scholarly journals Time course of chemotaxis and chemokinesis of neutrophils following stimulation with IL-8 or FMLP

2018 ◽  
Vol 16 ◽  
pp. 205873921881917 ◽  
Author(s):  
Matthias Hattenkofer ◽  
Michael Gruber ◽  
Sophia Metz ◽  
Sophie-Marie Pfaehler ◽  
Karla Lehle ◽  
...  

Polymorphonuclear cells (PMNs) attend to inflammatory sites by chemotactic movement, caused by chemoattractants (CAs) like n-formyl-l-methionyl-l-leucyl-l-phenylalanine (FMLP) and interleukin-8 (IL-8). However, distinct but applicable assays for investigations of PMNs’ migration limit in vitro examination. We integrated CD15-bead-based isolation of PMNs with analysing their chemotaxis in a novel 3D-µ-Slide migration chamber. The PMNs were exposed to different concentrations of FMLP and IL-8 (1, 10 and 100 nM) and observed for 180 min in cell-physiological environment conditions. Moving PMNs’ percentage (median and interquartile range) decreased from 62% (27%) to 36% (31%) without CA, from 88% (30%) to 22% (26%) for 1 nM IL-8, from 70% (22%) to 28% (13%) for 100 nM IL-8, from 30% (23%) to 18% (46%) for 1 nM FMLP and from 76% (20%) to 28% (13%) for 100 nM FMLP. Centres of cell movement turned towards the CAs (negative values) within a single 30-min observation period: 5.37 µm (16.82 µm) without CA, −181.37 µm (132.18 µm) with 10 nM and −239.34 µm (152.19 µm) with 100 nM IL-8; −116.2 µm (69.07 µm) with 10 nM and −71.59 µm (98.58 µm) with 100 nM FMLP. FMLP and IL-8 ensure chemotaxis without increase of chemokinesis. 3D-µ-Slide chemotaxis chambers facilitate time course analyses of PMNs’ migration in stable conditions over a long time with concise distinction of chemotaxis and chemokinesis.

Blood ◽  
1998 ◽  
Vol 91 (9) ◽  
pp. 3439-3446 ◽  
Author(s):  
Christelle Marie ◽  
Jane Muret ◽  
Catherine Fitting ◽  
Marie-Reine Losser ◽  
Didier Payen ◽  
...  

AbstractEx vivo cytokine production by circulating lymphocytes and monocytes is reduced in patients with infectious or noninfectious systemic inflammatory response syndrome. Very few studies have addressed the reactivity of polymorphonuclear cells (PMN). To analyze further the relative contribution of systemic inflammatory response syndrome alone or in combination with infection we studied the interleukin-8 (IL-8) production by PMN isolated from patients who had undergone cardiac surgery with cardiopulmonary bypass (CPB) and patients with sepsis. Cells were activated with either lipopolysaccharide (LPS) or heat-killed streptococci. Compared with healthy controls, the release of IL-8 by PMN in both groups of patients was significantly reduced whether activated by LPS, independently of its concentration and origin, or by heat-killed streptococci. These observations suggest that stressful conditions related to inflammation, independently of infection, rapidly dampened the reactivity of circulating PMN. We investigated whether the observed diminished reactivity of PMN might reflect an endotoxin tolerance phenomenon. Our in vitro experiments with PMN from healthy controls indicated that PMN could not be rendered tolerant stricto sensu. However, our data suggested that LPS-induced mediators such as IL-10 may be responsible for the observed anergy in patients.


2003 ◽  
Vol 71 (12) ◽  
pp. 6775-6783 ◽  
Author(s):  
Tamika Burns ◽  
Zhaojing Zhong ◽  
Michael Steinitz ◽  
Liise-anne Pirofski

ABSTRACT Pneumococcal capsular polysaccharide (PS) vaccines induce type-specific immunoglobulin M (IgM), IgG, and IgA. Type-specific IgG to the PS is sufficient to confer protection against the homologous serotype of the pneumococcus, but the efficacies of type-specific IgM and IgA are less well understood. We examined the in vitro activities and efficacies in mice of two human monoclonal antibodies (MAbs) to type 8 PS, NAD (IgA) and D11 (IgM). MAb-mediated opsonophagocytic killing was evaluated after coculture of type 8 pneumococci with human polymorphonuclear cells (PMNs), type-specific or control MAbs, and human complement sources. The effects of the MAbs on PMN interleukin-8 (IL-8) and IL-6 secretion were determined in supernatants from cocultures containing pneumococci and PMNs by enzyme-linked immunosorbent assay. MAb efficacy was determined in an intratracheal model of type 8 infection in mice with classical complement pathway deficiency. Both MAbs were protective in 100% of infected mice. Neither MAb promoted a significant amount of killing of type 8 pneumococci compared to its isotype control MAb. Both type-specific MAbs mediated complement-dependent modulation of PMN IL-8 secretion, with increased secretion at effector/target (E:T) ratios of 500:1 and 50:1 and reduced secretion at 1:5. Trypan blue staining revealed that PMNs cocultured with D11 were less viable at an E:T ratio of 1:5 than PMNs cocultured with the control MAb. PMN IL-6 secretion was increased by both type-specific and control MAbs. These results suggest that certain type-specific IgM and IgAs might contribute to host defense by modulation of the inflammatory response to pneumococci.


Blood ◽  
1998 ◽  
Vol 91 (9) ◽  
pp. 3439-3446 ◽  
Author(s):  
Christelle Marie ◽  
Jane Muret ◽  
Catherine Fitting ◽  
Marie-Reine Losser ◽  
Didier Payen ◽  
...  

Ex vivo cytokine production by circulating lymphocytes and monocytes is reduced in patients with infectious or noninfectious systemic inflammatory response syndrome. Very few studies have addressed the reactivity of polymorphonuclear cells (PMN). To analyze further the relative contribution of systemic inflammatory response syndrome alone or in combination with infection we studied the interleukin-8 (IL-8) production by PMN isolated from patients who had undergone cardiac surgery with cardiopulmonary bypass (CPB) and patients with sepsis. Cells were activated with either lipopolysaccharide (LPS) or heat-killed streptococci. Compared with healthy controls, the release of IL-8 by PMN in both groups of patients was significantly reduced whether activated by LPS, independently of its concentration and origin, or by heat-killed streptococci. These observations suggest that stressful conditions related to inflammation, independently of infection, rapidly dampened the reactivity of circulating PMN. We investigated whether the observed diminished reactivity of PMN might reflect an endotoxin tolerance phenomenon. Our in vitro experiments with PMN from healthy controls indicated that PMN could not be rendered tolerant stricto sensu. However, our data suggested that LPS-induced mediators such as IL-10 may be responsible for the observed anergy in patients.


2002 ◽  
Vol 83 (6) ◽  
pp. 1505-1510 ◽  
Author(s):  
György Szittya ◽  
Dániel Silhavy ◽  
Tamás Dalmay ◽  
József Burgyán

Co-inoculation of Nicotiana benthamiana plants with in vitro transcripts of both genomic and short defective interfering (DI) RNAs of Cymbidium ringspot virus results in an accumulation of de novo generated DI RNA dimers. Time-course analysis of DI RNA accumulation in the inoculated leaves showed early accumulation of DI RNA dimers followed by increased levels of DI RNA monomers. In contrast, DI RNA dimers were barely detectable in systems where cell-to-cell movement does not take place (protoplasts) or is less important (monomeric DI RNA-expressing transgenic plants). Our results also demonstrated that the size of DI RNAs is important in the colonization of inoculated leaves, suggesting that DI RNA dimers are quickly selected for cell-to-cell movement if short DI RNA monomers are used for infection.


1991 ◽  
Vol 260 (4) ◽  
pp. C756-C762 ◽  
Author(s):  
E. Page ◽  
J. Upshaw-Earley ◽  
G. E. Goings ◽  
D. A. Hanck

An in vitro noncontracting rat atrial preparation stretched at 37 degrees C by a distending pressure of 5.1 mmHg was used to examine effects of external Ca2+ concentration ([Ca2+]out, 0.05-3.0 mM) on secretion of immunoreactive atrial natriuretic peptide (ANP) in presence of saxitoxin (STX) and in presence or absence of ryanodine. Under these conditions, the time course of the amount (y) of ANP secreted per milligram dry atrium during 44 min could be approximated by a rate coefficient (k) according to the relation y = s[1 - e(-kt)], where s is the maximal amount secreted after a long time (t). Although k, the rate coefficient for stretch-augmented secretion, increased significantly as [Ca2+]out was raised, secretion inactivated progressively in a time- and [Ca2+]out-dependent manner. This time-dependent decrease was not prevented by ryanodine. We conclude that a component of ANP secreted by quiescent atria in vitro is positively modulated by [Ca2+]out and does not require ryanodine-sensitive Ca2+ release from sarcoplasmic reticulum. The [Ca2+]out-sensitive processes underlying time-dependent inactivation of secretion remain undetermined.


2008 ◽  
Vol 104 (1) ◽  
pp. 157-169 ◽  
Author(s):  
Athanasius F. M. Marée ◽  
Mitsuhiro Komba ◽  
Diane T. Finegood ◽  
Leah Edelstein-Keshet

Macrophages play an important role in clearing apoptotic debris from tissue. Defective or reduced clearance, seen, for instance, in non-obese diabetic (NOD) mice, has been correlated with initiation of autoimmune (Type 1) diabetes (T1D) (O'Brien BA, Huang Y, Geng X, Dutz JP, Finegood DT. Diabetes 51: 2481–2488, 2002). To validate such a link, it is essential to quantify the reduced clearance (for example, by comparison to BALB/c control mice) and to determine which elements of that clearance are impaired. Recently, we fit data for the time course of in vitro macrophage feeding experiments to basic models of macrophage clearance dynamics, thus quantifying kinetics of uptake and digestion of apoptotic cells in both mouse strains (Marée AFM, Komba M, Dyck C, Łabeçki M, Finegood DT, Edelstein-Keshet L. J Theor Biol 233: 533–551, 2005). In the cycle of modeling and experimental investigation, we identified the importance of 1) measuring short-, intermediate-, and long-time data (to increase the accuracy of parameter fits), and 2) designing experiments with distinct observable regimes, including engulfment-only and digestion-only phases. Here, we report on new results from experiments so designed. In comparing macrophages from the two strains, we find that NOD macrophage engulfment of apoptotic cells is 5.5 times slower than BALB/c controls. Significantly, our new data demonstrate that digestion is at least two times slower in NOD, in contrast with previous conclusions. Moreover, new data enable us to detect an acceleration in engulfment (after the first engulfment) in both strains, but much smaller in NOD macrophages.


1987 ◽  
Author(s):  
D C Rijken ◽  
E Seifried ◽  
M M Barrett-Bergshoeff ◽  
C Kluft

It is known that plasminogen activation in blood samples taken during thrombolytic therapy with tissue-type plasminogen activator (t-PA) may continue during plasma handling, leading to artificially low fibrinogen (Fbg) and α2-antiplasmin (AP) values. Addition of D-Phe-Pro-Arg-CH2Cl or quenching antibodies against t-PA prevents this phenomenon, but these additions do not allow measurement of t-PA activity. The question of this study is, why the in vitro effects occur, even during freezing of the samples. Normal plasma was supplemented with various amounts of two-chain melanoma or recombinant t-PA and stored at -20°C, with and without a prior snap-freeze procedure. AP consumption (chromo-genic substrate assay) and Fbg degradation (Clauss method), measured in thawed samples, were most pronounced in the non snap-frozen samples. As it took a relatively long time before these samples were really frozen, the time course of the effects was studied at different temperatures. Plasma samples containing 1000 IU t-PA per ml were incubated at 37, 25,10, 0 and -8°C between 0 and 120 min. AP reduction was most rapid at 37°C (50% after 13 min), was less at 25°C (50% after 30 min), but did not further decrease at lower temperatures. The AP reduction at temperatures between 25 and -8°C corresponded to the effect of 40% t-PA activity at 37°C. The Fbg values gave a similar picture: the most rapid reduction occurred at 37°C, a slower reduction at 25°C, but no further reduction (even a small increase) was found from 25 to -8°C. The experiments were repeated in a purified system, consisting of t-PA, plasminogen, Fbg and AP. In contrast to the plasma system, AP reduction gradually decreased from 37 to 0°C. The apparent t-PA activity at 0°C was 6% of the activity at 37 °C.It is concluded that the in vitro effects in plasma samples containing t-PA can be, at least partially, explained by an abnormally strong plasminogen activation around 0°C. A normal temperature dependency in the purified system strongly suggests that unknown plasma factors enhance plasminogen activation at low temperatures.


Author(s):  
J. P. Revel

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.


1991 ◽  
Vol 66 (05) ◽  
pp. 609-613 ◽  
Author(s):  
I R MacGregor ◽  
J M Ferguson ◽  
L F McLaughlin ◽  
T Burnouf ◽  
C V Prowse

SummaryA non-stasis canine model of thrombogenicity has been used to evaluate batches of high purity factor IX concentrates from 4 manufacturers and a conventional prothrombin complex concentrate (PCC). Platelets, activated partial thromboplastin time (APTT), fibrinogen, fibrin(ogen) degradation products and fibrinopeptide A (FPA) were monitored before and after infusion of concentrate. Changes in FPA were found to be the most sensitive and reproducible indicator of thrombogenicity after infusion of batches of the PCC at doses of between 60 and 180 IU/kg, with a dose related delayed increase in FPA occurring. Total FPA generated after 100-120 IU/kg of 3 batches of PCC over the 3 h time course was 9-12 times that generated after albumin infusion. In contrast the amounts of FPA generated after 200 IU/kg of the 4 high purity factor IX products were in all cases similar to albumin infusion. It was noted that some batches of high purity concentrates had short NAPTTs indicating that current in vitro tests for potential thrombogenicity may be misleading in predicting the effects of these concentrates in vivo.


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