Related Experiment Video
Updated: Sep 9, 2026
Laminar Flow-based Assays to Investigate Leukocyte Recruitment on Cultured Vascular Cells and Adherent Platelets
Published on: April 9, 2018
Factors affecting the adhesiveness of human leucocytes and platelets in vitro
Abstract:
Some factors affecting the retention of human polymorphonuclear neutrophils (PMN), lymphocytes, and platelets on a siliconized glass bead column were explored. PMN were more effectively retained when the flow rates were slow and the columns long. They were found largely on the upper portions of the columns except with rapid flow rates when they spread down the columns. PMN retention on the columns was greatest in the range 30 degrees -43 degrees C. Both magnesium and calcium ions were required for full adhesiveness; calcium ions alone were unable to restore adhesiveness to PMN from blood which had been treated with a chelating resin to remove divalent cations. The adhesiveness of the PMN was independent of cyanide and dinitrophenol, but was almost completely eliminated by iodoacetamide. Under all the conditions mentioned above in which adhesiveness was lost there was a concurrent loss of the usual ability of the PMN to migrate, but at least in the presence of EDTA, a capacity to change shape by pseudopod formation remained. Lymphocytes were retained on the columns to a much lesser extent than the PMN under all conditions and, within limits, this retention was not related to either flow rate or column length. Maximum lymphocyte retention occurred in the range 30 degrees -43 degrees C. No dependence of lymphocyte adhesiveness was shown for divalent cations, cyanide, dinitrophenol, or iodoacetamide, but such dependence is not excluded by the data obtained. Platelets were largely retained by the glass bead columns under most conditions and this was unrelated to temperature in the range 0 degrees -50 degrees C. Their adhesiveness was found to require either magnesium or calcium ions and to be blocked by iodoacetamide.
Insights
Human polymorphonuclear neutrophils (PMN), lymphocytes, and platelets show varied retention on glass bead columns. PMN retention depends on flow rate, temperature, and divalent cations like magnesium and calcium for optimal adhesiveness.
Area of Science:
- Hematology
- Cellular Biology
- Biophysics
Background:
- Understanding cell adhesion is crucial for various biological processes and medical applications.
- Previous research has explored cell retention but specific factors for different blood cell types require further elucidation.
Purpose of the Study:
- To investigate factors influencing the retention of human polymorphonuclear neutrophils (PMN), lymphocytes, and platelets on siliconized glass bead columns.
- To determine the roles of flow rate, column length, temperature, and ionic composition on cell adhesion.
Main Methods:
- Utilized siliconized glass bead columns to assess cell retention.
- Varied flow rates, column lengths, and temperatures to observe effects on cell adhesion.
- Investigated the impact of divalent cations (magnesium, calcium), chelating agents (EDTA), and metabolic inhibitors (iodoacetamide, cyanide, dinitrophenol) on cell adhesiveness.
Main Results:
- PMN retention was highest with slow flow rates, long columns, and temperatures between 30-43°C, requiring both magnesium and calcium ions for full adhesiveness.
- Lymphocyte retention was less than PMN and not significantly affected by flow rate or column length, with peak retention at 30-43°C.
- Platelet retention was high across tested temperatures (0-50°C) and required magnesium or calcium ions, with adhesiveness blocked by iodoacetamide.
Conclusions:
- Cellular retention on glass bead columns is cell-type specific and influenced by physical and chemical factors.
- PMN adhesiveness is an active process dependent on divalent cations and cellular metabolism, while platelet adhesion requires specific ions.
- Findings provide insights into the biophysical properties of blood cells and their interactions with surfaces.
