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Biology subjects

Lindquist, R. L.

Publications and source records attributed to Lindquist, R. L..

3 recordsLinked to original sources

Low-Density Granulocytes are a novel immunopathological feature in both Multiple Sclerosis and Neuromyelitis optica spectrum disorder.

ObjectiveTo investigate whether low-density granulocytes (LDGs) are a immunophenotypic feature of patients with multiple sclerosis (MS) and/or neuromyelitis optica spectrum disorder (NMOSD).\n\nMethodsBlood samples were collected from 26 patients with NMOSD and 20 patients with MS, as well as from 18 patients with Systemic Lupus Erythematosus (SLE) and 23 Healthy Donors (HD). We isolated peripheral blood mononuclear cells (PBMCs) with density gradient separation and stained the cells with antibodies against CD14, CD15, CD16, and CD45, and analysed the cells by flow cytometry or imaging flow cytometry. We defined LDGs as CD14-CD15high and calculated their share in total PBMC leukocytes (CD45+) as well as the share of CD16hi LDGs. Clinical data on disease course, medication, and antibody status were obtained.\n\nResultsLDGs were significantly more common in MS and NMOSD than in HDs, comparable to SLE samples (median values HD 0.2%, MS 0.9%, NMOSD 2.1%, SLE 4.3%). 0/23 of the HDs, but 17/20 NMOSD and 11/17 MS samples as well as 13/15 SLE samples had at least 0.7 % LDGs. NMOSD patients without continuous immunosuppressive treatment had significantly more LDGs compared to their treated counterparts. LDG nuclear morphology ranged from segmented to rounded, suggesting a heterogeneity within the group.\n\nConclusionLDGs are a feature of the immunophenotype in some patients with MS and NMOSD.

immunology↗

Single-cell RNA-sequencing redefines blood cell type classification in mosquitoes

Mosquito blood cells are ancestral immune cells that help control infection by vector-borne pathogens. Despite their importance, little is known about mosquito blood cell biology beyond the ambiguous morphological and functional criteria used for their classification. Here we combined the power of single-cell RNA-sequencing, imaging flow cytometry and single-molecule RNA hybridization to analyze blood cells of the malaria mosquito Anopheles gambiae. By demonstrating that blood cells express nearly half of the mosquito transcriptome, our dataset represents an unprecedented view into their transcriptional machinery. Analyses of differentially expressed genes identified transcriptional signatures of two distinct cell types that challenge the current morphology-based classification of these cells. We further demonstrated an active transfer of a cellular marker between blood cells that confounds their identity. We propose that cell-to-cell exchange is broadly relevant for cell type classification and may account for the remarkable cellular diversity observed in nature.

immunology↗

Mosquito lipids regulate Plasmodium sporogony and infectivity to the mammalian host

Malaria is a fatal human parasitic disease transmitted by a mosquito vector. The evolution of within-host malaria virulence has been the focus of many empirical and theoretical studies. However, the vectors contribution to virulence evolution is not well understood. Here we explored how within-vector resource exploitation impacts evolutionary trajectories of within-host Plasmodium virulence. We developed a nested model of within-vector dynamics and malaria epidemiology, which predicted that non-competitive resource exploitation within-vector restricts within-host parasite virulence. To validate our model, we experimentally manipulated mosquito lipid trafficking and gauged within-vector parasite development, within-host infectivity and virulence. We found that mosquito-derived lipids determine within-host parasite virulence by shaping development and metabolic activity of transmissible sporozoites. Our findings uncover the role of within-vector environment in regulating within-host Plasmodium virulence and identify Plasmodium metabolic traits that may contribute to the evolution of malaria virulence.

microbiology↗