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Colucci, F.

Publications and source records attributed to Colucci, F..

6 recordsLinked to original sources

Single-cell profiling of human bone marrow reveals multiple myeloma progression is accompanied by an increase in CD56bright bone marrow resident NK cells.

Natural killer (NK) cells play a key role in the innate immune response against tumour progression. While the immune microenvironment in multiple myeloma (MM) becomes increasingly dysfunctional during disease evolution, little is known about changes in the NK cell compartment. Using primary samples from clinical trial patients, we performed detailed phenotypic analyses of bone marrow mononuclear cells from MGUS, SMM, and newly diagnosed MM patients. We found that disease progression is associated with an increase in CD56bright NK cells with a dynamic positive association between this NK cell subset and local tumour burden. We generated a large single-cell RNA sequencing dataset of >100,000 NK cells from healthy donor individuals and plasma cell disorder patients and identify a bone marrow specific CD56bright-like NK cell population (BM-NK) that is enriched in the marrow of MM patients. These findings highlight the evolution of the NK-cell compartment in MM and suggest a role for BM-resident CD56bright NK cells with impaired cytotoxicity in promoting immune evasion.

cancer biology↗

Kir6.1, a component of an ATP-sensitive potassium channel, regulates natural killer cell development

AO_SCPLOWBSTRACTC_SCPLOWInvolved in immunity and reproduction, natural killer (NK) cells offer opportunities to develop new immunotherapies to treat infections and cancer or to alleviate pregnancy complications. Most current strategies use cytokines or antibodies to enhance NK-cell function, but none use ion channel modulators, which are widely used in clinical practice to treat hypertension, diabetes, epilepsy, and other conditions. Little is known about ion channels in NK cells. We show that Kcnj8, which codes for the Kir6.1 subunit of a certain type of ATP-sensitive potassium (KATP) channel, is highly expressed in murine splenic and uterine NK cells compared to other K+ channels previously identified in NK cells. Kcnj8 expression is highest in the most mature subset of splenic NK cells (CD27-CD11b+) and in NKG2A+ or Ly49C/I+ educated uterine NK cells. Using patch clamping, we show that a subset of NK cells expresses a current sensitive to the Kir6.1 blocker PNU-37883A. Kcnj8 does not participate in NK cell degranulation in response to tumor cells in vitro or rejection of tumor cells in vivo. Transcriptomics show that genes previously implicated in NK cell development are amongst those differentially expressed in CD27-CD11b+ NK cells deficient of Kcnj8. Indeed, we found that mice with NK-cell specific Kcnj8 gene ablation have fewer CD11b+CD27- and KLRG-1+ NK cells in the bone barrow and spleen. These results show that the KATP subunit Kir6.1 has a key role in NK-cell development.

immunology↗

Single-Cell Analysis Identifies Thymic Maturation Delay in Growth-Restricted Neonatal Mice

Fetal growth restriction (FGR) causes a wide variety of defects in the neonate which can lead to increased risk of heart disease, diabetes, anxiety and other disorders later in life. However, the effect of FGR on the immune system, is poorly understood. We used a well-characterized mouse model of FGR in which placental Igf-2 production is lost due to deletion of the placental specific Igf-2 P0 promotor. The thymi in such animals were reduced in mass with a [~]70% reduction in cellularity. We used single cell RNA sequencing (Drop-Seq) to analyze 7264 thymus cells collected at postnatal day 6.\n\nWe identified considerable heterogeneity among the Cd8/Cd4 double positive cells with one subcluster showing marked upregulation of transcripts encoding a sub-set of proteins that contribute to the surface of the ribosome. The cells from the FGR animals were underrepresented in this cluster. Furthermore, the distribution of cells from the FGR animals was skewed with a higher proportion of immature double negative cells and fewer mature T-cells. Cell cycle regulator transcripts also varied across clusters. The T-cell deficit in FGR mice persisted into adulthood, even when body and organ weights approached normal levels due to catch-up growth. This finding complements the altered immunity found in growth restricted human infants. This reduction in T-cellularity may have implications for adult immunity, adding to the list of adult conditions in which the in utero environment is a contributory factor.

developmental biology↗

Maternal group 2 innate lymphoid cells control fetal growth and protect from endotoxin-induced abortion in mice

Group 2 innate lymphoid cells (ILC2s) adapt to tissue physiology and contribute to immunity, inflammatory pathology and metabolism. We show that mouse uterine ILC2s have a heightened type-2 gene signature and expand during pregnancy. Indeed, maternal ILC2s promote fetal growth and protect against fetal mortality upon systemic endotoxin challenge. Absence of ILC2s leads to utero-placental abnormalities, including poor vascular remodelling, increased Il1b and decreased Il4, Il5, and Il13 gene expression, and reduced alternative activation of dendritic cells (DCs) and macrophages. Placentas exhibit signs of adaptation to stress, including larger maternal blood spaces and increased expression of nutrient transporter genes. Endotoxin induces the expansion of IL-1{beta}-producing uterine DCs and, in response, more uterine ILC2s produce IL-4, IL-5 and IL-13. In a protective feedback mechanism, these cytokines suppress IL-1{beta}-producing DCs, in line with a protective role of uILC2s against endotoxin-induced abortion. Uterine ILC2s emerge as pivotal for both normal and complicated pregnancies.

immunology↗

High-resolution genetic and phenotypic analysis of KIR2DL1 alleles and their association with pre-eclampsia

Killer-cell immunoglobulin-like receptor (KIR) genes are inherited as haplotypes, expressed by NK cells and linked to outcomes of infectious diseases and pregnancy. Understanding how genotype relates to phenotype is difficult because of the extensive diversity of the KIR family. Indeed, high-resolution KIR genotyping and phenotyping in single NK cells in the context of disease association is lacking. Here, we describe a new method to separate NK cells expressing allotypes of the KIR2DL1 gene carried by the KIR A haplotype (KIR2DL1A) from those expressing KIR2DL1 alleles carried by the KIR B haplotype (KIR2DL1B). We find that in KIR AB heterozygous individuals, different KIR2DL1 allotypes can be detected both in peripheral blood and in uterine single NK cells. Using this new method, we demonstrate that both blood and uterine NK cells co-dominantly express KIR2DL1A and KIR2DL1B allotypes, but with a predominance of KIR2DL1A variants, which associate with enhanced NK cell function. In a case-control study of pre-eclampsia, we show that KIR2DL1A, not KIR2DL1B, associates with increased disease risk. This method will facilitate our understanding of how individual KIR2DL1 allelic variants affect NK cell function and contribute to disease risk.

immunology↗

Molecular definition of group 1 innate lymphoid cells in the mouse uterus

Determining the function of uterine lymphocytes is challenging because of the rapidly changing nature of the organ in response to sex hormones and, during pregnancy, to the invading fetal trophoblast cells. Here we provide the first genome-wide transcriptome atlas of mouse uterine group 1 innate lymphoid cells (g1 ILCs) at mid-gestation. The composition of g1 ILCs fluctuates throughout reproductive life, with Eomes-veCD49a+ ILC1s dominating before puberty and specifically expanding in second pregnancies, when the expression of CXCR6, a marker of memory cells, is upregulated. Tissue-resident Eomes+CD49a+ NK cells (trNK), which resemble human uterine NK cells, are most abundant during early pregnancy, and showcase gene signatures of responsiveness to TGF-{beta}, connections with trophoblast, epithelial, endothelial and smooth muscle cells, leucocytes, as well as extracellular matrix. Unexpectedly, trNK cells express genes involved in anaerobic glycolysis, lipid metabolism, iron transport, protein ubiquitination, and recognition of microbial molecular patterns. Conventional NK cells expand late in gestation and may engage in crosstalk with trNK cells involving IL-18 and IFN-{gamma}. These results identify trNK cells as the cellular hub of uterine g1 ILCs at mid-gestation and mark CXCR6+ ILC1s as potential memory cells of pregnancy.

immunology↗