Conventional type 1 dendritic cells (cDC1s) are superior in antigen cross-presentation and priming CD8 T cell anti-tumor immunity and thus, are a target of high interest for cancer immunotherapy. Type I interferon (IFN) is a potent inducer of antigen cross-presentation, but, unfortunately, shows only modest results in the clinic given the short half-life and high toxicity of current type I IFN therapies, which limit IFN exposure in the tumor. CD8 T cell immunity is dependent on IFN signaling in cDC1s and preclinical studies suggest targeting IFN directly to cDC1s may be sufficient to drive anti-tumor immunity.
View Article and Find Full Text PDFRecombinant adeno-associated virus (AAV) is an effective platform for therapeutic gene transfer; however, tissue-tropism differences between species are a challenge for successful translation of preclinical results to humans. We evaluated the use of primary hepatocyte cultures to predict liver-directed AAV expression in different species. We assessed whether AAV transduction assays in cultured primary hepatocytes from mice, nonhuman primates (NHPs), and humans could model liver-directed AAV expression of valoctocogene roxaparvovec (AAV5-hFVIII-SQ), an experimental gene therapy for hemophilia A with a hepatocyte-selective promoter.
View Article and Find Full Text PDFAdeno associated virus (AAV) capsids are a leading modality for in vivo gene delivery. Complete and precise characterization of capsid particles, including capsid and vector genome concentration, is necessary to safely and efficaciously dose patients. Size exclusion chromatography (SEC) coupled to multiangle light scattering (MALS) offers a straightforward approach to comprehensively characterize AAV capsids.
View Article and Find Full Text PDFCathepsin H is a member of the papain superfamily of lysosomal cysteine proteases. It is the only known aminopeptidase in the family and is reported to be involved in cancer and other major diseases. Like many other proteases, it is synthesized as an inactive proenzyme.
View Article and Find Full Text PDFClathrin-mediated endocytosis (CME) is facilitated by a precisely regulated burst of actin assembly. PtdIns(4,5)P2 is an important signaling lipid with conserved roles in CME and actin assembly regulation. Rhomboid family multipass transmembrane proteins regulate diverse cellular processes; however, rhomboid-mediated CME regulation has not been described.
View Article and Find Full Text PDFPodosomes are dynamic actin-based structures that mediate adhesion to the extracellular matrix and localize matrix degradation to facilitate cell motility and invasion. Drebrin-like protein (DBNL), which is homologous to yeast mAbp1 and is therefore known as mammalian actin-binding protein 1 (mAbp1), has been implicated in receptor-mediated endocytosis, vesicle recycling and dorsal ruffle formation. However, it is not known whether mAbp1 regulates podosome formation or cell invasion.
View Article and Find Full Text PDFInvasive cell migration is critical for leukocyte trafficking into tissues. Podosomes are matrix-degrading adhesive structures that are formed by macrophages and are necessary for macrophage migration and invasion. Here, we describe methods for imaging and quantifying podosomes in primary human macrophages and in THP-1 cells, a monocyte cell line that can be differentiated to a macrophage-like state.
View Article and Find Full Text PDFThe dynamic turnover of integrin-mediated adhesions is important for cell migration. Paxillin is an adaptor protein that localizes to focal adhesions and has been implicated in cell motility. We previously reported that calpain-mediated proteolysis of talin1 and focal adhesion kinase mediates adhesion disassembly in motile cells.
View Article and Find Full Text PDFGrowth factor stimulation induces the formation of dynamic actin structures known as dorsal ruffles. Mammalian actin-binding protein-1 (mAbp1) is an actin-binding protein that has been implicated in regulating clathrin-mediated endocytosis; however, a role for mAbp1 in regulating the dynamics of growth factor-induced actin-based structures has not been defined. Here we show that mAbp1 localizes to dorsal ruffles and is necessary for platelet-derived growth factor (PDGF)-mediated dorsal ruffle formation.
View Article and Find Full Text PDFFocal adhesion kinase (FAK) is important for breast cancer progression and invasion and is necessary for the dynamic turnover of focal adhesions. However, it has not been determined whether FAK also regulates the dynamics of invasive adhesions formed in cancer cells known as invadopodia. In this study, we report that endogenous FAK functions upstream of cellular Src (c-Src) as a negative regulator of invadopodia formation and dynamics in breast cancer cells.
View Article and Find Full Text PDFWhile the quantification of cell movement within defined biochemical gradients is now possible with microfluidic approaches, translating this capability to biologically relevant three-dimensional microenvironments remains a challenge. We introduce an accessible platform, requiring only standard tools (e.g.
View Article and Find Full Text PDFPodosomes and the immune synapse are integrin-mediated adhesive structures that share a common ring-like morphology. Both podosomes and immune synapses have a central core surrounded by a peripheral ring containing talin, vinculin and paxillin. Recent progress suggests significant parallels between the regulatory mechanisms that contribute to the formation of these adhesive structures.
View Article and Find Full Text PDFInvasive cancer cells form dynamic adhesive structures associated with matrix degradation called invadopodia. Calpain 2 is a calcium-dependent intracellular protease that regulates adhesion turnover and disassembly through the targeting of specific substrates such as talin. Here, we describe a novel function for calpain 2 in the formation of invadopodia and in the invasive abilities of breast cancer cells through the modulation of endogenous c-Src activity.
View Article and Find Full Text PDFIntegrins are cell-surface adhesion receptors that play a central role in regulating cell migration by mediating interactions between the extracellular matrix and the actin cytoskeleton. Substantial progress has been made in understanding the mechanisms by which the formation and breakdown of adhesions are regulated. Here we describe general methods used to study integrin-mediated cell migration.
View Article and Find Full Text PDFMannan-binding lectin-associated serine proteases (MASPs) are secreted as single-chain precursors and processed into two disulfide bond-linked chains. MASP-3 and MASP-1, derived from the same gene, contain identical A chains, but entirely different catalytic domain-containing B chains. In contrast to MASP-1 and MASP-2, the proteinase activity of MASP-3 has not been described previously.
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