Influence of oxygen tension and hematocrit reading on ESRs of sickle cells. Role of RBC aggregation

Jan, K.

doi:10.1001/archinte.141.13.1815

“…In contrast, (ii) also the erythrocyte shape and rigidity contributes to the ESR. Irregular shaped or rigidified cells, like sickle cells (Jan et al, 1981;Lawrence and Fabry, 1986) or acanthocytes (Salt et al, 1960) decrease the ESR. Although there is no lower limit established as a pathological limit, a low ESR was proposed as a biomarker for diseases belonging to the neuroacanthocytosis syndrome (NAS) (Darras et al, 2021a;Rabe et al, 2021).…”

Section: Introductionmentioning

confidence: 99%

Imaging Erythrocyte Sedimentation in Whole Blood

Darras

¹

,

Breunig

²

,

John

³

et al. 2022

View full text Add to dashboard Cite

The erythrocyte sedimentation rate (ESR) is one of the oldest medical diagnostic tools. However, currently there is some debate on the structure formed by the cells during the sedimentation process. While the conventional view is that erythrocytes sediment as separate aggregates, others have suggested that they form a percolating gel, similar to other colloidal suspensions. However, visualization of aggregated erythrocytes, which would settle the question, has always been challenging. Direct methods usually study erythrocytes in 2D situations or low hematocrit (∼1%). Indirect methods, such as scattering or electric measurements, provide insight on the suspension evolution, but cannot directly discriminate between open or percolating structures. Here, we achieved a direct probing of the structures formed by erythrocytes in blood at stasis. We focused on blood samples at rest with controlled hematocrit of 45%, from healthy donors, and report observations from three different optical imaging techniques: direct light transmission through thin samples, two-photon microscopy and light-sheet microscopy. The three techniques, used in geometries with thickness from 150 μm to 3 mm, highlight that erythrocytes form a continuous network with characteristic cracks, i.e., a colloidal gel. The characteristic distance between the main cracks is of the order of ∼100 μm. A complete description of the structure then requires a field of view of the order of ∼1 mm, in order to obtain a statistically relevant number of structural elements. A quantitative analysis of the erythrocyte related processes and interactions during the sedimentation need a further refinement of the experimental set-ups.

show abstract

“…In contrast, (ii) also the erythrocyte shape contributes to the ESR. Irregular cell shapes, like sickle cells (Jan et al, 1981; Lawrence and Fabry, 1986) or acanthocytes (Salt et al, 1960) decrease the ESR. Although there is no lower limit established as a pathological limit, a low ESR was proposed as a biomarker for diseases belonging to the neuroacanthocytosis syndrome (NAS) (Darras et al, 2021; Rabe et al, 2021).…”

Section: Introductionmentioning

confidence: 99%

Imaging erythrocyte sedimentation in whole blood

Darras

¹

,

Breunig

²

,

John

³

et al. 2021

Preprint

0

View full text Add to dashboard Cite

The erythrocyte sedimentation rate (ESR) is one of the oldest medical diagnostic tools. However, currently there is some debate on the structure formed by the cells during the sedimentation process. While the conventional view is that erythrocytes sediment as separate aggregates, others have suggested that they form a percolating gel, similar to other colloidal suspensions. A direct probing of the structures formed by erythrocytes in blood at stasis is then required to settle these discrepancies. Here, we report observations performed with three different optical imaging techniques: direct light transmission through thin samples, two-photon microscopy and light-sheet microscopy. All techniques revealed a dynamic structure of a channeling gel but with differences in the resolved details. A quantitative analysis of the erythrocyte related processes and interactions during the sedimentation need a further refinement of the experimental set-ups.

show abstract