Effect of amiodarone on cytokine release and on enzyme activities of mouse alveolar macrophages, bone marrow macrophages, and blood monocytes.

SummaryThe pathogenesis of atherosclerosis involves the interplay of haematopoietic, stromal and endothelial cells. Platelet interactions with endothelium and leukocytes are pivotal for atherosclerosis promotion. Glycoprotein (GP) Ibα is the ligand-binding subunit of the platelet GPIb-IX-V receptor complex; its deficiency causes the Bernard-Soulier syndrome (BSS), characterised by absent platelet GPIb-IX-V, macrothrombocytopenia and bleeding. We designed this study to determine the role of platelet GPIbα in the pathogenesis of atherosclerosis using two unique knockout models. Ldlr-/- mice were reconstituted with wild-type (wt), GPIbα-/- (lacks GPIbα) or chimeric IL-4R/GPIbα-Tg (lacks GPIbα extracellular domain) bone marrow and assayed for atherosclerosis development after feeding with pro-atherogenic “western diet”. Here, we report that Ldlr-/- mice reconstituted with GPIbα-/- bone marrow developed less atherosclerosis compared to wt controls; accompanied by augmented accumulation of pro-inflammatory CD11b+ and CD11c+ myeloid cells, reduced oxLDL uptake and decreased TNF and IL 12p35 gene expression in the aortas. Flow cytometry and live cell imaging in whole blood-perfused microfluidic chambers revealed reduced platelet-monocyte aggregates in GPIbα-/- mice, which resulted in decreased monocyte activation. Interestingly, Ldlr -/- mice reconstituted with IL-4R/GPIbα-Tg bone marrow, producing less abnormal platelets, showed atherosclerotic lesions similar to wt mice. Platelet interaction with blood monocytes and accumulation of myeloid cells in the aortas were also essentially unaltered. Moreover, only complete GPIbα ablation altered platelet microparticles and CCL5 chemokine production. Thus, atherosclerosis reduction in mice lacking GPIbα may not result from the defective GPIbα-ligand binding, but more likely is a consequence of functional defects of GPIbα-/- platelets and reduced blood platelet counts.

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Toward functional proteomics of alveolar macrophages

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00305.2004 ◽

2005 ◽

Vol 288 (4) ◽

pp. L585-L595 ◽

Cited By ~ 16

Author(s):

Haifeng M. Wu ◽

Ming Jin ◽

Clay B. Marsh

Keyword(s):

Alveolar Macrophages ◽

Large Scale ◽

Cell Types ◽

Mononuclear Phagocyte ◽

Detection Sensitivity ◽

Current Status ◽

Blood Monocytes ◽

Protein Patterns ◽

Additional Information ◽

The Impact

Alveolar macrophages (AM) belong to a phenotype of macrophages with distinct biological functions and important pathophysiological roles in lung health and disease. The molecular details determining AM differentiation from blood monocytes and AM roles in lung homeostasis are largely unknown. With the use of different technological platforms, advances in the field of proteomics have made it possible to search for differences in protein expression between AM and their precursor monocytes. Proteome features of each cell type provide new clues into understanding mononuclear phagocyte biology. In-depth analyses using subproteomics and subcellular proteomics offer additional information by providing greater protein resolution and detection sensitivity. With the use of proteomic techniques, large-scale mapping of phosphorylation differences between the cell types have become possible. Furthermore, two-dimensional gel proteomics can detect germline protein variants and evaluate the impact of protein polymorphisms on an individual's susceptibility to disease. Finally, surface-enhanced laser desorption and ionization (SELDI) time-of-flight mass spectrometry offers an alternative method to recognizing differences in protein patterns between AM and monocytes or between AM under different pathological conditions. This review details the current status of this field and outlines future directions in functional proteomic analyses of AM and monocytes. Furthermore, this review presents viewpoints of integrating proteomics with translational topics in lung diseases to define the mechanisms of disease and to uncover new diagnostic and therapeutic targets.

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In vitro formation of osteoclasts from long-term cultures of bone marrow mononuclear phagocytes.

Journal of Experimental Medicine ◽

10.1084/jem.156.6.1604 ◽

1982 ◽

Vol 156 (6) ◽

pp. 1604-1614 ◽

Cited By ~ 231

Author(s):

E H Burger ◽

J W Van der Meer ◽

J S van de Gevel ◽

J C Gribnau ◽

G W Thesingh ◽

...

Keyword(s):

Bone Marrow ◽

Electron Microscopic Examination ◽

Osteoclast Formation ◽

Mononuclear Phagocytes ◽

Long Bone ◽

Embryonic Liver ◽

Blood Monocytes ◽

Electron Microscopic ◽

Embryonic Mouse

The origin of osteoclasts was studied in an in vitro model using organ cultures of periosteum-free embryonic mouse long-bone primordia, which were co-cultured with various cell populations. The bone rudiments were freed of their periosteum-perichondrium by collagenase treatment in a stage before cartilage erosion and osteoclast formation, and co-cultured for 7 d with either embryonic liver or mononuclear phagocytes from various sources. Light and electron microscopic examination of the cultures showed that mineralized matrix-resorbing osteoclasts developed only in bones co-cultured with embryonic liver or with cultured bone marrow mononuclear phagocytes but not when co-cultured with blood monocytes or resident or exudate peritoneal macrophages. Osteoclasts developed from the weakly adherent, but not from the strongly adherent cells of bone marrow cultures, whereas 1,000 rad irradiation destroyed the capacity of such cultures to form osteoclasts. In bone cultures to which no other cells were added, osteoclasts were virtually absent. Bone-resorbing activity of in vitro formed osteoclasts was demonstrated by 45Ca release studies. These studies demonstrate that osteoclasts develop from cells present in cultures of proliferating mononuclear phagocytes and that, at least in our system, monocytes and macrophages are unable to form osteoclasts. The most likely candidates for osteoclast precursor cells seem to be monoblasts and promonocytes.

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