Biology subjects

Rautela, J.

Publications and source records attributed to Rautela, J..

6 recordsLinked to original sources

bioRxiv2023

CD45 limits Natural Killer cell development from common lymphoid progenitors

The clinical development of Natural Killer (NK) cell-mediated immunotherapy marks a milestone in the development of new cancer therapies and has gained traction due to the intrinsic ability of the NK cell to target and kill tumour cells. To fully harness the tumour killing ability of NK cells, we need to improve NK cell persistence and overcome suppression of NK cell activation in the tumour microenvironment. The trans-membrane, protein tyrosine phosphatase CD45, regulates NK cell homeostasis, with genetic loss of CD45 in mice resulting in increased numbers of mature NK cells [1-3]. This suggests that CD45-deficient NK cells might display enhanced persistence following adoptive transfer. However, here we demonstrated that adoptive transfer of CD45-deficiency did not enhance NK cell persistence in mice, and instead, the homeostatic disturbance of NK cells in CD45-deficient mice stemmed from a developmental defect in the common lymphoid progenitor population. The enhanced maturation within the CD45-deficient NK cell compartment was intrinsic to the NK cell lineage, and independent of the developmental defect. CD45 is not a conventional immune checkpoint candidate, as systemic loss is detrimental to T and B cell development [4-6], compromising the adaptive immune system. Nonetheless, this study suggests that inhibition of CD45 in progenitor or stem cell populations may improve the yield of in vitro generated NK cells for adoptive therapy.

cell biology↗

bioRxiv2022

CIS calibrates GM-CSF signalling strength to regulate macrophage polarization via a STAT5-IRF8 axis

The cytokine granulocyte-macrophage-colony stimulating factor (GM-CSF) possesses the ability to differentiate macrophages (MOs) with opposing functions, namely proinflammatory M1-like and immunosuppressive M2-like. Despite the importance and opposing functional outcomes of these processes, the intrinsic mechanism that regulates the functional polarization of MOs under GM-CSF signaling remains elusive. Here we show that GM-CSF induced MOs polarisation resulted in the expression of the Cytokine-inducible SH2-containing protein (CIS), and that CIS deficiency diverted differentiation of monocytes into immunosuppressive M2-like MOs expression. CIS deficiency resulted in the hyperactivation of the JAK-STAT5 signaling pathway, consequently promoting the downregulation of the transcription factor Interferon Regulatory Factor 8 (IRF8). Loss and gain of function approaches highlighted IRF8 as a critical instructor of the M1-like polarisation program. In vivo, CIS deficiency led to skewing to M2-like macrophages, which induced strong Th2 immune responses characterised by the development of severe experimental asthma. Collectively, we reveal a CIS-censored mechanism interpreting the opposing actions of GM-CSF in MO differentiation and uncovering its role in controlling allergic inflammation.

immunology↗

bioRxiv2021

Glycan engineering using synthetic ManNAc analogues enhances sialyl-Lewis-X expression and adhesion of leukocytes

Sialyl-Lewis-X (sLeX/CD15s) epitopes regulate cell adhesion via interactions with selectins. High levels of sLeX are associated with chronic inflammation. Intense efforts have been devoted for the development of sLeX mimetics for the prevention of atherosclerosis. By contrast, low levels of sLeX are associated with leukocyte adhesion deficiency (LAD) disorders. In this context, we employed metabolic glycan engineering to alter the fine structures of sialoglycans. Treatment of HL-60 (human acute myeloid leukemia) cells with peracetyl N-cyclobutanoyl-D-mannosamine (Ac4ManNCb) resulted in a four-fold increase in both sLeX levels and adhesion to E-selectin-Fc chimera. Enhanced sLeX levels on CD162/PSGL-1, CD43, and CD44 were observed through immunoprecipitation. Molecular dynamics (MD) simulations on interactions with E-selectin revealed dramatic differentials in the conformational dynamics of sLeX-Cb compared to sLeX, highlighting the significance of remote N-acyl side chains of sialic acids in facilitating bio-active conformations. These results provide opportunities for pharmacological interventions in both LAD and chronic inflammation. Table of Contents O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=83 SRC="FIGDIR/small/473788v2_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@172ab54org.highwire.dtl.DTLVardef@14e45acorg.highwire.dtl.DTLVardef@1c05c65org.highwire.dtl.DTLVardef@1f2056e_HPS_FORMAT_FIGEXP M_FIG C_FIG Remote substituents on the tetrasaccharide sialyl-Lewis X (sLeX / CD15s) influence ensembles of bio-active conformations and alter biological outcomes. Treatment with peracetyl N-cyclobutanoyl-D-mannosamine (Ac4ManNCb) results in four-fold enhancement in the expression of sialyl-Lewis-X (sLeX / CD15s) and adhesion to E-selectin (CD62E). Molecular dynamics simulations show that the sLeX-Cb prefers a flatter bio-active conformation (gray) compared to wild-type sLeX (cyan). Institute and/or researcher Twitter usernames: @NImmunology @Gops_GlycoIndia

biochemistry↗

bioRxiv2020

The clonal and molecular aetiology of emergency dendritic cell development

Extrinsic regulation of single haematopoietic stem and progenitor cell (HSPC) fate is crucial for immune cell development. Here, we examine the aetiology of Flt3 ligand (Flt3L)-mediated emergency development of type 1 conventional dendritic cells (cDC1s), which results in enhanced immunity against infections and cancer. Using cellular barcoding, we demonstrate a predominant role of enhanced clonal expansion and moderate contribution via recruitment of additional cDC1-generating HSPCs. The selective cDC1 expansion occurs primarily via multi-/oligo-potent clones, without compromising output to other lineages. To understand the molecular hallmarks early during a Flt3L response, we develop Divi-Seq to simultaneously profile cell division history, surface phenotype and transcriptional state of single HSPCs. We discover that Flt3L-responsive HSPCs maintain a proliferative early progenitor-like state, which leads to selective emergence of CD11c+cKit+ transitional precursors with high cellular output to cDC1s. These findings inform the mechanistic action of Flt3L in natural immunity and immunotherapy at a clonal level.

immunology↗

bioRxiv2018

Therapeutic blockade of Activin-A improves NK cell function and anti-tumor immunity

Natural killer (NK) cells are innate lymphocytes that play a major role in immunosurveillance against tumor initiation and metastasis spread. Signals and checkpoints that regulate NK cell fitness and function in the tumor microenvironment are not well defined. Transforming grow factor (TGF)-{beta} is a recognized suppressor of NK cells that inhibits IL-15 dependent signaling events and induces cellular transdifferentiation, however the role of other SMAD signaling pathways in NK cells is unknown. In this report, we show that NK cells express the type I Activin receptor, ALK4, which upon binding its ligand Activin-A, phosphorylates SMAD2/3 to efficiently suppress IL-15-mediated NK cell metabolism. Activin-A impairs human and mouse NK cell proliferation and downregulates intracellular granzyme B levels to impair tumor killing. Similar to TGF-{beta}, Activin-A also induced SMAD2/3 phosphorylation and drove NK cells to upregulate several ILC1-like surface markers including CD69, TRAIL and CD49a. Activin-A also induced these changes on TGF-{beta} receptor deficient NK cells, highlighting that Activin-A and TGF-{beta} are independent pathways that drive SMAD2/3-mediated NK cell suppression. Finally, therapeutic inhibition of Activin-A by Follistatin significantly slowed orthotopic melanoma growth in mice. These data highlight independent SMAD2/3 pathways target NK cell fitness and function and identify a novel therapeutic axis to promote tumor immunity.\n\nOne Sentence Summary: Activin-A can directly inhibit NK cell effector functions, promote NK cells transdifferentiation into ILC1-like cells and suppress anti-melanoma immunity.

immunology↗

bioRxiv2018

Efficient genome editing of human natural killer cells by CRISPR RNP

The ability to genetically modify CD8 T cells using viral gene delivery has facilitated the development of next generation of cancer immunotherapies such as chimeric antigen receptor (CAR) T cells engineered to specifically kill tumor cells. Development of immunotherapies targeting natural killer (NK) cells have stalled in part by their resistance to viral gene delivery. Here, we describe an efficient approach to genetically edit human NK cells by electroporation and CRISPR-Cas9 ribonucleoprotein (RNP) complexes. We detail electroporation pulse codes and buffer optimization for protein uptake by human NK cells and viability, and the efficiency of this approach over other methods. To highlight the transformative step this technique will have for NK cell immunotherapy drug discovery, we deleted NKp46 and CIS in primary human NK cells and validated murine findings on their key roles in regulating NK cell anti-tumor function.

immunology↗