ◽  
Vol 185 (11) ◽  
pp. 1885-1895 ◽  
Author(s):  
John Douhan ◽  
Rebecca Lieberson ◽  
Joan H.M. Knoll ◽  
Hong Zhou ◽  
Laurie H. Glimcher
Keyword(s):  
Major Histocompatibility Complex ◽  
Cell Line ◽  
Mhc Class Ii ◽  
Ectopic Expression ◽  
Class Ii ◽  
Major Histocompatibility ◽  
Class Ii Transactivator ◽  
Histocompatibility Complex ◽  
Hla Dr ◽  
Hla Dq

Patients with one type of major histocompatibility complex class II combined immunodeficiency have mutations in a gene termed class II transactivator (CIITA), which coordinately controls the transcription of the three major human class II genes, HLA-DR, -DQ, and -DP. However, the experimentally derived B-lymphoblastoid cell line, clone 13, expresses high levels of HLADQ in the absence of HLA-DR and HLA-DP, despite its mapping by complementation analysis to this group. It was possible that one of the clone 13 CIITA alleles bore a mutation that allowed HLA-DQ, but not HLA-DR or -DP transcription. Alternatively, another factor, distinct from CIITA, might control HLA-DQ expression. We report here that ectopic expression of CIITA cDNAs derived by reverse transcriptase polymerase chain reaction from clone 13 do not restore expression of HLA-DQ in another CIITA-deficient cell line, RJ2.2.5. In addition, no CIITA protein is detectable in clone 13 nuclear extracts. In contrast, somatic cell fusion between clone 13 and RJ2.2.5 restored expression of the HLA-DQ haplotype encoded by the RJ2.2.5 DQB gene. Taken together, these data demonstrate the existence of an HLA-DQ isotype-specific trans-acting factor, which functions independently of CIITA.

Dendritic cells constitutively present self antigens in their immature state in vivo and regulate antigen presentation by controlling the rates of MHC class II synthesis and endocytosis

Blood ◽  
2004 ◽  
Vol 103 (6) ◽  
pp. 2187-2195 ◽  
Author(s):  
Nicholas S. Wilson ◽  
Dima El-Sukkari ◽  
José A. Villadangos
Keyword(s):  
Dendritic Cells ◽  
Antigen Presentation ◽  
Mhc Class Ii ◽  
Class Ii ◽  
Lymphoid Organ ◽  
Lymphoid Organs ◽  
Mhc Ii ◽  
Peptide Complexes ◽  
Self Antigens

Abstract Dendritic cells (DCs) change their antigen-presenting properties during maturation. Immature DCs efficiently capture antigens, but are reported to be impaired in their processing and presenting capacity. Upon an encounter with an inflammatory stimulus, DCs undergo a maturation process that leads to efficient presentation of antigens captured at the time of activation, but precludes processing of antigens encountered at later time points. The mechanisms that underlie these developmental changes are controversial. Thus, it is unclear whether immature DCs can present self antigens, and which are the checkpoints that regulate antigen presentation in immature and mature DCs. We have characterized these mechanisms using DCs derived directly from lymphoid organs. Immature lymphoid organ DCs constitutively presented self peptides bound to major histocompatibility complex class II (MHCII) molecules, but these MHCII-peptide complexes were degraded quickly after their transient expression on the cell surface. During maturation, MHC II endocytosis was down-regulated, so that newly generated MHC II–peptide complexes accumulated on the plasma membrane. Simultaneously, MHC II synthesis was down-regulated, thus preventing the turnover of the MHC II–peptide complexes that accumulated early during maturation. Our results demonstrate that immature DCs constitutively present self antigens in the lymphoid organs and characterize the molecular basis of the capacity of DCs to provide “antigenic memory” in vivo.

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