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An in vitro model for analysing neutrophil migration into and away from the sub-endothelial space: Roles of flow and CD31.

To model the later stages of neutrophil migration into tissue, we developed an assay in which human umbilical vein endothelial cells (HUVEC) were cultured on porous filters, treated with the inflammatory cytokine tumour necrosis factor-alpha (TNF), and then incorporated in a flow chamber. Video-microscopic observations were made of neutrophils as they were perfused over the HUVEC. When 3 microm pore filters were used (as opposed to 0.4 microm pore filters), neutrophils could be observed to migrate not only through the endothelial monolayer but also through the filter within minutes. The proportion of adherent neutrophils migrating through the endothelial monolayer and velocity of migration underneath it, were similar on the different filters, and also when neutrophils were perfused over cultures in glass capillaries, or settled on HUVEC cultured in standard plastic dishes. However, neutrophils migrated through HUVEC/filter constructs more rapidly in the flow chamber than in a standard, static, Transwell system, even though the velocities of migration under HUVEC were similar when directly observed under flow or static conditions. A function-blocking antibody against CD31 did not alter movement through the endothelial monolayer or the filter in the new flow system, but did reduce the migration velocity of neutrophils underneath the HUVEC (by 24%). Thus, we have developed a method for following each stage of neutrophil migration, including exit from the sub-endothelial space, and shown how they may be modified by applied fluid shear stress and blockade of a regulatory adhesion molecule.

Cell Adhesion↗

Differential utilization of ICAM-1 and VCAM-1 during the adhesion and transendothelial migration of human T lymphocytes.

The comparative roles of the endothelial cell (EC) adhesion receptors VCAM-1 and ICAM-1 during the adhesion and transendothelial migration of T cells were examined. The adhesion of T cells to IL-1-activated EC was markedly, but not completely, inhibited by mAb to VCAM-1 as well as to its counter-receptor, VLA-4, whereas, T cell binding to IL-1-activated EC was not blocked by mAb to ICAM-1 or to its counter-receptor, LFA-1. In contrast, LFA-1/ICAM-1, but not VLA-4/VCAM-1, mediated much, but not all, of the binding of T cells to unstimulated EC. Activation of T cells with phorbol dibutyrate and ionomycin alter the receptor-counter-receptor pairs used for binding to EC. Regardless of the activation status of the EC, the binding of activated T cells was not blocked by mAb to VLA-4 or VCAM-1. Moreover, the binding of activated T cells to EC was blocked to a lesser degree by mAb to LFA-1 than that of resting T cells, and mAb to ICAM-1 blocked binding only modestly. The role of VCAM-1 and ICAM-1 during the transendothelial migration of T cells was also examined. Regardless of the activation status of the T cells or the EC, VCAM-1 was never found to function during transendothelial migration, even when it mediated the binding of resting T cells to IL-1-activated EC. In contrast, ICAM-1 played an important role in transendothelial migration under all of the conditions examined, including situations when T cell-EC binding was not mediated by ICAM-1. Immunoelectron microscopic analysis of transendothelial migration supported the conclusion that ICAM-1 but not VCAM-1 played a central role in this process. Thus, ICAM-1 was prominently and uniformly expressed at all EC membrane sites that were in contact with bound and migrating T cells, whereas VCAM-1 was localized to the luminal surface of IL-1-activated EC, but was often absent from the surface of the EC in contact with T cells undergoing transendothelial migration. These studies confirm that ICAM-1 and VCAM-1 play reciprocal roles in the binding of resting T cells to resting and IL-1-activated EC, respectively, but a less prominent role in the binding of activated T cells. Moreover, ICAM-1 but not VCAM-1 plays a role in transendothelial migration, regardless of the receptor-counter-receptor pairs used for initial binding.

Cell Adhesion↗

Distal humeral migration as a component of multidirectional shoulder instability. An anatomical study in autopsy specimens.

The object of the present study of autopsy specimens was to evaluate distal humeral migration during abduction allowed by sequential severance of capsular and ligamentous structures stabilizing the shoulder joint. A kinesiologic testing device continuously registered distal humeral migration, abduction angle, rotation, and flexion-extension. No distally directed force was applied to the humerus except the weight of the apparatus. Significant distal migration was recorded in the entire range of abduction (0 degrees -60 degrees) after solitary severance of the coracohumeral ligament as well as the proximal part of the anterior joint capsule. Further sectioning of the proximal part of the posterior capsule did not significantly increase distal humeral migration. Maximum distal migration (25 mm) was measured at 20 degrees of abduction. Applying an internal torque to the humerus significantly prevented distal migration as long as the posterior capsule was kept intact. Clinical testing for distal humeral migration should be performed with the shoulder joint at 20 degrees of abduction and neutral rotation. Furthermore, distal humeral migration can be significantly reduced by internal rotation of the humerus when the posterior joint capsule is intact.

Aged↗

Neutral glycolipids of migrating and nonmigrating rabbit corneal epithelium in organ and cell culture.

It is generally believed that plasma membrane glycoconjugates influence corneal epithelial cell migration after wounding. Previous studies have focused on the role of glycoproteins in this event. The present study was designed to determine whether migration-specific glycolipids are synthesized by epithelium of healing rabbit corneas. Migrating and nonmigrating rabbit corneal epithelia were incubated with [3H]-galactose in an organ culture system for 48 hr. At the end of the labeling period, a neutral glycosphingolipid (NGSL) fraction was isolated from each radiolabeled epithelium and was analyzed by thin-layer chromatography. Three radiolabeled NGSL components, M1, M2 and M3 (M1-M3), were present in significantly higher amounts in the extracts of migrating as compared to nonmigrating epithelium. Chromatographic mobility of M3 was similar to that of a standard glucosylceramide; M1 and M2 migrated more slowly than M3. For characterization of the migration-related NGSL, a large amount of the starting material is required. Experiments, therefore, were conducted using cell cultures of rabbit corneal epithelium. Confluent (nonmigrating) cell cultures of rabbit corneal epithelium were found to synthesize either minimal or undetectable amounts of NGSL M1-M3. In contrast, we found that the NGSL M1-M3 are synthesized as major components by sparse (migrating) corneal epithelial cell cultures. Components M1-M3 were synthesized as major components by sparse cultures even in the absence of cell mitosis. This suggests that the increased synthesis of components M1-M3 by sparse cell cultures may be related to cell migration rather than cell mitosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Effect of prostaglandin E2-producing nonmetastatic Lewis lung carcinoma cells on the migration of prostaglandin E2-responsive metastatic Lewis lung carcinoma cells.

The role of prostaglandin E2 (PGE2) in directly stimulating metastatic spread by Lewis lung carcinoma (LLC) cells was examined with the use of an in vitro migration model for tumor dissemination. The extent to which cloned metastatic and nonmetastatic LLC cells migrated out of glass capillary tubes in vitro reflected their capacity to form pulmonary metastases in vivo. The addition of PGE2 to metastatic LLC cells further stimulated their migration. Other cyclooxygenase products, besides PGE2, did not stimulate the migration of metastatic LLC cells. Nonmetastatic LLC cells did not migrate out of capillary tubes, even in the presence of exogenous PGE2. The amount of PGE2 secreted by cloned LLC cells was quantitated by a radioimmunoassay. Nonmetastatic LLC cells secreted more PGE2 than did the metastatic LLC cells. When the nonmetastatic LLC cells were either mixed with or placed adjacent to cloned metastatic LLC cells, the migration by the metastatic LLC cells was stimulated. The migration-stimulatory capacity of the nonmetastatic LLC cells was minimized in the presence of indomethacin, a prostaglandin synthesis inhibitor. Studies were conducted to relate these in vitro results to tumor metastasis in vivo. Injection of a mixture of metastatic and nonmetastatic LLC cells into mice s.c. resulted in a greater number of lung metastases than did injection of metastatic cells alone. This increase in metastasis formation was prevented by indomethacin. Formation of pulmonary metastases was also augmented when irradiated nonmetastatic LLC cells were injected into metastatic LLC-bearing mice. The results of our studies suggest that nonmetastatic LLC cells, by producing PGE2, can augment in vitro migration and in vivo dissemination of metastatic LLC cells. Thus, the response of tumor cells to PGE2, rather than simply their production of PGE2, appears to be important in regulating tumor dissemination.

16,16-Dimethylprostaglandin E2↗

The migration of hematopoietic cells: an in vitro study system.

An in vitro migration assay system for the study of hematopoietic cell migration was established. Using a large well modification of earlier described migration chambers, it was found that, in the presence of whole murine serum from either normal or aplastic mice, a heterogeneous population of cells was stimulated to migrate through limited size pores (8 mu) in a thin (5 mu) polycarbonate filter. In dilution studies, serum obtained from animals that had been rendered aplastic by total body irradiation provided a stronger migration stimulus than serum from normal animals. This observation is consistent with observations of hematopoietic cell migration in vivo. Primitive spleen colony-forming cells and in vitro granulocyte/macrophage colony-forming cells were present in the migrating population at a comparable fraction to that found in untreated bone marrow. These studies demonstrate the feasibility of studying hematopoietic stem cell migration under controlled experimental conditions.

Animals↗

Glial-guided granule neuron migration in vitro: a high-resolution time-lapse video microscopic study.

To study neuronal migration, migrating granule neurons in microcultures prepared from early postnatal cerebellum have been analyzed with time-lapse, video-enhanced differential interference contrast microscopy. The morphology of migrating neurons resembles the elongated forms of migrating neurons described both in vivo and in vitro (Rakic, 1971; Hatten et al., 1984). The neuron closely apposes its soma along the glial fiber and extends a thickened leading process in the direction of migration. This leading tip is highly motile, with several filopodial extensions. Intracellular vesicular structures extend from the nucleus into the leading process of migrating neurons in vitro. Quantitation of the motions of migrating neurons revealed a saltatory pattern of advance along the glial fiber. Periods of cell soma movement at the rate of 56 +/- 26 micron/hr along the glial fiber are punctuated by periods during which the cell soma slows to a complete stop. The overall rate of migration is 33 +/- 20 micron/hr. The growing tip of the leading process rapidly extends and retracts, resulting in a net advance along the glial fiber. However, the periods of the extension and retraction of the leading process growing tip are not synchronized with the motions of the cell soma.

Animals↗

Influence of ethanol on human T-lymphocyte migration.

Because ethanol consumption is associated with increased susceptibility to infection, we examined the effects of ethanol and its metabolite acetaldehyde on human T-lymphocyte migration, an important functional component of cellular inflammatory responses. With a modified Boyden chamber system, ethanol at 0.25% and 0.50% (vol/vol) inhibited spontaneous motility of human T-lymphocytes, in a noncytotoxic manner, to 65% +/- 7% (mean +/- SEM) and 62% +/- 7% of control values of migration, respectively. When T-lymphocyte migration was stimulated by colchicine (10(-5) mol/L), incubation with ethanol (0.25% and 0.50%, vol/vol) decreased migration to 80% +/- 4% and 66% +/- 8% of control values, respectively. Similar degrees of inhibition of migration were obtained with acetaldehyde at concentrations five to 10 times less than ethanol. Ethanol was similarly capable of inhibiting T cell migration induced by dibutyryl cyclic guanosine monophosphate, but it had no effect on stimulated migration induced by a human chemokinetic lymphokine. Our study demonstrates that ethanol, at concentrations achievable in vivo, is capable of depressing T-lymphocyte migration. This effect might contribute to the immunosuppression associated with ethanol consumption.

Acetaldehyde↗

Spontaneous capillary tube migration of metastatic rat mammary adenocarcinoma cells.

The spontaneous capillary tube migration of metastatic MAT 13762 rat mammary adenocarcinoma cells has been measured and compared with that of a non-metastatic variant, TGR. MAT 13762 cells migrated to a greater extent in the presence than in the absence of serum, and in both cases migration areas were considerably greater than for TGR cells. Different clones of hybrids, formed by fusing metastatic and non-metastatic variants, showed migration areas ranging from those of the metastatic to those of the non-metastatic parent cells. Despite their differing migrations, all of these clones were either non or only slightly metastatic. Treatment of TGR cells with trypsin enhanced their migration to that of MAT 13762 cells, whereas trypsin-treated MAT 13762 cells showed a slightly decreased migration. Although MAT 13762 cells, unlike TGR cells, produced large amounts of plasminogen activator (PA), no evidence was obtained for the direct involvement of PA in the high migration rate of MAT 13762 cells.

Adenocarcinoma↗

The migration and survival of gamma-irradiated Schistosoma mansoni larvae and the duration of host-parasite contact in relation to the induction of resistance in mice.

The migration in mice of 20, 50 and 90 krad. 60Co-irradiated Schistosoma mansoni larvae, biosynthetically radio-isotope labelled with [75Se]-selenomethionine, was evaluated by autoradiography of compressed tissues and compared to the migration of non-irradiated 75Se-labelled larvae. The migration of 20 krad.-irradiated schistosomula between skin and lungs was slightly delayed but otherwise paralleled the migration of normal, non-irradiated schistosomula during the first 8 days following exposure. By day 8 over 90% of both non-irradiated and 20 krad.-irradiated organisms were located in the lungs. In contrast to non-irradiated organisms, however, only a small proportion of 20 krad. organisms migrated to the liver. The delay in migration between skin and lungs was more pronounced with 50 krad.-irradiated schistosomula. Nevertheless, 45-93% of 50 krad.-irradiated organisms migrated to the lungs by 8 days post-exposure. Over 90% of the 50 krad. larvae detected in the mouse on day 21 were in the lungs; no more than an occasional 50 krad.-irradiated organism was ever detected in the liver. In three experiments, over 85% of the 90 krad.-irradiated organisms were retained in the skin; in a fourth experiment about half of the 90 krad.-irradiated organisms migrated as far as the lungs. As with 50 krad. organisms, only an occasional 90 krad. organism was ever detected in the liver. Removal of the skin exposure site within the first 4 days of immunization with either 50 or 90 krad.-irradiated cercariae completely blocked the induction of resistance. Removal between the 4th and 6th days gave variable results. Mice had to be in contact with the irradiated larvae for a minimum of 8-11 days to stimulate a level of resistance comparable to that of mice whose immunization site was not removed.

Animals↗

A role for endogenous mono-hydroxy-eicosatetraenoic acids (HETEs) in the regulation of human neutrophil migration.

The possibility that endogenous monohydroxy-eicosatetraenoic acids (HETEs) derived from the lipoxygenation of arachidonic acid might serve a role in human neutrophil migration was examined by studying the effects of depletion of the intracellular HETEs on random migration and chemotaxis. The intracellular contents of approximately 2000 ng of 11-HETE and 500 ng of 5-HETE per 10(8) neutrophils are distributed preferentially in the cellular membranes and are increased by specific chemotactic factors. The depletion of intracellular HETEs that resulted from pre-incubating, washing and resuspending neutrophils in 3-20 microM 5,8,11,14-eicosatetraynoic acid (TYA), an inhibitor of lipoxygenase and cyclooxygenase activity, or in 5-10 microM nordihydroguaiaretic acid (NDGA), a selective inhibitor of lipoxygenase activity, was associated with suppression of neutrophil random migration and chemotaxis to several stimuli without evidence of cytotoxicity. Maximal suppression of migration was achieved by a 30-60 min preincubation with the inhibitors, a time-course analogous to that required for optimal depletion of the endogenous HETEs. In contrast, inhibitors of cyclooxygenase activity enhanced random migration and, to a lesser extent, chemotaxis. The inhibition of migration achieved by pre-incubating and maintaining the neutrophils in TYA or NDGA was fully reversed either by washing and resuspending the neutrophils in buffer or by the addition of purified neutrophil 5-HETE in quantities as small as 20 ng/2 x 10(6) neutrophils for random migration and 0.8 ng/2 x 10(6) neutrophils for chemotaxis, while the addition of 11-HETE was less effective. The relationship of the intracellular concentrations of endogenous HETEs to neutrophil migration is consistent with a potential role of the HETEs as cellular mediators.

5,8,11,14-Eicosatetraynoic Acid↗

A study of leukemic cell migration by an agarose plate method.

By means of inducing random migration of leukemic cells in human peripheral blood by an agarose plate method, a study was made to see how migration distance and cell morphology after migration differed with the type of leukemia. After 3 days of incubation, the distance of random migration in cells of lymphocytic leukemia patients was on the average 0.41 mm for the cells of 13 patients with adult T-cell leukemia/lymphoma and 0.03 mm for the cells of four patients with chronic lymphocytic leukemia which were all of B-cell origin. Thus leukemic cells of T-cell origin migrated farther than those of B-cell origin. In the cases of myelocytic leukemia, the distance of random migration was on the average 0.54 mm for the cells of five patients with acute myelocytic leukemia, 2.42 mm for the cells of three patients with acute myelomonocytic leukemia, 1.69 mm for the cells of four patients with chronic myelocytic leukemia at blastic crisis and 3.78 mm for the cells of one patient with chronic monocytic leukemia. Thus, cells of monocyte origin migrated quite well. Migrating cells differing from cells of smear samples retained their original natural morphology and were considered to serve as an aid in the differentiation of types of leukemia.

Adult↗

The characterization of lymphocytes migrating through chronically inflamed tissues.

Afferent lymphatics draining Freund's adjuvant-induced granulomas and efferent lymphatics from normal subcutaneous lymph nodes were cannulated in sheep. It was previously reported that cells collected from these lymphatics, after being radiolabelled with 111In and returned to the animal intravenously, migrated from the blood back through the granuloma or lymph node into the lymph compartment from which they were originally obtained. Afferent lymph cells preferentially migrated out of the circulation in the granuloma rather than the lymph node. The cell responsible for this selective migration was found to be a small recirculating T lymphocyte. Macrophages and lymphoblasts did not demonstrate this migration. Similarly, B cells did not contribute to the lymphocyte migration observed. The migration of lymphocytes through normal uninflamed skin was examined. Afferent cells migrated through normal skin in the same way as through a granuloma, suggesting that neither antigen nor local inflammatory changes were responsible for this migration.

Animals↗

Polyacrylamide as a substitute for cervical mucus in sperm migration tests.

A synthetic migration medium for capillary sperm migration studies was developed. Parallel sperm migration in 1.8% polyacrylamide cross-linked with 0.042% N,N'-methylene bis acrylamide was similar to sperm migration in bovine cervical mucus. Bull spermatozoa varying widely in migration distances in bovine cervical mucus maintained similar relative migration distances in this synthetic medium. The advantages of the synthetic medium are its availability in large quantities, its uniformity, and its stability. There was no change in parallel sperm migration distances in the synthetic medium stored at 4 degrees C for up to 4 months. Use of this synthetic medium for human or bovine sperm migration studies would appear to overcome problems associated with the variability of cervical mucus.

Acrylamides↗

Influence of cells number on directional migration of MO4 cells in vitro.

The diameter of the circular area covered by MO4 cells explanted as a spheroid on glass is used as an index of directional migration. MO4 cells, the proliferation of which is inhibited by 5-fluorouracil or ionizing radiation can perform directional migration, indicating that directional migration and proliferation are basically unrelated cellular activities. In non-proliferating populations the distance of directional migration appears to increase with increasing volume of the original spheroid, indicating that directional migration is influenced by the cell number. Stimulation of directional migration is also obtained by explanting a second spheroid in the center of the area covered by cells from a first spheroid. Comparison of directional migration of cells from irradiated spheroids with that from spheroids in presence of 5-fluorouracil, shows that apart from the cell number, volume, degree of spread, number and type of intercellular contacts also influence directional migration.

Animals↗

A technique for the recovery of nematodes from ruminants by migration from gastro-intestinal ingesta gelled in agar: large-scale application.

A gelled-agar technique for worm recovery was adapted to facilitate the recovery of larval and adult nematodes from the total ingesta of large numbers of sheep. The technique was also used to recover nematodes from 4 calves. In one trial involving 120 sheep, 100% of 2013 4th stage larvae (L4) and 92,1% of 134,205 adult Haemonchus contortus migrated from the agar preparations. Highly significantly more male than female worms failed to migrate. Using 1 x 1/10 aliquot to estimate the numbers of worms that failed to migrate from the agar, the mean error in the total worm count (worms that migrated plus those that failed to migrate) per sheep was 2,2%; with an examination of 2 x 1/10 aliquot the error was 1,7%. We concluded from this that the gelled-agar method may be of value for quantitative worm recovery, for example, in anthelmintic tests. In a second trial, 98,5% of 17,056 L4 and adult nematodes of 5 genera migrated from the ingesta of 4 calves and 96,4% of 62,597 L4 and adult nematodes of 9 species from the ingesta of 15 sheep. In general, L4 migrated slightly more efficiently than adult worms. In sheep and, to a lesser extent, in calves, Haemonchus spp. did not migrate as efficiently as the other genera such as Ostertagia, Trichostrongylus, Nematodirus, Oesophagostomum, Marshallagia and Chabertia.

Abomasum↗

Prediction of clinical outcome of THR from migration measurements on standard radiographs. A study of cemented Charnley and Stanmore femoral stems.

We report the theoretical basis of a method to measure axial migration of femoral components of total hip replacements (THR). The use of the top of the greater trochanter and a lateral point on the collar of the stem, allowing for variations of up to 10 degrees rotation of the femur in any direction between successive radiographs, gave a maximum error of 0.37 mm. At a more realistic 5 degrees rotational variation, the error was only 0.13 mm. These data were confirmed in an experimental study using digitisation of points and special software. We also showed that the centre of the femoral head, the stem tip, and the lesser trochanter provided less accurate landmarks. In a second study we digitised a series of radiographs of 51 Charnley and 57 Stanmore THRs; the mean migration rates were found to be identical. We then studied 46 successful stems with a minimum follow-up of eight years and 46 stems which had failed by aseptic loosening at different times. At two years, the successful stems had migrated by a mean of 1.45 +/- 0.68 mm, but the failed cases had a mean migration of 4.32 +/- 2.58 mm (p < 0.0001). Of the successful cases 76% had migrated less than 2 mm, while in the failed group 84% had migrated more than 2 mm. For any particular case migration of more than 2.6 mm at two years had only a 5% chance of continuing success and would therefore merit special follow-up. Only 24% of the eventually successful stems showed migration at the stem-cement interface, but this had happened in every failed stem. We conclude that it would be possible to evaluate a new cemented design of femoral stem over a two-year period by the use of our method and to compare its performance against the reported known standard of the Charnley and Stanmore designs.

Arthritis, Rheumatoid↗

TGF-beta 2 decreases migration of lymphocytes in vitro and homing of cells into the central nervous system in vivo.

Migration of leukocytes through an in vitro, cell culture model of the blood-brain barrier (BBB) composed of murine brain microvessel endothelial (En) cells and astrocytes, and in vivo in experimental allergic encephalomyelitis (EAE), was investigated. We have recently shown that the adhesiveness of cultured murine brain microvascular endothelial cells for lymphocytes can be increased significantly by pretreatment with IL-1 beta, TNF-alpha, IFN-gamma, and LPS. In the present study, we investigated the role of TGF-beta 2 on the migration of leukocytes through the BBB. In vitro migration was assessed by measuring the percentage of 51Cr-labeled leukocytes migrating through the En/astrocyte monolayers. The basal level of migration was up-regulated significantly by treating the En/astrocyte monolayers with IL-1 alpha, IFN-gamma, TNF-alpha, and LPS. The ability of these cytokines to modulate migration was dose-dependent. Treatment of En cell/astrocyte monolayers with TGF-beta 2 down-regulated the level of leukocyte migration up-regulated by IL-1 alpha, IFN-gamma, and TNF-alpha in vitro in a dose-dependent manner. TGF-beta 2 also inhibited the migration of lymphocytes into the central nervous system (CNS) in vivo in a dose-dependent fashion. Taken together, these findings strongly suggest that TGF-beta plays an important role in the reduction of lymphocyte infiltration into the CNS in inflammatory demyelinating diseases such as EAE.

Animals↗