Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001511 (Adhesion)
 5,955 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Class A scavenger receptors (SR-A) mediate microglial interaction with fibrillar beta-amyloid (fAbeta). We report here that neonatal microglia from SR-A knockout mice (SR-A-/-) adhere to surface-bound fAbeta, and produce reactive oxygen species (ROS) as efficiently as wildtype microglia; that both wildtype and SR-A-/- microglia express SR-BI; that antibodies against SR-BI do not affect adhesion or ROS production by wildtype microglia, but inhibit adhesion and ROS production of SR-A-/- microglia to immobilized fAbeta by approximately 40%. Adhesion to fAbeta-coated surfaces, and uptake of fAbeta by both wildtype and SR-A-/- microglia was almost completely inhibited by incubation with fucoidan. Thus SR-BI and SR-A mediate similar effector functions in neonatal microglia, which suggests that SR-BI plays as important a role as SR-A, and can maintain the wildtype phenotype in SR-A-/- microglia.
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PMID:Scavenger receptor class B type I (SR-BI) mediates adhesion of neonatal murine microglia to fibrillar beta-amyloid. 1124 25

Astrocytes and microglia associate to amyloid plaques, a pathological hallmark of Alzheimer disease. Microglia are activated by and can phagocytose beta-amyloid (Abeta). Scavenger receptors (SRs) are among the receptors mediating the uptake of fibrillar Abeta in vitro. However, little is known about the function of the astrocytes surrounding the plaques or the nature of their interaction with Abeta. It is unknown whether glial cells bind to nonfibrillar Abeta and if binding of astrocytes to Abeta depends on the same Scavenger receptors described for microglia. We determined the binding of glia to Abeta by an adhesion assay and evaluated the presence of scavenger receptors in glial cells by immunocytochemistry, immunohistochemistry of brain sections, and immunoblot. We found that astrocytes and microglia from neonatal rats adhered in a concentration-dependent manner to surfaces coated with fibrillar Abeta or nonfibrillar Abeta. Fucoidan and poly(I), known ligands for SR-type A, inhibited adhesion of microglia and astrocytes to Abeta and also inhibited Abeta phagocytosis. In contrast, a ligand for SR-type B like low density lipoprotein, did not compete glial adhesion to Abeta. Microglia presented immunodetectable SR-BI, SR-AI/AII, RAGE, and SR-MARCO (macrophage receptor with collagenous structure, a member of the SR-A family). Astrocytes presented SR-BI and SR-MARCO. To our knowledge, this is the first description of the presence of SR-MARCO in astrocytes. Our results indicate that both microglia and astrocytes adhere to fibrillar and nonfibrillar Abeta. Adhesion was mediated by a fucoidan-sensitive receptor. We propose that SR-MARCO could be the Scavenger receptor responsible for the adhesion of astrocytes and microglia to Abeta.
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PMID:Expression of scavenger receptors in glial cells. Comparing the adhesion of astrocytes and microglia from neonatal rats to surface-bound beta-amyloid. 1598 91