Subcellular localization of the large subunit of Mo1 (Mo1 alpha; formerly gp 110), a surface glycoprotein associated with neutrophil adhesion.

Abstract

Abstract. Mola (formerly gp 110) is a neutrophil glycoprotein whose deficiency is associated with abnormalities in several neutrophil functions, including defects in adherence, chemotaxis, and phagocytosis. Examination of whole cells and subcellular components by the use of both immunological and electrophoretic techniques demonstrated that Mo la was located primarily in the specific granules but that a small portion was present in the plasma membrane, where it is exposed to the extracellular environment and can bind to anti-Mo 1 antibody. During degranulation, Mola is translocated from the specific granules to the plasma membrane, resulting in a 5-10-fold increase in the surface expression of this glycoprotein. These findings plus previous work suggest that plasma membrane-associated Mole is needed for a normal interaction between neutrophils and underlying surfaces, and raise the possibility that the increase in surface adhesiveness of neutrophils that have discharged their specific granules might be due in part to the increase in the amount of Mo 1a in the plasma membranes of these degranulated cells.

Up-Regulation and Activation of Eosinophil Integrins in Blood and Airway after Segmental Lung Antigen Challenge

“…Dextran sedimentation during buffy coat preparation has been shown to cause up-regulation of ␣ M on blood eosinophils (and neutrophils) compared to that in whole, unfractionated blood (77). Eosinophils are likely similar to neutrophils, which are known to store a large proportion of ␣ M in granules, wherefrom it is translocated to the plasma membrane after cell stimulation (78). Remarkably, eosinophils in BAL had strong homogeneous labeling for ␤ 2 and ␣ M .…”

Human Leukaemic (HMC‐1) and Normal Skin Mast Cells Express β2‐Integrins: Characterization of β2‐Integrins and ICAM‐1 on HMC‐1 Cells

“…Mac-1 and p150,95 have been additionally reported to be modulated quantitatively by their rapid transportation from cytoplasmic granules to the plasma membrane upon appropriate cell stimulation [41][42][43][44]. An equivalent mechanism has not been reported for LFA-1, however.…”

Biochemical, Structural, and Functional Abnormalities of Polymorphonuclear Leukocytes in the Neonate

“…Recent evidence suggests that adherence of leukocytes to a substrate involves a series of surface glycoproteins (35)(36)(37). These glycoproteins share a common P chain that has a molecular weight of approximately 94 kD.…”