Linked Life Data

7081427

Source:http://linkedlifedata.com/resource/pubmed/id/7081427

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1982-7-8
pubmed:abstractText
An improved radioassay for analysis of phagocytosis has been used to quantitate and characterize the binding and internalization of zymosan by monolayers of rabbit pulmonary alveolar macrophages. This method distinguishes zymosan particles reversibly bound to the cell surface from those internalized. The zymosan was radiolabeled with technetium 99m(99mTc), a gamma-emitter with a 6-h half-life. Use of 99mTc as the radiolabel also permitted simultaneous determinations of pinocytosis and cellular protein content using [14C]sucrose and [3H]amino acids, respectively. All endocytic data were normalized per adherent cell based on this latter measurement. A significant fraction of the cell-associated particles was bound to the cell surface but not internalized. Failure to correct for this compartment would have resulted in overestimation of phagocytic rate and total cellular capacity. Both binding and ingestion of functionally unopsonized zymosan were found to be saturable, temperature sensitive, dependent on glycolytic energy, dependent on a trypsin-sensitive membrane component, described by a maximal rate, and limited by a finite capacity. The time courses of both processes were found to be similar. These results led us to conclude that, in our system, both binding and internalization were active processes and that the limited capacity to ingest zymosan was not explained by a concomitant reduction in binding of the particle to the cell membrane. Furthermore, it was found that phagocytosis did not change the rate of fluid-phase pinocytosis, consistent with the concept that the cell membrane is a functional mosaic as has been previously found by others for phagocytic and transport sites in this cell type.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
242
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C339-46
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
Macrophage phagocytosis: analysis of particle binding and internalization.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.