The role of cytoplasmic microtubules in polymorphonuclea leukocyte chemotaxis. Evidence for the release hypothesis by means of time-lapse analysis of PMN movement relative to dot-like attractants

Effect of a single oral dose of doxycycline on polymorphonuclear leukocyte migration in a casein gradient

Tetracyclines, especially doxycycline, have been reported to inhibit the in vitro migration of polymorphonuclear leukocytes (PMNs). Twelve healthy probands were treated with doxycycline 200 mg. No inhibition of PMN migration in a casein gradient was demonstrated 24 h later. It is suggested that the effect of oral treatment with doxycycline on PMN chemotaxis is negligible.

Effects on bone marrow cells of oral treatment with podophyllotoxin derivatives in rheumatoid arthritis

SPG 827, a mixture of podophyllotoxin derivatives, has been thought to alleviate the symptoms of rheumatoid arthritis (RA) by arresting cell division in metaphase (i.e. resulting in an increase of the mitotic index) of rapidly proliferating cells of the immune apparatus. In contrast, the present study produced evidence that peroral SPG treatment of RA patients reduced the mitotic index of bone marrow cells, mainly in erythropoiesis. At the same time, slight megaloblastic changes appeared in the erythroblasts. These observations suggest that SPG treatment induced an interphase block in the G2 phase of the cell cycle, analogous to the cell action of the newer podophyllotoxin derivatives teniposide and etoposide. It may be that part of the clinical effect of SPG in rheumatoid arthritis is due to the described interphase-blocking activity.

Immotile cilia syndrome: reduced chemotaxis and reduced number of intramembranous particles in granulocytes

The neutrophil granulocytes of four patients with immotile cilia syndrome were investigated by means of freeze-fracture technique. Whereas most granulocytic functions (adherence, phagocytosis, killing of micro-organisms, reduction of NBT, and chemoluminescence) were in the normal range, chemotaxis of the neutrophils was clearly reduced; their plasma membrane revealed a profound reduction in the density of intramembrane particles. An interrelationship between reduced particle density and defective chemotaxis in neutrophils is assumed, but not yet proven.

Effects of colchicine, vinblastine and nocodazole on polarity, motility, chemotaxis and cAMP levels of human polymorphonuclear leukocytes

We present evidence for intrinsic polymorphonuclear leukocyte (PMN) polarity manifested in presence of microtubule-disrupting drugs. Polarization in response to colchicine correlated with the known dose-dependent effects of this drug on microtubule disassembly. The response to 10(-5) M colchicine, 10(-5) M vinblastine and 10(-6) M nocodazole was associated with stimulated motility and random locomotion. Responses elicited by microtubule-disrupting drugs differed from f-Met-Leu-Phe (fMLP)-induced polarization by functional and morphological criteria. Polarization, motility and orthokinesis responses were much weaker. Furthermore, ruffling was almost absent in PMNs polarized in response to colchicine, vinblastine or nocodazole. The response was inhibited by cytochalasin B, indicating that it is microfilament-dependent. We suggest that microtubule-disrupting drugs induce motility via structural changes in the cytoskeleton which act as signals for the motor apparatus. The intrinsic polarity manifested in the presence of microtubule-disrupting drugs could be reversed by an extracellular chemotactic gradient. Stimulated locomotion and motility in response to microtubule-disrupting drugs was only observed with initially spherical PMNs but not with initially motile cells. The findings provide an explanation for the numerous conflicting statements on the chemokinetic activities of these drugs. The role of cAMP in stimulated polarization and motility has been studied. Colchicine, vinblastine and nocodazole elicited a transient elevation of cAMP levels within 1 min of stimulation. cAMP elevation and stimulated motility were not quantitatively correlated.

Impaired motility and random migration of vital polymorphonuclears in vitro after therapy with oral aromatic retinoid in psoriasis

Vital polymorphonuclears of healthy persons and of patients with psoriasis before and after therapy with oral retinoid (Ro 10-9359) were observed in vitro under standardized conditions. In this model normal polymorphonuclears showed well-defined changes entering (A) a stage of resting and accommodation, (B) a stage of movement in loco, and finally, (C) a stage of migration. The rectilinear migration of cells was accompanied by characteristic movements of the cytoplasmic granula towards the cytocentrum. Just before the onset of migration, the cell organelles ordered themselves in a defined position within the cytoplasm. The survival time of the cells was about 48 hours, and their degeneration in vitro was reproducible. Polymorphonuclears of psoriasis patients without respiration before therapy with oral retinoid showed no changes. In contrast, the in vitro motility of polymorphonuclears of psoriasis under oral retinoid therapy showed distinct alterations: the movement of the cytoplasmic granula was strongly decelerated, and the regular arrangement of the cell organelles did not appear. The function of the cytocentrum was obviously impaired; the cells persisted longer in the resting stage and reached the movement stage later. A stage of migration failed to appear. The survival time was reduced to approximately 24 hours. These observations suggest that the oral retinoid interferes with the microtubular cell system and inhibits the directional migration of the polymorphonuclear in vitro.

The effect of a therapeutic doxycycline concentration on polymorphonuclear leukocyte migration in vitro

Tetracyclines, and especially doxycycline, have been reported to inhibit polymorphonuclear leukocyte (PMN) migration. The effect of a therapeutic doxycycline concentration (4.33 micrograms/ml) on PMN migration in vitro was tested with the leading-front technique. No significant effect could be demonstrated on PMN chemokinesis and chemotaxis. It is thus concluded that the effect of therapeutic doxycycline concentrations on PMN migration is negligible. This conclusion has a bearing upon the choice of antimicrobial therapy.

A quantitative microassay for leukocyte chemotaxis, using a microscopic slide system with complement-activating yeast particles as gradient source

A simple quantitative microassay was developed for studying polymorphonuclear leukocyte (PMNL) chemotaxis under conditions where the number of available cells is a limiting factor, e.g., pustules, neutropenia, small children and cerebrospinal fluid. PMNL suspensions are placed on glass slides to which fluorescein-labeled yeast particles have been fixed. After adherence, normal human serum is added to the slides. Owing to complement activation, a chemotactic gradient which attracts the adherent PMNL is formed around the yeast particles. The number of PMNL-associated yeast particles in the presence of normal serum is scored, and compared with cells migrating in the presence of inactivated serum or in the absence of serum. A locomotory index is calculated as the number of yeast particles associated with PMNL divided by the total number of yeast particles.

Joint fluid leukocytosis of patients with rheumatoid arthritis evidence for neutrophil and monocyte chemotaxis in vivo

The cell picture of the synovial fluid of fourteen patients with rheumatoid arthritis was studied in smears contrasted with the May-Grünwald-Giemsa stain. The cytology was dominated by neutrophils, many with signs of necrobiosis. The mononuclear cells displayed signs of proliferation and differentiation. Comparison with the immobile erythrocyte provided evidence that the accumulation of leukocytes in the synovial fluid of patients with rheumatoid arthritis was due to active leukocyte migration, presumably stimulated random movement and chemotaxis.

Joint fluid leukocytosis of patient with rheumatoid arthritis Computer analysis of possible explanative factors

The relationship between joint fluid leukocytosis and some clinical and laboratory parameters (disease duration, ESR, maximal titres of rheumatoid factor and of antinuclear factors, blood leukocytosis and sex) was studied in 27 consecutive patients with seropositive rheumatoid arthritis. The concentration of leukocytes was significantly higher in the synovial fluid than in peripheral blood. Variations of joint fluid leukocytosis could, however, not be explained by disease duration, actual ESR, maximal rheumatoid factor or antinuclear factor titres, concentration of blood leukocytes, or sex. It is suggested that a possible correlation between joint fluid leukocytosis and the listed parameters of rheumatoid arthritis may be too complex for analysis by a linear multiple regression model in samples of the present size.

The role of the MA-sensitive leukocyte chemotaxis in rheumatoid arthritis. A randomized double-blind clinical trial of griseofulvin treatment

Polymorphonuclear leukocyte (PMN) chemotaxis is thought to play an essential role in the pathogenesis of rheumatoid arthritis. PMN chemotaxis is in part sensitive to microtubule antagonists (MAs), e.g. colchicine. The antimycotic antibiotic griseofulvin inhibits the MA-sensitive PMN chemotaxis in vitro in concentrations far below those obtained in serum during antimycotic therapy. The role of the MA-sensitive chemotaxis in rheumatoid arthritis could thus be elucidated by a clinical trial of griseofulvin treatment. Griseofulvin (n = 20) was tested in a randomized double-blind study versus placebo (m = 19) during one year in patients with rheumatoid arthritis of mild-moderate activity. No beneficial effect of griseofulvin treatment was noted on clinical symptoms or laboratory parameters of rheumatoid arthritis. Moreover, the placebo-treated patients showed more improvement than the griseofulvin-treated patients. It is therefore suggested that the MA-sensitive chemotaxis plays a reparative role in the inflammatory lesions of rheumatoid arthritis.

The cytology of joint exudates in rheumatoid arthritis. Morphology and preparation techniques

The cytology of joint exudates from patients with rheumatoid arthritis was examined by preparation of air-dried smears; a procedure that involved cytocentrifugation of synovial fluids following dilution in a balanced salt solution containing albumin. This procedure provided a monolayer of homogeneously distributed exudate cells with excellent preservation of morphological details. The dominant cell type in the exudates was polymorphonuclear leukocytes, often with signs of necrobiosis. The small and medium-sized mononuclear cells were lymphocyte-like and vital-looking. The large mononuclear cells displayed signs of extensive phagocytosis, especially phagocytosis of polymorphonuclear leukocytes. It is suggested that the granulocytes of the synovial fluid are cells which have reached their function compartment, where they work and die.

Antitubulin activity of vinblastine and vincristine. Clinical implications of the radial segmentation test

The antitubulin activity of vinblastine and vincristine was compared by means of the radial segmentation test. Vinblastine was found to have antitubulin activity at least 6 times higher than that of vincristine. It is concluded that, if the differential indications for vinblastine or vincristine are balanced, it may be decisive for clinical treatment that more antitubulin activity can be administered as vinblastine than as vincristine.

Binding of protein chemotactic factors to the surfaces of neutrophil leukocytes and its modification with lipid-specific bacterial toxins

The binding to neutrophil leukoyctes of human serum albumin (HSA), which is chemokinetic for leukocytes, i.e. influences their rate of locomotion, and of alkali-denatured HSA, which is chemotactic for leukocytes, i.e. influences their direction of locomotion, was studied. Native serum albumin showed low affinity binding to the neutrophil surface. Denatured serum albumin showed saturable binding with a Ka of approximately 1-(6) litres per mole to about 10(6) binding sites per cell. Another protein chemotactic factor, alpha5-casein, gave similar binding. These results exclude that chemotactic reactions to denatured proteins are mediated in a completely non-specific manner and suggest the presence on the cell of a restricted number of defined recognition sites. Binding was reduced following treatment of the cells with either of two lipid-specific bacterial toxins, perfringolysin, the theta-toxin of Clostridium perfringens, an oxygen-labile cholesterol-specific toxin, and Staphylococcus aureus Sphingomyelinase C. Both have previously been shown to reduce chemotactic reactions and both were used at doses which did not reduce cell viability. These results suggest an important, and possiblly direct, role for membrane lipid in the binding sites for chemotactic factors. Visual analysis of the behaviour of perfringolysin-treated neutrophils showed that these cells were still capable of chemotactic locomotion. The cells appeared to be less efficient than normal in detecting chemotactic gradients only when at a distance from the gradient source, a finding which is consistent with reduced binding of the chemotactic factor to the cell surface.

The phagocytosis-associated chemotaxis of human mononuclear leucocytes from peripheral blood is not antitubulin-sensitive

Lymphoprep-isolated and glass-adherent mononuclear leucocytes (L-MNs) from the peripheral blood of healthy donors appeared to display directional locomotion towards sparsely distributed yeast cells during continuous observation in coverslip preparations and during observations by means of time-lapse filming in Rose chambers. The phagocytosis-associated L-MN chemotaxis was not inhibited by antitubulin concentrations which were antichemotactic thesis that a direct antitubulin-insensitive chemotaxis exists in L-MNs, besides the antitubulin-inhibited L-MN chemoataxis reported in a previous study.

Mononuclear leucocyte chemotaxis in Boyden chambers: inhibition by subantimitotic concentrations of antitubulins

The chemotaxis of Lymphoprep -isolated human mononuclear leucocytes (L-MNs) from peripheral blood was inhibited by subantimitotic concentrations of the antitubulins demecolcine, podophyllic acid ethylhydrazide, vinblastine and griseofulvin. It is suggest that L-MN chemotaxis, like polymorphonuclear leucocyte (PMN) chemotaxis, is composed of a direct antitubulin-insensitive chemotaxis and a leukocyte-induced antitubulin-sensitive chemotaxis.

In-vivo effects of anti-inflammatory and other drugs on granulocyte emigration in the rabbit skin collection chamber

A method for measuring localised leukocyte mobilisation under in-vivo conditions with a plastic skin collection-chamber adapted to the rabbit ear was used for assessing the effects of anti-inflammatory and other agents on granulocyte emigration. Studies on the effect of oral drug administration to rabbits indicated that most anti-inflammatory drugs, two cystostatic agents (cyclophosphamide and colchicine), but none of the other compounds exhibiting antihistaminc, beta-adrenolytic or neuroleptic properties, significantly inhibited granulocyte mobilisation. The results after topical application of some of these agents into the chamber correlated well with those obtained after oral treatment. This technique may thus prove useful in selecting new compounds inhibiting granulocyte mobilisation in acute inflammatory reactions.

Initiation and direction of polymorphonuclear leucocyte locomotion. The particle collision hypothesis

A simple model of the initiation of locomotion, the random movement and the directional locomotion during chemotaxis is derived from observations on moving human polymorphonuclear leucocytes (PMNs). This model provides a unifying concept of initiation of PMN locomotion, PMN random movement and PMN chemotaxis. The lamellipodium is thought to be the direction-determining cell organelle.