Two-dimensional and three-dimensional movement of human polymorphonuclear leukocytes: two fundamentally different

Insights

Polymorphonuclear leukocytes (PMNLs) lacking specific adherence glycoproteins show impaired 2D movement but normal 3D movement. This suggests distinct adherence-dependent and independent mechanisms govern cell migration in different environments.

Area of Science:

  • Immunology
  • Cell Biology
  • Biochemistry

Background:

  • Patients with inherited deficiencies in LFA-1, Mac-1, and p150,95 glycoproteins cannot mobilize polymorphonuclear leukocytes (PMNLs) to inflammatory sites.
  • These deficiencies profoundly impair PMNL movement on two-dimensional surfaces but show less effect on three-dimensional movement through filters.

Purpose of the Study:

  • To investigate the differential impact of adherence glycoproteins on PMNL migration in two-dimensional versus three-dimensional environments.
  • To explore the mechanisms underlying adherence-dependent and independent cell motility.

Main Methods:

  • Assessed translational mobility of PMNLs from deficient patients and HL-60 cells in two-dimensional (plastic surfaces) and three-dimensional (cellulose filters, collagen gels) matrices.
  • Utilized antibodies against the common beta subunit to block cell movement.
  • Induced Mac-1 and p150,95 expression on HL-60 cells to study adherence effects on motility.

Main Results:

  • PMNLs deficient in LFA-1/Mac-1/p150,95 showed impaired two-dimensional movement but normal movement in collagen gels, indicating adherence independence in 3D.
  • Antibodies against the common beta subunit blocked 2D movement but minimally affected 3D movement.
  • Induced adherence in HL-60 cells did not enhance translational movement, highlighting factors beyond mere adherence.

Conclusions:

  • PMNLs exhibit two distinct migratory modes: adherence-dependent (2D) and largely adherence-independent (3D).
  • These findings support the hypothesis that PMNL extravasation from vasculature is adherence-dependent, while migration through tissues is adherence-independent.

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