SP-A enhances uptake of bacillus Calmette-Guerin by macrophages through a specific SP-A receptor

Laura F. Weikert, Kathryn Edwards, Zissis C. Chroneos, Cynthia Hager, Loren Hoffman, Virginia L. Shepherd

Research output: Contribution to journalArticle

92 Citations (Scopus)

Abstract

Surfactant-associated protein A (SP-A) is a C-type lectin that is involved in surfactant metabolism as well as host defense functions in the lung. We have recently identified a receptor on macrophages [specific 210- kDa SP-A receptor (SPR210)] that binds SP-A. In the current study we have investigated the role of SP-A in mediating uptake of bacillus Calmette- Guerin (BCG) by rat macrophages and human monocytes and have examined the role of the macrophage SPR210 in this process. 125I-labeled SP-A bound BCG in a Ca2+, carbohydrate-, and dose-dependent manner. To examine association of SP-A-BCG complexes with macrophages, BCG were opsonized with SP-A and were incubated with rat bone marrow-derived macrophages (RBMM), rat alveolar macrophages (RAM), or human monocytes at a 1-to-1 ratio for 4 h. The cells were washed, fixed in formalin, and stained with auramine-rhodamine. Cell- associated organisms were enumerated by fluorescent microscopy. The percentage of cells with one or more associated BCG was increased by SP-A from 27% of RBMM with BCG alone to 54% with SP-A-BCG complexes; 1-16% in RAM; and 39-67% in human monocytes. This enhanced uptake was dependent on the dose of SP-A, with maximal increases seen with 10 μ/ml. Electron microscopic analysis supported the conclusion that organisms were ingested by and not simply bound to the macrophages. Inclusion of SPR210 antibodies blocked association of SP-A-BCG complexes, suggesting a role for SPR210 in mediating the interaction of SP-A-BCG with the macrophages. This was further supported by the finding that modulation of SPR210 activity resulted in altered SPoA- BCG uptake. These results demonstrate that SP-A binds to BCG and that uptake of these SP-A-BCG complexes is mediated in part by the SPR210 on rat macrophages and human monocytes.

Original languageEnglish (US)
Pages (from-to)L989-L995
JournalAmerican Journal of Physiology - Lung Cellular and Molecular Physiology
Volume272
Issue number5 16-5
StatePublished - May 1 1997

Fingerprint

Staphylococcal Protein A
Mycobacterium bovis
Surface-Active Agents
Macrophages
Monocytes
Alveolar Macrophages
surfactant protein A receptor
Benzophenoneidum
C-Type Lectins
Rhodamines
Formaldehyde
Microscopy
Carbohydrates

All Science Journal Classification (ASJC) codes

  • Physiology
  • Pulmonary and Respiratory Medicine
  • Physiology (medical)
  • Cell Biology

Cite this

Weikert, Laura F. ; Edwards, Kathryn ; Chroneos, Zissis C. ; Hager, Cynthia ; Hoffman, Loren ; Shepherd, Virginia L. / SP-A enhances uptake of bacillus Calmette-Guerin by macrophages through a specific SP-A receptor. In: American Journal of Physiology - Lung Cellular and Molecular Physiology. 1997 ; Vol. 272, No. 5 16-5. pp. L989-L995.
@article{7e3a92f4169b4a9fbbb7cbfec3ac9fbf,
title = "SP-A enhances uptake of bacillus Calmette-Guerin by macrophages through a specific SP-A receptor",
abstract = "Surfactant-associated protein A (SP-A) is a C-type lectin that is involved in surfactant metabolism as well as host defense functions in the lung. We have recently identified a receptor on macrophages [specific 210- kDa SP-A receptor (SPR210)] that binds SP-A. In the current study we have investigated the role of SP-A in mediating uptake of bacillus Calmette- Guerin (BCG) by rat macrophages and human monocytes and have examined the role of the macrophage SPR210 in this process. 125I-labeled SP-A bound BCG in a Ca2+, carbohydrate-, and dose-dependent manner. To examine association of SP-A-BCG complexes with macrophages, BCG were opsonized with SP-A and were incubated with rat bone marrow-derived macrophages (RBMM), rat alveolar macrophages (RAM), or human monocytes at a 1-to-1 ratio for 4 h. The cells were washed, fixed in formalin, and stained with auramine-rhodamine. Cell- associated organisms were enumerated by fluorescent microscopy. The percentage of cells with one or more associated BCG was increased by SP-A from 27{\%} of RBMM with BCG alone to 54{\%} with SP-A-BCG complexes; 1-16{\%} in RAM; and 39-67{\%} in human monocytes. This enhanced uptake was dependent on the dose of SP-A, with maximal increases seen with 10 μ/ml. Electron microscopic analysis supported the conclusion that organisms were ingested by and not simply bound to the macrophages. Inclusion of SPR210 antibodies blocked association of SP-A-BCG complexes, suggesting a role for SPR210 in mediating the interaction of SP-A-BCG with the macrophages. This was further supported by the finding that modulation of SPR210 activity resulted in altered SPoA- BCG uptake. These results demonstrate that SP-A binds to BCG and that uptake of these SP-A-BCG complexes is mediated in part by the SPR210 on rat macrophages and human monocytes.",
author = "Weikert, {Laura F.} and Kathryn Edwards and Chroneos, {Zissis C.} and Cynthia Hager and Loren Hoffman and Shepherd, {Virginia L.}",
year = "1997",
month = "5",
day = "1",
language = "English (US)",
volume = "272",
pages = "L989--L995",
journal = "American Journal of Physiology",
issn = "1040-0605",
publisher = "American Physiological Society",
number = "5 16-5",

}

SP-A enhances uptake of bacillus Calmette-Guerin by macrophages through a specific SP-A receptor. / Weikert, Laura F.; Edwards, Kathryn; Chroneos, Zissis C.; Hager, Cynthia; Hoffman, Loren; Shepherd, Virginia L.

In: American Journal of Physiology - Lung Cellular and Molecular Physiology, Vol. 272, No. 5 16-5, 01.05.1997, p. L989-L995.

Research output: Contribution to journalArticle

TY - JOUR

T1 - SP-A enhances uptake of bacillus Calmette-Guerin by macrophages through a specific SP-A receptor

AU - Weikert, Laura F.

AU - Edwards, Kathryn

AU - Chroneos, Zissis C.

AU - Hager, Cynthia

AU - Hoffman, Loren

AU - Shepherd, Virginia L.

PY - 1997/5/1

Y1 - 1997/5/1

N2 - Surfactant-associated protein A (SP-A) is a C-type lectin that is involved in surfactant metabolism as well as host defense functions in the lung. We have recently identified a receptor on macrophages [specific 210- kDa SP-A receptor (SPR210)] that binds SP-A. In the current study we have investigated the role of SP-A in mediating uptake of bacillus Calmette- Guerin (BCG) by rat macrophages and human monocytes and have examined the role of the macrophage SPR210 in this process. 125I-labeled SP-A bound BCG in a Ca2+, carbohydrate-, and dose-dependent manner. To examine association of SP-A-BCG complexes with macrophages, BCG were opsonized with SP-A and were incubated with rat bone marrow-derived macrophages (RBMM), rat alveolar macrophages (RAM), or human monocytes at a 1-to-1 ratio for 4 h. The cells were washed, fixed in formalin, and stained with auramine-rhodamine. Cell- associated organisms were enumerated by fluorescent microscopy. The percentage of cells with one or more associated BCG was increased by SP-A from 27% of RBMM with BCG alone to 54% with SP-A-BCG complexes; 1-16% in RAM; and 39-67% in human monocytes. This enhanced uptake was dependent on the dose of SP-A, with maximal increases seen with 10 μ/ml. Electron microscopic analysis supported the conclusion that organisms were ingested by and not simply bound to the macrophages. Inclusion of SPR210 antibodies blocked association of SP-A-BCG complexes, suggesting a role for SPR210 in mediating the interaction of SP-A-BCG with the macrophages. This was further supported by the finding that modulation of SPR210 activity resulted in altered SPoA- BCG uptake. These results demonstrate that SP-A binds to BCG and that uptake of these SP-A-BCG complexes is mediated in part by the SPR210 on rat macrophages and human monocytes.

AB - Surfactant-associated protein A (SP-A) is a C-type lectin that is involved in surfactant metabolism as well as host defense functions in the lung. We have recently identified a receptor on macrophages [specific 210- kDa SP-A receptor (SPR210)] that binds SP-A. In the current study we have investigated the role of SP-A in mediating uptake of bacillus Calmette- Guerin (BCG) by rat macrophages and human monocytes and have examined the role of the macrophage SPR210 in this process. 125I-labeled SP-A bound BCG in a Ca2+, carbohydrate-, and dose-dependent manner. To examine association of SP-A-BCG complexes with macrophages, BCG were opsonized with SP-A and were incubated with rat bone marrow-derived macrophages (RBMM), rat alveolar macrophages (RAM), or human monocytes at a 1-to-1 ratio for 4 h. The cells were washed, fixed in formalin, and stained with auramine-rhodamine. Cell- associated organisms were enumerated by fluorescent microscopy. The percentage of cells with one or more associated BCG was increased by SP-A from 27% of RBMM with BCG alone to 54% with SP-A-BCG complexes; 1-16% in RAM; and 39-67% in human monocytes. This enhanced uptake was dependent on the dose of SP-A, with maximal increases seen with 10 μ/ml. Electron microscopic analysis supported the conclusion that organisms were ingested by and not simply bound to the macrophages. Inclusion of SPR210 antibodies blocked association of SP-A-BCG complexes, suggesting a role for SPR210 in mediating the interaction of SP-A-BCG with the macrophages. This was further supported by the finding that modulation of SPR210 activity resulted in altered SPoA- BCG uptake. These results demonstrate that SP-A binds to BCG and that uptake of these SP-A-BCG complexes is mediated in part by the SPR210 on rat macrophages and human monocytes.

UR - http://www.scopus.com/inward/record.url?scp=0030915464&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030915464&partnerID=8YFLogxK

M3 - Article

C2 - 9176265

AN - SCOPUS:0030915464

VL - 272

SP - L989-L995

JO - American Journal of Physiology

JF - American Journal of Physiology

SN - 1040-0605

IS - 5 16-5

ER -