Membrane knobs are required for the microcirculatory obstruction induced by Plasmodium falciparum-infected erythrocytes

C. Raventos-Suarez, D. K. Kaul, Frank P. Macaluso, R. L. Nagel

Research output: Contribution to journalArticle

104 Citations (Scopus)

Abstract

We have studied the pathophysiology of the vascular obstruction induced by Plasmodium falciparum-parasitized erythrocytes with the use of an ex vivo microcirculatory preparation perfused with red cells infected with knobless and knobby clones of the FCR-3 strain. We find that parasitized erythrocyte membrane knobs are indispensable for the generation of the circulatory obstruction. Uninfected erythrocytes incubated in culture and erythrocytes infected with early or late forms of the knobless clones or the early forms of the knobby clone all failed to obstruct the microcirculation, although exhibiting various effects on bulk viscosity and peripheral resistance during flow. In contrast, late forms of the knobby clone produced significantly higher peripheral resistance during flow and significant obstruction as detected by changes in time of pressure flow recovery as well as by direct videorecorded microscopic observation. Optical and electron microscopy showed that the adherence of parasitized cells to the endothelium was limited to the venules and involved the knobs in junctions. In addition, we were able to follow the sequence of events during obstruction: initial red-cell adherence to the venular endothelium (sometimes only transitory) followed by progressive recruitment at the venule surface, finally leading to total obstruction that involved parasitized and nonparasitized erythrocytes. Sometimes, retrograde aggregation would extend the obstruction to the capillaries or even precapillary arterioles. These results show that knobs are necessary and sufficient to produce vascular obstruction and that other factors (spleen, immunological, etc.) can only have a modulating role. These results also exclude the possibility that the exclusive adherence to venules is the consequence of 'plasma factors' found in the malaric patients.

Original languageEnglish (US)
Pages (from-to)3829-3833
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Volume82
Issue number11
StatePublished - 1985

Fingerprint

Plasmodium falciparum
Venules
Clone Cells
Erythrocytes
Membranes
Vascular Resistance
Endothelium
Blood Vessels
Immunologic Factors
Erythrocyte Membrane
Arterioles
Microcirculation
Viscosity
Electron Microscopy
Spleen
Pressure

ASJC Scopus subject areas

  • General
  • Genetics

Cite this

@article{1238d2bf0a1249a9b6f53092d7502bae,
title = "Membrane knobs are required for the microcirculatory obstruction induced by Plasmodium falciparum-infected erythrocytes",
abstract = "We have studied the pathophysiology of the vascular obstruction induced by Plasmodium falciparum-parasitized erythrocytes with the use of an ex vivo microcirculatory preparation perfused with red cells infected with knobless and knobby clones of the FCR-3 strain. We find that parasitized erythrocyte membrane knobs are indispensable for the generation of the circulatory obstruction. Uninfected erythrocytes incubated in culture and erythrocytes infected with early or late forms of the knobless clones or the early forms of the knobby clone all failed to obstruct the microcirculation, although exhibiting various effects on bulk viscosity and peripheral resistance during flow. In contrast, late forms of the knobby clone produced significantly higher peripheral resistance during flow and significant obstruction as detected by changes in time of pressure flow recovery as well as by direct videorecorded microscopic observation. Optical and electron microscopy showed that the adherence of parasitized cells to the endothelium was limited to the venules and involved the knobs in junctions. In addition, we were able to follow the sequence of events during obstruction: initial red-cell adherence to the venular endothelium (sometimes only transitory) followed by progressive recruitment at the venule surface, finally leading to total obstruction that involved parasitized and nonparasitized erythrocytes. Sometimes, retrograde aggregation would extend the obstruction to the capillaries or even precapillary arterioles. These results show that knobs are necessary and sufficient to produce vascular obstruction and that other factors (spleen, immunological, etc.) can only have a modulating role. These results also exclude the possibility that the exclusive adherence to venules is the consequence of 'plasma factors' found in the malaric patients.",
author = "C. Raventos-Suarez and Kaul, {D. K.} and Macaluso, {Frank P.} and Nagel, {R. L.}",
year = "1985",
language = "English (US)",
volume = "82",
pages = "3829--3833",
journal = "Proceedings of the National Academy of Sciences of the United States of America",
issn = "0027-8424",
number = "11",

}

TY - JOUR

T1 - Membrane knobs are required for the microcirculatory obstruction induced by Plasmodium falciparum-infected erythrocytes

AU - Raventos-Suarez, C.

AU - Kaul, D. K.

AU - Macaluso, Frank P.

AU - Nagel, R. L.

PY - 1985

Y1 - 1985

N2 - We have studied the pathophysiology of the vascular obstruction induced by Plasmodium falciparum-parasitized erythrocytes with the use of an ex vivo microcirculatory preparation perfused with red cells infected with knobless and knobby clones of the FCR-3 strain. We find that parasitized erythrocyte membrane knobs are indispensable for the generation of the circulatory obstruction. Uninfected erythrocytes incubated in culture and erythrocytes infected with early or late forms of the knobless clones or the early forms of the knobby clone all failed to obstruct the microcirculation, although exhibiting various effects on bulk viscosity and peripheral resistance during flow. In contrast, late forms of the knobby clone produced significantly higher peripheral resistance during flow and significant obstruction as detected by changes in time of pressure flow recovery as well as by direct videorecorded microscopic observation. Optical and electron microscopy showed that the adherence of parasitized cells to the endothelium was limited to the venules and involved the knobs in junctions. In addition, we were able to follow the sequence of events during obstruction: initial red-cell adherence to the venular endothelium (sometimes only transitory) followed by progressive recruitment at the venule surface, finally leading to total obstruction that involved parasitized and nonparasitized erythrocytes. Sometimes, retrograde aggregation would extend the obstruction to the capillaries or even precapillary arterioles. These results show that knobs are necessary and sufficient to produce vascular obstruction and that other factors (spleen, immunological, etc.) can only have a modulating role. These results also exclude the possibility that the exclusive adherence to venules is the consequence of 'plasma factors' found in the malaric patients.

AB - We have studied the pathophysiology of the vascular obstruction induced by Plasmodium falciparum-parasitized erythrocytes with the use of an ex vivo microcirculatory preparation perfused with red cells infected with knobless and knobby clones of the FCR-3 strain. We find that parasitized erythrocyte membrane knobs are indispensable for the generation of the circulatory obstruction. Uninfected erythrocytes incubated in culture and erythrocytes infected with early or late forms of the knobless clones or the early forms of the knobby clone all failed to obstruct the microcirculation, although exhibiting various effects on bulk viscosity and peripheral resistance during flow. In contrast, late forms of the knobby clone produced significantly higher peripheral resistance during flow and significant obstruction as detected by changes in time of pressure flow recovery as well as by direct videorecorded microscopic observation. Optical and electron microscopy showed that the adherence of parasitized cells to the endothelium was limited to the venules and involved the knobs in junctions. In addition, we were able to follow the sequence of events during obstruction: initial red-cell adherence to the venular endothelium (sometimes only transitory) followed by progressive recruitment at the venule surface, finally leading to total obstruction that involved parasitized and nonparasitized erythrocytes. Sometimes, retrograde aggregation would extend the obstruction to the capillaries or even precapillary arterioles. These results show that knobs are necessary and sufficient to produce vascular obstruction and that other factors (spleen, immunological, etc.) can only have a modulating role. These results also exclude the possibility that the exclusive adherence to venules is the consequence of 'plasma factors' found in the malaric patients.

UR - http://www.scopus.com/inward/record.url?scp=0022363735&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0022363735&partnerID=8YFLogxK

M3 - Article

VL - 82

SP - 3829

EP - 3833

JO - Proceedings of the National Academy of Sciences of the United States of America

JF - Proceedings of the National Academy of Sciences of the United States of America

SN - 0027-8424

IS - 11

ER -