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Shen-Orr, S.

Publications and source records attributed to Shen-Orr, S..

6 recordsLinked to original sources

Aging restricts maturation of CXCL13+ T follicular helper cells in human immunity

A decline in specific antibody responses is a hallmark of human aging, yet the differential contributions of B and T lymphocytes and their interactions remain unclear. CXCL13 is a critical chemokine that shapes germinal center organization, but the regulation of human-specific CXCL13+ Tfh cells during aging is not known. Using human tonsil organoids, single-cell RNA sequencing, and CRISPR perturbations, we mapped age-associated changes in T follicular helper (Tfh) cells, the cell type that provides T cell "help" to B cells in germinal centers (GCs). Tonsil organoids from older donors generated weaker influenza-specific antibody responses, which we traced to Tfh cell defects rather than B cells. Single-cell profiling revealed a selective loss of mature CXCL13 GC-Tfh cells accompanied by accumulation of Tfh precursor states. Trajectory analysis showed that aging arrests Tfh cell maturation at the early activated precursor transition, and CRISPR perturbations identified BACH2 and SOX4 as transcriptional regulators of differentiation reduced with age. These findings reveal a human-specific mechanism of immune aging with implications for strategies to restore humoral immunity.

immunology↗

Cytokine Regulation of Human Antibody Responses to Influenza Vaccines

Studies show that human vaccine responses widely vary. Here, we analyzed data measuring 66 cytokines from 4 different inactivated influenza vaccine (IIV) cohorts over 5 seasons (N=581) and identified a significant correlation between baseline/day 0 serum IL-18 and IFN-{beta} concentrations and the vaccine-specific antibody response on day 28, suggesting these factors may have an adjuvant-like effect. To investigate this further, we tested the impact of 19 cytokines on the development of anti-influenza antibody response when administered together with the IIV vaccine in human tonsil and spleen organoids. We found that Type I IFNs (IFN-{beta} and others), IL-21, IL-12, IL-10, but not IL-18 or IFN-{gamma}, enhanced the antibody response. The live attenuated influenza vaccine (LAIV) induced a stronger antibody response than the inactivated one in organoids. Adding a single cytokine, IFN-{beta}, to IIV stimulation recapitulated most of the live vaccine-specific cytokine activation program. It increased the antibody response of the inactivated vaccine to that of the LAIV. Two other antibody-boosting cytokines, IL-12 and IL-21, were induced by LAIV but not by Type I IFNs, indicating different cytokines can affect different pathways leading to a robust antibody response. We then generated cytokine mRNA lipid nanoparticles (LNPs) to test the effect of cytokines on IIV response in a mouse model of immunization. We found that IL-21-LNPs augmented the quantity and breadth of the antibody responses, while IFN-{beta} LNPs enhanced durability. These findings identified parallel cytokine pathways regulating human vaccine responses and provide a rationale for using cytokines as adjuvants to mimic the effectiveness of live-attenuated vaccines without the risk of viral replication.

immunology↗

Systematic mapping of neural signals in the periphery reveals a rich and specific alphabet for immune cell communication

Accumulating evidence indicate a strong link between neural signals and the immune system. Given neural signals constitute a large family that may be leveraged for communication, we systematically explored the neuro-immune regulation network in the periphery and uncovered a broad yet lineage selective expression of neuro-receptors on immune cells. We constructed a rich social immune network map showing the neural molecular pathways supporting the regulation of the immune system at steady state. Our results emphasize neuro-receptors role in the commitment and differentiation of B and T cells along their developmental process. We identified the immune cells functionality in the specific tissue is extensively shaped by the communication with the microenvironment and nervous systems via a rich alphabet of neural mediators. Collectively, our findings suggest neural genes are an integral part of the immune regulatory system and provide clear testable new avenues of experimental follow up for neuroimmunologists and immunologists alike. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=185 SRC="FIGDIR/small/522179v1_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@d4032eorg.highwire.dtl.DTLVardef@11ce763org.highwire.dtl.DTLVardef@9b279eorg.highwire.dtl.DTLVardef@45fc89_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LI160 neural genes potentially active in immune cells in the periphery with high specificity to lineage C_LIO_LINeuro-receptors co-expressed in immune lineages are enriched for biological functions C_LIO_LIChanges in neuro-receptors expression influence the HCS differentiation and commitment C_LIO_LIImmune-microenvironment neural signaling architecture reflects tissue biological role C_LI

immunology↗

An Inflammatory Clock Predicts Multi-morbidity, Immunosenescence and Cardiovascular Aging in Humans

While many diseases of aging have been linked to the immunological system, immune metrics with which to identify the most at-risk individuals are lacking. Here, we studied the blood immunome of 1001 individuals age 8-96 and derived an inflammatory clock of aging (iAge), which tracked with multi-morbidity and immunosenescence. In centenarians, iAge was on average, 40 years lower than their corresponding chronological age. The strongest contributor to this metric was the chemokine CXCL9, which was involved in cardiac aging, affected vascular function, and down-regulated Sirtuin-3, a longevity-associated molecule. Thus, our results identify an important link between inflammatory molecules and pathways known to govern lifespan.

immunology↗

High Resolution Comparison of Cancer-Related Developmental Processes Using Trajectory Alignment

Abnormal differentiation is a key feature of cancer, yet currently there is no framework that enables a comparative analysis of differentiation processes across patients while preserving their individual-level resolution. Here, we present devMap, an algorithm that uses high-dimensional trajectory alignment to anchor cancer-related developmental processes to a common backbone process, thus allowing for their systematic comparison. We applied devMap to bone marrow samples from healthy individuals and AML patients profiled by single-cell mass-cytometry at cancer diagnosis and following treatment. devMap standardization enabled us to infer the developmental status of the AML samples and characterize its evolution following treatment and in relapse. Application of devMap on an external dataset of AML bone marrow samples revealed conserved patterns of developmental signaling responses in AML that were obscured by traditional methodologies for developmental inference.

systems biology↗

CD38 is a key regulator of enhanced NK cell immune responses during pregnancy through its role in immune synapse formation

Natural killer (NK) cells use a diverse array of activating and inhibitory surface receptors to detect threats and provide an early line of defense against viral infections and cancer. Here, we demonstrate that the cell surface protein CD38 is a key human NK cell functional receptor through a role in immune synapse formation. CD38 expression marks a mature subset of human NK cells with a high functional capacity. NK cells expressing high levels of CD38 display enhanced killing and IFN-{gamma} secretion in response to influenza virus-infected and tumor cells. Inhibition of CD38 enzymatic activity does not influence NK cell function, but blockade of CD38 and its ligand CD31 abrogates killing and IFN-{gamma} expression in response to influenza-infected cells. Blockade of CD38 on NK cells similarly inhibits killing of tumor cells. CD38 localizes and accumulates at the immune synapse between NK cells and their targets, and blocking CD38 severely abrogates the ability of NK cells to form conjugates and immune synapses with target cells. Thus, CD38 plays a critical role in NK cell immune synapse formation. These findings open new avenues in immunotherapeutic development for cancer and infection by revealing a critical role for CD38 in NK cell function.

immunology↗