AP-1 complex activation is a conserved signature of immune system aging and a potential regulator of inflammaging in human and mice

Abstract Increased inflammation with age (i.e., inflammaging) is a hallmark of aging conserved in human and mice, but the underlying mechanisms are poorly understood, partially because a systematic comparative study of mouse and human immune system aging is lacking. We uncovered epigenomic/transcriptomic signatures of aging in spleen and peripheral blood lymphocytes from young (3 months) and old (18 months) mice in two strains: C57BL/6J (long-lived) and NZO/HILtJ (short-lived) and compared these to the aging signatures of human peripheral blood cells. The most predominant and conserved genomic signature of aging in human and mice tissues studied here was the epigenetic activation of several AP-1 complex members (Fos, Fosl2, Junb, Jund). Footprinting analyses showed that these transcription factors ‘bind’ more frequently with age and target pro-inflammatory and effector molecules, including the pro-inflammatory Il6. Analysis of single cell RNA-seq data from the mouse aging cell atlas (Tabula Muris Senis) revealed that AP-1 activation with age is a common feature across all immune cell types within spleens, yet macrophages express these molecules more often than other cells. Functional assays confirmed that spleen cells from older animals have increased c-JUN protein binding and increased IL6 production upon myeloid cell activation using poly(I:C) via TLR3. Western blot data revealed that c-JUN activation with age is not post-transcriptional since its phosphorylation levels were similar between young and old mice. Together, these data established that Jun and Fos families in the AP-1 complex are transcriptionally activated with age and target pro-inflammatory molecules and aging-related increases in the binding of these proteins likely modulate increased inflammation with age.

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Identification of a C3bi-specific membrane complement receptor that is expressed on lymphocytes, monocytes, neutrophils, and erythrocytes

Journal of Experimental Medicine ◽

10.1084/jem.155.1.96 ◽

1982 ◽

Vol 155 (1) ◽

pp. 96-110 ◽

Cited By ~ 112

Author(s):

GD Ross ◽

JD Lambris

Keyword(s):

Peripheral Blood ◽

Myeloid Cell ◽

Fluid Phase ◽

Cell Types ◽

Peripheral Blood Lymphocytes ◽

Polymorphonuclear Cells ◽

Coated Particles ◽

Blood Lymphocytes ◽

T Cell Antigens ◽

D Region

Cells expressing a membrane C receptor (CR(3)) specific for C3b-inactivator- cleaved C3b (C3bi) were identified by rosette assay with C3bi-coated sheep erythrocytes (EC3bi) or C3bi-coated fluorescent microspheres (C3bi-ms). C3bi- ms, probably because of their smaller size, bound to a higher proportion of cells than did EC3bi. C3bi-ms bound to greater than 90 percent of mature neutrophils, 85 percent of monocytes, 92 percent of erythrocytes, and 12 percent of peripheral blood lymphocytes. Binding of C3bi-ms to neutrophils, monocytes, and erythrocytes was inhibited by fluid-phase C3bi, Fab anti-C3c, or Fab anti-C3d but was not inhibited by F(ab')(2) anti-CR(1) (C3b receptor) or F(ab')(2) anti-CR(2) (C3d receptor) nor by fluid-phase C3b, C3c, or C3d. This indicated that monocytes, neutrophils, and erythrocytes expressed C3bi receptors (CR(3)) that were separate and distinct from CR(1) and CR(2) and specific for a site in the C3 molecule that was only exposed subsequently to cleavage of C3b by C3b inactivator and that was either destroyed, covered, or liberated by cleavage of C3bi into C3c and C3d fragments. Lymphocytes differed from these other cell types in that they expressed CR2 in addition to CRa. Lymphocyte C3bi-ms rosettes were inhibited from 50 to 84 percent by F(ab')(2)-anti-CR(2) or fluid-phase C3d, whereas C3d-ms rosettes were inhibited completely by F(ab')(2) anti-CR(2), fluid-phase C3bi, or fluid- phase C3d. Thus, with lymphocytes, C3bi was bound to CR(3), and in addition was bound to CR(2) by way of the intact d region of the C3bi molecule. In studies of the acquisition of C receptors occurring during myeloid cell maturation, the ability to rosette with C3bi-coated particles was detected readily with immature low-density cells, whereas this ability was nearly undetectable with high density mature polymorphonuclear cells. This absence of C3bi binding to polymorphs was not due to a loss of the CR(3) but instead was due to the maturation-linked acquisition of the abiity to secrete elastase that cleaved reagent particle-bound C3bi into CR(3)-unreactive C3d. Neither neutrophils nor monocytes bound C3d-coated particles at any stage of maturation. Assay of CR(3) with mature neutrophils required inhibition of neutrophil elastase with either soybean trypsin inhibitor or anti-elastase antibodies, and the amounts of these elastase inhibitors required to allow EC3bi rosette formation increased with neutrophil maturation. Because lymphocytes bound C3bi to CR(2) as well as to CR(3), specific assay of lymphocyte CR(3) required saturation of membrane CR(2) with Fab' anti-CR(2) before assay for rosettes with C3bi-ms. Only 3.5 percent of anti-CR(2)- treated peripheral blood lymphocytes bound C3bi-ms. Therefore, among normal blood lymphocytes the majority of the 12 percent C3bi-ms-binding cells expressed only CR(2) (8.5 percent), and the small proportion of C3bi-ms- binding cells that expressed CR(3) (3.5 percent) represented a distinct subset from the CR2(+) cells. Double-label assay indicated that 3.0 percent out of 3.5 percent of these CR(3)-bearing lymphocytes were B cells because they expressed membrane immunoglobulins. Of the remaining CR(3)(+) cells, 0.2 percent expressed either Leu-1 or 3A1 T cell antigens, and 0.6 percent expressed the OKM-1 monocyte-null lymphocyte determinant.

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Methods for Obtaining Purified Lymphocytes, Glass-adherent Mononuclear Cells, and a Population Containing Both Cell Types From Human Peripheral Blood

Blood ◽

10.1182/blood.v40.1.77.77 ◽

1972 ◽

Vol 40 (1) ◽

pp. 77-89 ◽

Cited By ~ 29

Author(s):

William R. Levis ◽

Jay H. Robbins

Keyword(s):

Peripheral Blood ◽

Mononuclear Cells ◽

Human Peripheral Blood ◽

Human Leukocyte ◽

Culture Fluid ◽

Cell Types ◽

Peripheral Blood Lymphocytes ◽

Limiting Factor ◽

Lymphocyte Populations ◽

Two Populations

Abstract Methods are presented for obtaining simultaneously or separately two populations of cells from human peripheral blood, lymphocytes and monocytes, both of which are required to obtain blastogenesis and DNA synthesis in human leukocyte cultures. A simple 5-min centrifugation of heparinized blood yields a mononuclear leukocyte culture fluid containing 70-90% lymphocytes with few granulocytes but with sufficient numbers of monocytes so that the latter cell is not a limiting factor in the blastogenic reaction. A method is also presented for removing both granulocytes and monocytes from lymphocyte populations in a manner that permits monitoring and choice of the degree of lymphocyte purification. A method is also presented for obtaining glass-adherent mononuclear cells that do not undergo blastogenesis but will enable suitably stimulated "purified" lymphocytes to undergo blastogenesis. Studies of the function and morphology of these different cell populations are presented.

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Comprehensive multi-omics single-cell data integration reveals greater heterogeneity in the human immune system

10.1101/2021.07.25.453651 ◽

2021 ◽

Author(s):

Congmin Xu ◽

Junkai Yang ◽

Astrid Kosters ◽

Benjamin R Babcock ◽

Peng Qiu ◽

...

Keyword(s):

Immune System ◽

Single Cell ◽

Immune Cell ◽

Cell Types ◽

Cell Receptor ◽

Surface Proteins ◽

Cell Type ◽

Human Immune System ◽

Receptor Repertoire ◽

Human Immune

Single-cell transcriptomics enables the definition of diverse human immune cell types across multiple tissue and disease contexts. Still, deeper biological understanding requires comprehensive integration of multiple single-cell omics (transcriptomic, proteomic, and cell receptor repertoire). To improve the identification of diverse cell types and the accuracy of cell-type classification in our multi-omics single-cell datasets, we developed SuPERR-seq, a novel analysis workflow to increase the resolution and accuracy of clustering and allow for the discovery and characterization of previously hidden cell subsets. We show that by incorporating information from cell-surface proteins and immunoglobulin transcript counts, we accurately remove cell doublets and prevent widespread cell-type misclassification. This approach uniquely improves the identification of heterogeneous cell types in the human immune system, including a novel subset of antibody-secreting cells in the bone marrow.

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Glycosphingolipid Domains on Cell Plasma Membrane

Bioscience Reports ◽

10.1023/a:1020277820120 ◽

1999 ◽

Vol 19 (3) ◽

pp. 197-208 ◽

Cited By ~ 10

Author(s):

Maurizio Sorice ◽

Tina Garofalo ◽

Roberta Misasi ◽

Vincenza Dolo ◽

Giuseppe Lucania ◽

...

Keyword(s):

Plasma Membrane ◽

Cell Surface ◽

Cell Activation ◽

Human Peripheral Blood ◽

Neuroblastoma Cells ◽

Cell Types ◽

Peripheral Blood Lymphocytes ◽

Lymphoid Cells ◽

Signaling Complex ◽

3T3 Fibroblasts

In this study we analyzed by immunofluorescence, laser confocal microscopy, immunoelectron microscopy and label fracture technique the ganglioside distribution on the plasma membrane of several different cell types: human peripheral blood lymphocytes (PBL), Molt-4 lymphoid cells, and NIH 3T3 fibroblasts, which mainly express monosialoganglioside GM3, and murine NS20Y neuroblastoma cells, which have been shown to express a high amount of monosialoganglioside GM2. Our observations showed an uneven distribution of both GM3 and GM2 on the plasma membrane of all cells, confirming the existence of ganglioside-enriched microdomains on the cell surface. Interestingly, in lymphoid cells the clustered immunolabeling appeared localized over both the microvillous and the nonvillous portions of the membrane. Similarly, in cells growing in monolayer, the clusters were distributed on both central and peripheral regions of the cell surface. Therefore, glycosphingolipid clusters do not appear confined to specific areas of the plasma membrane, implying general functions of these domains, which, as structural components of a cell membrane multimolecular signaling complex, may be involved in cell activation and adhesion, signal transduction and, when associated to caveolae, in endocytosis of specific molecules.

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Oral Selective TLR8 Agonist Selgantolimod Induces Multiple Immune Cell Responses in Humans

Viruses ◽

10.3390/v13122400 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2400

Author(s):

Natarajan Ayithan ◽

Alip Ghosh ◽

Ankit Dwivedi ◽

Jeffrey J. Wallin ◽

Susanna K. Tan ◽

...

Keyword(s):

Peripheral Blood ◽

Cellular Response ◽

Cell Activation ◽

Immune Cell ◽

Nk Cell ◽

Human Study ◽

Myeloid Cell ◽

Lymphoid Cells ◽

Cell Responses ◽

Multiple Immune Cell

TLR8 agonists have the potential for use as immunomodulatory components in therapeutic modalities for viral infections such as chronic HBV (CHB) and HIV. In this study, using peripheral blood samples from a phase 1a clinical trial, we examined the acute effects of a single oral administration of a selective TLR8 agonist on immune cell phenotypes. Administration of the TLR8 agonist selgantolimod (SLGN) in healthy individuals resulted in alteration in frequencies of peripheral blood monocytes, pDCs, mDCs and MAIT cells. Frequencies of mDCs and lymphoid cells significantly reduced after 8 h of SLGN administration, whereas pDC frequencies significantly increased, with changes possibly reflecting migration of different cell types between peripheral and tissue compartments in response to the agonist. Myeloid cell activation was evident by an upregulated expression of co-stimulatory molecules CD40 and CD86 accompanied by the production of IL-6 and IL-18 from these cells. Concomitantly, there was induction of the early activation marker CD69 on innate and adaptive lymphoid cells, including MAIT and NK cell subsets. Further, these activated lymphoid cells had enhanced expression of the effector molecules granzyme B and perforin. Microarray analysis of isolated lymphocytes and monocytes from baseline and post-SLGN treatment revealed changes in expression of genes involved in cellular response to cytokine stimulus, innate immune response, myeloid cell differentiation and antigen receptor-mediated signaling pathway. In a preliminary analysis of samples from CHB patients treated with selgantolimod, activation of innate and adaptive lymphocytes was evident. In conclusion, this first in-human study shows that selgantolimod administration in humans results in activation of multiple immune cell responses with antiviral potential.

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Single cell profiling of capillary blood enables out of clinic human immunity studies

Scientific Reports ◽

10.1038/s41598-020-77073-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Tatyana Dobreva ◽

David Brown ◽

Jong Hwee Park ◽

Matt Thomson

Keyword(s):

Gene Expression ◽

Immune System ◽

Single Cell ◽

Immune Cell ◽

Cost Effective ◽

Cell Types ◽

Individual Variability ◽

Capillary Blood ◽

Specific Gene ◽

Human Immune System

AbstractAn individual’s immune system is driven by both genetic and environmental factors that vary over time. To better understand the temporal and inter-individual variability of gene expression within distinct immune cell types, we developed a platform that leverages multiplexed single-cell sequencing and out-of-clinic capillary blood extraction to enable simplified, cost-effective profiling of the human immune system across people and time at single-cell resolution. Using the platform, we detect widespread differences in cell type-specific gene expression between subjects that are stable over multiple days.

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Direct inhibition of CDK9 blocks HIV-1 replication without preventing T-cell activation in primary human peripheral blood lymphocytes

Gene ◽

10.1016/j.gene.2007.09.010 ◽

2007 ◽

Vol 405 (1-2) ◽

pp. 65-78 ◽

Cited By ~ 40

Author(s):

Dominic Salerno ◽

Muneer G. Hasham ◽

Renée Marshall ◽

Judit Garriga ◽

Alexander Y. Tsygankov ◽

...

Keyword(s):

T Cell ◽

T Cell Activation ◽

Peripheral Blood ◽

Cell Activation ◽

Human Peripheral Blood ◽

Peripheral Blood Lymphocytes ◽

Direct Inhibition ◽

Blood Lymphocytes ◽

Human Peripheral Blood Lymphocytes ◽

Hiv 1

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Effects of sex and aging on the immune cell landscape as assessed by single-cell transcriptomic analysis

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2023216118 ◽

2021 ◽

Vol 118 (33) ◽

pp. e2023216118

Author(s):

Zhaohao Huang ◽

Binyao Chen ◽

Xiuxing Liu ◽

He Li ◽

Lihui Xie ◽

...

Keyword(s):

Immune System ◽

Nk Cells ◽

Cell Activation ◽

Plasma Cells ◽

Immune Cell ◽

Cell Communication ◽

Lower Percentage ◽

Human Immune System ◽

Communication Analysis ◽

The Impact

Sex and aging influence the human immune system, resulting in disparate responses to infection, autoimmunity, and cancer. However, the impact of sex and aging on the immune system is not yet fully elucidated. Using small conditional RNA sequencing, we found that females had a lower percentage of natural killer (NK) cells and a higher percentage of plasma cells in peripheral blood compared with males. Bioinformatics revealed that young females exhibited an overrepresentation of pathways that relate to T and B cell activation. Moreover, cell–cell communication analysis revealed evidence of increased activity of the BAFF/APRIL systems in females. Notably, aging increased the percentage of monocytes and reduced the percentage of naïve T cells in the blood and the number of differentially expressed genes between the sexes. Aged males expressed higher levels of inflammatory genes. Collectively, the results suggest that females have more plasma cells in the circulation and a stronger BAFF/APRIL system, which is consistent with a stronger adaptive immune response. In contrast, males have a higher percentage of NK cells in blood and a higher expression of certain proinflammatory genes. Overall, this work expands our knowledge of sex differences in the immune system in humans.

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