Dataset Information

Phenotypic and Functional Heterogeneity of Low-Density and High-Density Human Lung Macrophages.

ABSTRACT: Pulmonary macrophages are a highly heterogeneous cell population distributed in different lung compartments. We separated two subpopulations of macrophages from human lung parenchyma according to flotation over density gradients. Two-thirds 65.4% of the lung macrophages have a density between 1.065 and 1.078 (high-density macrophages: HDMs), and the remaining one-third (34.6) had a density between 1.039 and 1.052 (low-density macrophages: LDMs). LDMs had a larger area (691 vs. 462 μm2) and cell perimeter (94 vs. 77 μm) compared to HDMs. A significantly higher percentage of HDMs expressed CD40, CD45, and CD86 compared to LDMs. In contrast, a higher percentage of LDMs expressed the activation markers CD63 and CD64. The release of TNF-α, IL-6, IL-10 and IL-12 induced by lipopolysaccharide (LPS) was significantly higher in HDMs than in LDMs. The human lung contains two subpopulations of macrophages that differ in buoyancy, morphometric parameters, surface marker expression and response to LPS. These subpopulations of macrophages probably play distinct roles in lung inflammation and immune responses.

SUBMITTER: Balestrieri B

PROVIDER: S-EPMC8147777 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Phenotypic and Functional Heterogeneity of Low-Density and High-Density Human Lung Macrophages.

Balestrieri Barbara B Granata Francescopaolo F Loffredo Stefania S Petraroli Angelica A Scalia Giulia G Morabito Paolo P Cardamone Chiara C Varricchi Gilda G Triggiani Massimo M

Biomedicines 20210504 5

<h4>Background</h4>Pulmonary macrophages are a highly heterogeneous cell population distributed in different lung compartments.<h4>Methods</h4>We separated two subpopulations of macrophages from human lung parenchyma according to flotation over density gradients.<h4>Results</h4>Two-thirds 65.4% of the lung macrophages have a density between 1.065 and 1.078 (high-density macrophages: HDMs), and the remaining one-third (34.6) had a density between 1.039 and 1.052 (low-density macrophages: LDMs). L ...[more]

PMID: 34064389

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Dataset Information

Phenotypic and Functional Heterogeneity of Low-Density and High-Density Human Lung Macrophages.

Publications

Phenotypic and Functional Heterogeneity of Low-Density and High-Density Human Lung Macrophages.

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