Polymorphonuclear Leukocyte Locomotion Research Articles

Swift transformation and locomotion of polymorphonuclear leukocytes and microglia as observed by VEC-DIC microscopy (video microscopy).

The detailed assembly used by us for video-enhanced contrast-differential interference contrast (VEC-DIC) microscopy (video microscopy is first described. Employing such video microscopy, we then examined the morphological changes occurring during locomotion and activation processes of polymorphonuclear leukocytes (PMNL) and microglia at an almost electron microscopic magnification. Upon contacting the substratum, PMNL transformed into a polarized ameboid shape and crawled extending pseudopodia, as has been well documented previously. The PMNL sometimes displayed a peculiar locomotion as if they were stepping on "tiny legs", or sliding on a treadmill of cell membrane. Cultured microglia were observed to exist in 4 forms; ramified, reactive, villous, and ameboid. Microglia in the reactive form pivoted, circled and crawled on the astroglial cell layer using their transparent lamellipodia with no morphological changes in their cell body. Unlike PMNL, reactive microglia exhibited no agitated movements of their intracellular organelles, including granules and cytosol, during locomotion. Lamellipodia on the undersurface of the cell body touching the cell layer adhesively, appeared to serve as the locomotive apparatus. When activated, both floating PMNL and microglia of villous form assumed an ameboid shape within a few seconds. Microglia occasionally swam in the medium waving their lamellipodia towards a target object (e.g. zymosan A particles), remodelling to an amorphous ameboid form and covering up the target. We attempt to discuss such swift morphological changes from the standpoint of thermodynamic potential of Gibbs free energy which is stored within the cells.

Stimulation of rabbit polymorphonuclear leukocyte locomotion by d-penicillamine

Treatment of polymorphonuclear leukocytes (PMNs) with penicillamine has little effect on chemotaxis of the cells towards fMet-Leu-Phe. In the absence of fMet-Leu-Phe however, penicillamine has a strong effect on PMN locomotion. Penicillamine-induced enhancement of PMN migration is for an important part due to a chemokinetic effect, but there is also a chemotactic effect. Pretreatment of PMNs with membrane-impermeable sulfhydryl reagents has little effect on random locomotion, but completely abolishes the activating effect of penicillamine. This suggests that for the activating effect of penicillamine intact sulfhydryl groups on the outer surface of the PMN are required. Extracellular calcium is no absolute requirement for PMN migration, neither for random locomotion nor for the activating effect of penicillamine. Removal of intracellular Ca 2+ with membrane-penetrating Ca 2+-complexing agents strongly inhibit penicillamine-induced enhancement of PMN migration, underlining a role for intracellular calcium. Penicillamine causes an increase of cGMP level in PMNs. Though a simple relationship seems unlikely it is possible that the enhancement of PMN migration, and the increase of cGMP level by penicillamine are related processes.

In vitro human polymorphonuclear leukocyte chemokinesis and human monocyte chemotaxis are different activities of aminoterminal and carboxyterminal substance P

Polymorphonuclear leukocytes (PMNL) are a component of the inflammatory response to neurogenic mediators. Using the micropore filter approach, the authors studied the chemoattracting properties of tachykinins, including substance P (SP), neurokinin A (NKA) and neurokinin B (NKB), and that of calcitonin gene-related peptide (CGRP) for human PMNL in vitro and now show that SP in near nanomolar concentrations stimulates locomotion of human PMNL. Locomotion of PMNL is induced by SP, aminoterminal SP (1-9) and the SP receptor antagonist [D-pro2, D-trp7,9]-SP (DPDT) but not by carboxyterminal SP (3-11), NKA, NKB, or CGRP suggesting that the aminoterminal amino acids arginine and proline are essential residues of SP in activation of PMNL locomotion. In contrast, the migratory effect of SP on monocytes resides in the carboxyterminal SP amino acid sequence, which is in agreement with carboxyterminal, SP receptor-mediated chemotaxis of human monocytes previously shown by others. From the known structure-activity relationships for SP receptors it is concluded that induction of PMNL migration by SP does not involve neurokinin-1 (NK-1), NK-2 or NK-3 receptors. "Checkerboard" analysis reveals that PMNL locomotion by SP is not dependent on concentration gradients and thus represents chemokinesis, which is enhancement of speed and/or frequency of locomotion. One cannot exclude that this action of SP on PMNL is mediated by the aminoterminal sequence via yet unknown SP "receptors".(ABSTRACT TRUNCATED AT 250 WORDS)

Polymorphonuclear leukocyte locomotion is insensitive to lowered cytoplasmic calcium levels.

Chemotactic factors stimulate the rate of locomotion of polymorphonuclear leukocytes (PMNs). To investigate the importance of cytoplasmic calcium we have examined the ability of the chemotactic peptide N-formylnorleucyl eucylphenalanine (FNLLP) to stimulate the locomotion of PMNs whose cytoplasmic calcium levels were reduced by incubation in EGTA or in EGTA plus the calcium ionophores, ionomycin or A23187. Locomotion was assayed by migration through micropore filters and by time-lapse videomicroscopy. Cells in EGTA exhibited similar or slightly reduced rates of locomotion compared to cells in Hanks' balanced salt solution (HBSS). The peptide dose dependence for the stimulation of locomotion was similar in medium containing calcium or EGTA. The presence of 1 microM ionophore plus EGTA had no effect on the stimulation of locomotion by peptide. The presence of ionophores (1 microM) plus external calcium inhibited locomotion.

Inhibition of Human Polymorphonuclear Leukocyte Cell Responses by Ibuprofen

The stimulation of cell swelling, cell aggregation, polymorphonuclear leukocyte locomotion, and lysosomal enzyme release in response to chemoattractant were all inhibited by ibuprofen, a nonsteroidal anti-inflammatory agent. The dosages needed to induce 50% inhibition (ID50) were 5.9, 7.6, 60, and 95 μg/mL, respectively. Aside from the differences in ID50, there was also a difference in the degree of maximum inhibition (Imax) of the complement C5a-stimulated responses observed, so that at achievable serum drug concentrations of 20-50 μg/mL, inhibition of 67-78% for cell swelling, 69-82% for cell aggregation, 20-35% for migration response, and 17-38% for lysosomal enzyme release were demonstrated. Also observed were a minor stimulatory effect on nitroblue tetrazolium reduction and an inhibitory effect on the ability to kill Staphylococcus aureus, but only at very high concentrations (∼2 mg/mL).

Effect of dimethyl sulfoxide on chemotaxis of phagocytic cells.

Abstract : Dimethyl sulfoxide (DMSO) has been highly publicized as an anti-inflammatory agent but its mechanism of action remains unknown. We hypothesized that DMSO acts by inhibiting influx of phagocytic cells to sites of inflammation and tested this premise by examining the effect of DMSO on the locomotion of polymorphonuclear leukocytes (PMN) and monocytes (MN) in vivo and in vitro. In the present study, we found that DMSO inhibits influx of PMN and MN into infected pleural spaces and decreases locomotion of PMN and MN in vitro.

Locomotion and adhesion of polymorphonuclear leukocytes effects of the supporting substratum

Contact angle measurements have been used to correlate surface hydrophobicity of a supporting substratum with adhesion and locomotion of polymorphonuclear leukocytes. The binding of human serum albumin, a well-known chemokinetic substance, to hydrophilic glass slides gave rise to hydrophobic surfaces with adhesive properties conductive to cell polarization, thus allowing cell locomotion. Parallel contact angle and cell adhesion measurements suggested that albumin modified the cell-substratum interaction by increasing the van der Waals forces of attraction and reducing the electrostatic forces. By allowing cells to adhere to a hydrophobic surface (siliconized glass), it was found that protein could be omitted from in vitro test systems for leukocyte locomotion. It is suggested that quantitatively equal cell adhesion values may, depending on the type of attraction forces working in adhesion to the substratum, result in different locomotion patterns.

Recurrent infections and delayed separation of the umbilical cord in an infant with abnormal phagocytic cell locomotion and oxidative response during particle phagocytosis

An 18-month-old infant with delayed separation of the umbilical cord and severe recurrent bacterial infections since the newborn period was found to have depressed polymorphonuclear leukocyte locomotion and oxidative metabolic response to particulate stimuli. Both her polymorphonuclear leukocytes and monocytes demonstrated a markedly delayed chemiluminescence response to zymosan, but there was a normal chemiluminescence response to soluble stimuli, phorbol myristate acetate and calcium ionophore A23187. The patient also had a marked delay in uptake of Staphylococcus aureus and Escherichia coli. The patient's polymorphonuclear leukocytes were normal morphologically, and myeloperoxidase was present in histochemical stains. The dichotomy between normal oxidative response to soluble stimuli and abnormal response to opsonized particulate stimuli, plus abnormal cell locomotion and phagocytosis, suggest an abnormality of cell membrane fluidity or contractility.

Modulation of polymorphonuclear leukocyte locomotion by synthetic amphiphiles: effect of saturated fatty acid esters (C2-C18) of poly(ethyleneglycol) 6000.

The capacity of synthetic amphiphiles poly(ethyleneglycol) 6000 (PEG) esterified with saturated fatty acids (C2-C18), to modify polymorphonuclear leukocyte (PMNL) locomotion has been investigated. It was noticed that PEG-myristate (M-PEG; C14) stimulated the random locomotion of PMNL populations in concentrations up to about 1 g/L. The esters with shorter aliphatic chains had negligible effects, whereas those with longer chains, PEG-palmitate (P-PEG; C16) and PEG-stearate (S-PEG; C18) reduced the locomotion, irrespectively of concentration. The ability of the PMNL to be stimulated by an attractant liberated from normal human serum was slightly impaired by M-PEG, but not by P-PEG. The response to M-PEG of individual PMNL was heterogeneous in that some cells were stimulated and others were inhibited. However, the average result was a reduction of the motility. This indicates that methods used for the study of the locomotion of cell populations may not always reflect the average behavior of the whole population. It was also concluded that the different effects of M-PEG and P-PEG owed to dissimilar effects on the membrane structure of the PMNL since (1) M-PEG perturbated the PMNL membrane more than P-PEG, as assayed by the release of superoxide anion (O2-), although the binding was smaller, and (2) M-PEG and P-PEG increased and decreased the membrane fluidity, respectively, as measured with fluorescent bleaching and recovery after bleaching of labeled PMNL. The results indicate a subtle coupling between membrane structure and PMNL locomotion.

Chemotaxis in yersinia arthritis. HLA-B27 positive neutrophils show high stimulated motility in vitro.

Chemotaxis, chemokinesis, and spontaneous locomotion of polymorphonuclear leukocytes (PMNs) of yersinia arthritis (YA) patients and healthy subjects with or without HLA-B27 were studied by agarose assay and membrane filter technique. HLA-B27 positive healthy control subjects and yersinia patients showed significantly higher response to chemotactic stimulus than HLA-B27 negative controls. Consequently, the high response was associated with HLA-B27 irrespective of YA. The high responder PMNs may contribute to the more severe inflammatory symptoms in YA patients with HLA-B27.

Modulation of the locomotion of polymorphonuclear leukocytes by a synthetic amphiphile, poly(ethyleneglycol) palmitate

To mimic in vitro the effect of biologically active amphipathic molecules on the locomotion of polymorphonuclear leukocytes (PMNL), the interaction and the consequences of the interaction between poly(ethyleneglycol) (PEG) esterified with palmitic acid (P-PEG) and PMNL, was studied. It was shown that P-PEG was more liable to hydrophobic interaction than PEG, and that P-PEG associated to a greater extent than PEG with PMNL. This association was inhibited by decreasing the interaction temperature from 37 to 4 °C, but it was insensitive to inhibitors of glycolysis. P-PEG decreased colchicine-facilitated capping by concanavalin A (ConA). P-PEG also decreased random locomotion of individual as well as population of PMNL. Neither cell viability nor the ability to respond by stimulated locomotion to an attractant was affected. The results indicate that P-PEG modulates PMNL locomotion by altering the membrane structure, e.g. by decreasing the lateral mobility of membrane constituents.

The effect of triisopropyl phosphate on the mobility of surface concanavalin a receptors and on the locomotion of polymorphonuclear leucocytes

The non-phosphorylating organophosphorus compound triisopropyl phosphate, which is known to inhibit rabbit leucocyte locomotion, can stimulate the locomotion of guinea pig leucocytes under certain conditions. Different methods of preparing guinea pig leucocyte monolayers can give preparations with different proportions of motile cells. With preparations that contain relatively slowly moving cells triisopropyl phosphate increases the number of stationary cells without significantly affecting the speed of the cells that remain motile. Most rabbit leucocytes labelled with fluorescein-labelled concanavalin A form caps within 5–10 min at 37 °C. In contrast the rate of cap formation in guinea pig leucocytes is much slower and after 20 min many cells have only random patches. Triisopropyl phosphate accelerates cap formation in guinea pig leucocytes but not in rabbit leucocytes. The local anaesthetic nupercaine inhibits cap and patch formation in rabbit and guinea pig leucocytes. Inhibition of rabbit leucocyte locomotion is induced by concanavalin A at 1 μg/ml. These results are briefly related to the known effects of triisopropyl phosphate on the isolated leucocyte plasma membrane.

A modified millipore filter method for assaying polymorphonuclear leukocyte locomotion and chemotaxis.

A modified millipore filter method for assaying polymorphonuclear leukocyte locomotion and chemotaxis.

The inhibition of locomotion of the polymorphonuclear leucocyte by organophosphorus compounds.

The effects of diisopropylphosphorofluoridate (DFP) and other organophosphorus compounds on the locomotion of rabbit polymorphonuclear leucocytes have been investigated in vitro using time-lapse cinémicrography. Both phosphorylating and non-phosphorylating compounds were observed to inhibit cell locomotion, not only increasing the proportion of stationary cells, but also decreasing the velocity of those cells whose movement continued. This inhibition of locomotion occurred over the same concentration range of organophosphorus compound which was previously found to enhance the effect of leucocidin on the leucocyte. Although the inhibitory effects of low concentrations of organophosphorus compounds were partly reversible, higher concentrations produced effects which continued to increase even after the cells had been returned to normal medium. It is suggested that the supposed effect of organophosphorus compounds on chemotaxis may actually be due to the inhibition of locomotion per se, probably through the detergent properties of these compounds rather than their properties as enzyme inhibitors.