Biology subjects

Bindila, L.

Publications and source records attributed to Bindila, L..

4 recordsLinked to original sources

bioRxiv2023

Deep MALDI-MS Spatial Omics guided by Quantum Cascade Laser Mid-infrared Imaging Microscopy

In spatial omics, highly confident molecular identifications are indispensable for the investigation of complex biology and for spatial biomarker discovery. However, current mass spectrometry (MS)-based spatial omics must compromise between data acquisition speed and biochemical profiling depth, thus often leading to only "putative" molecular identifications. Here, we introduce fast quantum cascade laser mid-infrared imaging microscopy to guide MS imaging to confined tissue areas of high interest, e.g., multicellular spheroid cores or kidney glomeruli, for spatial lipidomics profiling at maximized analytical depth utilizing magnetic resonance-MS imaging at >106 resolution or prm-PASEF-MS2 fragmentation imaging. Instigating selective sulfatide accumulation in arylsulfatase A-deficient mice as ground truth concept, we demonstrate that deep QCL-infrared-guided on-tissue spatial omics unequivocally identifies 120 sulfatides. This approach enables identifications of odd-chain sulfatides and studies of structure-ion mobility-relationships that provide chemical rationales for improvements to current ion mobility prediction algorithms. Workflows and data processing tools are provided as community resources.

biochemistry↗

bioRxiv2023

Fatty acid amide hydrolase drives luminal cell differentiation in the adult mammary gland

Mammary gland development occurs primarily in adulthood, undergoing extensive expansion during puberty followed by cycles of functional specialization and regression with every round of pregnancy/lactation/involution. This process is ultimately driven by the coordinated proliferation and differentiation of mammary epithelial cells. However, the endogenous molecular factors regulating these developmental dynamics are still poorly defined. Endocannabinoid signaling is known to determine cell fate-related events during the development of different organs in the central nervous system and the periphery. Here, we report that the endocannabinoid-degrading enzyme fatty acid amide hydrolase (FAAH) plays a pivotal role in adult mammary gland development. Specifically, it is required for luminal lineage specification in the mammary gland, and it promotes hormone-driven secretory differentiation of mammary epithelial cells by controlling the endogenous levels of anandamide and the subsequent activation of cannabinoid CB1 receptors. Together, our findings shed light on the role of the endocannabinoid system in breast development and point to FAAH as a therapeutic target in milk-production deficits.

developmental biology↗

bioRxiv2021

GPR55 in B cells limits atherosclerosis development and regulates plasma cell maturation

Identifying novel pathways regulating the adaptive immune response in chronic inflammatory diseases such as atherosclerosis is of particular interest in view of developing new therapeutic drugs. Here we report that the lipid receptor GPR55 is highly expressed by splenic B cells and inversely correlates with atheroma plaque size in mice. In human carotid endarterectomy specimen, GPR55 transcript levels were significantly lower in unstable compared to stable carotid plaques. To study the impact of GPR55 deficiency in atherosclerosis, we crossed Gpr55 knockout mice with apolipoprotein E (ApoE) knockout mice and subjected the mice to Western diet for 4 to 16 weeks. Compared to ApoE-/- controls, ApoE-/-Gpr55-/- mice developed larger plaques with increased necrotic core size, associated with elevated circulating and aortic leukocyte counts. Flow cytometry, immunofluorescence and RNA-sequencing analysis of splenic B cells in these mice revealed a hyperactivated B cell phenotype with disturbed plasma cell maturation and immunoglobulin (Ig)G antibody overproduction. The specific contribution of B cell GPR55 in atherosclerosis was further studied in mixed Gpr55-/-/{micro}MT bone marrow chimeras on low density receptor deficiency (Ldlr-/-) background, revealing that B-cell specific depletion of Gpr55 was sufficient to promote plaque development. Conversely, adoptive transfer of wildtype B cells into ApoE-/-Gpr55-/- mice blunted the proatherogenic phenotype. In vitro stimulation of splenocytes with the endogenous GPR55 ligand LPI promoted plasma cell proliferation and enhanced B cell activation marker expression, which was inhibited by the GPR55 antagonist CID16020046. Collectively, these discoveries provide new evidence for GPR55 as key modulator of the adaptive immune response in atherosclerosis. Targeting GPR55 could be useful to limit inflammation and plaque progression in patients suffering from atherosclerosis.

immunology↗

bioRxiv2021

Protein content and lipid profiling of isolated native autophagosomes

Autophagy is a central eukaryotic catabolic pathway responsible for clearance and recycling of an extensive portfolio of cargoes, which are packed in vesicles, called autophagosomes, and are delivered to lysosomes for degradation. Besides basal autophagy, which constantly degrades cellular material, the pathway is highly responsive to several stress conditions. However, the exact protein content and phospholipid composition of autophagosomes under changing autophagy conditions remain elusive so far. Here, we introduce a FACS-based approach for isolation of native unmanipulated autophagosomes and ensure the quality of the preparations. Employing quantitative proteomics and phospholipidomics, we obtained a profound cargo and lipid profile of autophagosomes purified upon basal autophagy conditions, nutrient deprivation, and proteasome inhibition. Indeed, starvation only mildly affected the content profile, while interference with proteasome activity showed stronger effects and specifically altered autophagosome cargoes. Interestingly, the phospholipid composition of autophagosomes was unaffected by the different treatments. Thus, the novel isolation method enables purification of intact autophagosomes in large quantities and allows protein content and phospholipid profiling without the requirement of exhaustive cellular fractionation or genetic manipulation.

biochemistry↗