Effect of substratum wettability and charge on adhesion in vitro and encapsulation in vivo by insect haemocytes

1983 ◽  
Vol 63 (1) ◽  
pp. 181-190 ◽  
Author(s):  
A.M. Lackie
Keyword(s):  
Periplaneta Americana ◽  
Schistocerca Gregaria ◽  
Body Cavity ◽  
Similar Proportion ◽  
Cell Behaviour ◽  
Polystyrene Beads ◽  
Abiotic Surfaces ◽  
Insect Haemocytes

The circulating leucocytes of insects, the haemocytes, adhere to and encapsulate foreign material that enters the insect's body cavity. The thickness of the capsule depends not only on the insect species but also on the nature of the object concerned, a fact that is of great importance to invading parasites and pathogens. In this paper, some of the factors that may stimulate haemocyte adhesion and subsequent encapsulation of the object have been investigated using abiotic materials with surfaces of different charge and wettability. The negativity and wettability of surfaces of polystyrene beads and plates can be increased by pretreatment with acid, and adhesion of haemocytes to these modified surfaces has been examined in vivo and in vitro. A similar proportion of haemocytes of the locust Schistocerca gregaria adhere to the plates in vitro, irrespective of the changes in charge and wettability, but the adhesion of haemocytes of the cockroach Periplaneta americana is proportional to the increases in both parameters. These differences in cell behaviour are reflected in vivo: cockroach haemocytes form thicker capsules around more hydrophilic and more negatively charged polystyrene beads, while locust cells encapsulate both types of surface to the same, minimal, degree. Positively and negatively charged Sepharose beads are encapsulated more thickly than are neutral beads in cockroaches; negatively charged Sepharose beads are not encapsulated at all in locusts. There are thus obvious differences between the two species in the ways in which their haemocytes respond to these modified abiotic surfaces. It is suggested that capsule thickness in vivo depends on the initial cell-substratum contact; different surfaces stimulate the cell to different extents, which in turn causes variations in the recruitment of other cells to the capsule.

Surface charge of insect haemocytes, examined using cell electrophoresis and cationized ferritin-binding

1985 ◽  
Vol 75 (1) ◽  
pp. 207-214
Author(s):  
G. Takle ◽  
A.M. Lackie
Keyword(s):  
Surface Charge ◽  
Periplaneta Americana ◽  
Schistocerca Gregaria ◽  
Cationized Ferritin ◽  
Cell Electrophoresis ◽  
Insect Haemocytes ◽  
Negative Surface ◽  
Negative Surface Charge

Differences in the negative surface charge of haemocytes from Periplaneta americana and Schistocerca gregaria have been revealed using cell electrophoresis and cationized ferritin-binding. Although haemocyte populations from both insect species exhibit ranges of negative surface charge, both techniques show that Schistocerca haemocytes are significantly more negative than Periplaneta haemocytes. The results may help to explain why Schistocerca haemocytes adhere poorly to negative substrata, both in vitro and in vivo, and suggest that an electrostatic mechanism may be involved, at least in part, in adhesion of insect haemocytes to substrata.

scholarly journals An optimised GAS-pharyngeal cell biofilm model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Heema K. N. Vyas ◽  
Jason D. McArthur ◽  
Martina L. Sanderson-Smith
Keyword(s):  
Crystal Violet ◽  
Biofilm Formation ◽  
Cell Model ◽  
Matrix Material ◽  
Three Dimensional ◽  
Growth Period ◽  
Optimal Growth ◽  
Abiotic Surfaces

AbstractGroup A Streptococcus (GAS) causes 700 million infections and accounts for half a million deaths per year. Biofilm formation has been implicated in both pharyngeal and dermal GAS infections. In vitro, plate-based assays have shown that several GAS M-types form biofilms, and multiple GAS virulence factors have been linked to biofilm formation. Although the contributions of these plate-based studies have been valuable, most have failed to mimic the host environment, with many studies utilising abiotic surfaces. GAS is a human specific pathogen, and colonisation and subsequent biofilm formation is likely facilitated by distinct interactions with host tissue surfaces. As such, a host cell-GAS model has been optimised to support and grow GAS biofilms of a variety of GAS M-types. Improvements and adjustments to the crystal violet biofilm biomass assay have also been tailored to reproducibly detect delicate GAS biofilms. We propose 72 h as an optimal growth period for yielding detectable biofilm biomass. GAS biofilms formed are robust and durable, and can be reproducibly assessed via staining/washing intensive assays such as crystal violet with the aid of methanol fixation prior to staining. Lastly, SEM imaging of GAS biofilms formed by this model revealed GAS cocci chains arranged into three-dimensional aggregated structures with EPS matrix material. Taken together, we outline an efficacious GAS biofilm pharyngeal cell model that can support long-term GAS biofilm formation, with biofilms formed closely resembling those seen in vivo.

scholarly journals Periplaneta Americana Extract may Attenuate 2,4,6-Trinitrobenzenesulfonic Acid-Induced Intestinal Fibrosis by Inhibiting TGF-β/Smad Signaling Pathway

2021 ◽  
Author(s):  
Jing Liu ◽  
Pin Lv ◽  
Xiang Rao ◽  
Jiajia Wang
Keyword(s):  
Western Blot ◽  
Signaling Pathway ◽  
Real Time Pcr ◽  
Periplaneta Americana ◽  
Collagen I ◽  
Smad Signaling ◽  
Intestinal Fibrosis ◽  
Smad Signaling Pathway

Abstract PurposeIntestinal fibrosis is an incurable digestive disease accompanied by stricture formation, and it has an increasing incidence in recent years. Periplaneta americana is one of the medicinal insects with a long history. There are few reports on the effect of intestinal fibrosis. This study aims to evaluate the inhibitory effect of PA treatment on intestinal fibrosis. MethodsTNBS was used to establish intestinal fibrosis model by enema in BALB/c mice. The mice were treated with PA (50, 100, 200 mg/kg body weight) and 5-aminosalicylic acid (5-ASA) (40mg/kg) by gavage once a day for 6 weeks. At the end of the last week, the mice were sacrificed. Colon samples were collected for H&E and Masson staining. The mRNA and protein expression of α-smooth muscle actin (α-SMA), collagen I and the transforming growth factor-β (TGF-β) / Smad signaling pathway were conducted by real-time PCR and western blot analysis. In vitro, TGF-β1 was used to induce intestinal fibrosis at human colon fibroblasts (CCD-18Co). And using real-time PCR and western blot methods to detect the expression of α-SMA and collagen I. ResultsPA inhibited the expression of α-SMA and collagen I in vivo and in vitro. But the difference was that PA inhibited the TGF-β/Smad signaling pathway in vivo, and the same results had not been obtained in vitro. Conclusion: PA may attenuate intestinal fibrosis by inhibiting TGF-β/Smad signaling pathway, but more experiments were needed to prove it in vitro. ConclusionsPA has potential pharmacological effects in inhibiting intestinal fibrosis, and the TGF-β/Smad signaling pathway seemed promising.

Studies on Chitin Synthesis in the Desert Locust

1962 ◽  
Vol 39 (1) ◽  
pp. 129-140 ◽  
Author(s):  
D. J. CANDY ◽  
B. A. KILBY
Keyword(s):  
Schistocerca Gregaria ◽  
In Vivo Studies ◽  
Desert Locust ◽  
Uridine Diphosphate ◽  
In Vitro Experiments ◽  
Chitin Synthesis ◽  
Acetyl Coenzyme A ◽  
Phosphohexose Isomerase

1. In vivo studies on 5th instar and adult locusts revealed that chitin formation in thorax, abdomen, hind leg and wing was greatest during the first few days after moulting. 2. Wing extracts were used for in vitro experiments, and evidence was obtained for the presence of the following enzymes: hexokinase, phosphohexose isomerase, glutamine transaminase, phosphoglucosamine transacetylase, acetyl coenzyme-A synthetase, phosphoacetylglucosamine mutase and uridine diphosphate N-acetylglucosamine pyrophosphorylase. 3. The results are discussed, and a tentative scheme is presented for the biosynthesis of chitin in the wing of Schistocerca gregaria.

Studies on Tapeworm Physiology

1946 ◽  
Vol 23 (1) ◽  
pp. 47-70 ◽  
Author(s):  
J. D. SMYTH
Keyword(s):  
Histological Examination ◽  
Gasterosteus Aculeatus ◽  
Body Cavity ◽  
Final Host ◽  
The Body ◽  
Normal Behaviour ◽  
The Mean ◽  
Peptone Broth

A technique has been elaborated that enabled the plerocercoid larvae of Schistocephalus solidus to be removed from the body cavity of Gasterosteus aculeatus without bacterial contamination. Larvae were cultured in plugged test-tubes under completely aseptic conditions in a variety of balanced salines, glucose salines and nutrient peptone broth. The most successful results were obtained with peptone broth at room temperatures (16-19° C) in which plerocercoids remained active and showed normal behaviour for periods up to 300 days. In ¾ strength Locke's solution, which was found by experiment to be approximately isotonic with Schistocephalus (δ = -0.44 ± 0.02° C), the mean period of normal behaviour was 114 days. In the remaining saline and saline-glucose media, the mean viability and period of normal behaviour was considerably less. In the plerocercoid, histological examination revealed that the genitalia are in an immature condition. During cultivation at room temperatures, the genitalia remained in this undifferentiated condition and showed no signs of undergoing spermatogenesis, oogenesis or vitellogenesis. Plerocercoids were induced to develop into sexually mature adults by raising the temperature of cultivation in peptone broth to 40° C. (i.e. the body temperature of the final host in the natural life cycle). Oviposition took place after 48-60 hr. at this temperature, and histological examination revealed that spermatogenesis, oogenesis, vitellogenesis and shell formation had taken place in a normal manner. The viability of artificially matured Schistocephalus was 4-6 days in vitro--a period equivalent to the viability of the adult in vivo. The eversion of the cirris was observed in each proglottid after 40 hr. cultivation at 40° C. During the sexual process the cirris everted and invaginated at the rate of about once per second. Cross-fertilization between segments of the same worm or with segments of another worm was not observed. Except for one specimen in ¾ strength Locke's solution which underwent spermatogenesis and partial vitellogenesis, larvae cultured in salines or glucose salines at 40° C. died within 1-3 days without further development. Attempts to hatch out the eggs produced by the cultivation of larvae in peptone broth at 40° C. proved unsuccessful. Histological examination revealed that spermatozoa had not been taken into the vagina. It was concluded that the eggs were not fertilized owing to the failure of normal copulation to take place.

scholarly journals Natural Architectures for Tissue Engineering and Regenerative Medicine

2020 ◽  
Vol 11 (3) ◽  
pp. 47
Author(s):  
Floris Honig ◽  
Steven Vermeulen ◽  
Amir A. Zadpoor ◽  
Jan de Boer ◽  
Lidy E. Fratila-Apachitei
Keyword(s):  
Tissue Engineering ◽  
Regenerative Medicine ◽  
Surface Properties ◽  
State Of The Art ◽  
Cell Behaviour ◽  
Cell Responses ◽  
Underlying Mechanisms ◽  
Functional Biomaterials

The ability to control the interactions between functional biomaterials and biological systems is of great importance for tissue engineering and regenerative medicine. However, the underlying mechanisms defining the interplay between biomaterial properties and the human body are complex. Therefore, a key challenge is to design biomaterials that mimic the in vivo microenvironment. Over millions of years, nature has produced a wide variety of biological materials optimised for distinct functions, ranging from the extracellular matrix (ECM) for structural and biochemical support of cells to the holy lotus with special wettability for self-cleaning effects. Many of these systems found in biology possess unique surface properties recognised to regulate cell behaviour. Integration of such natural surface properties in biomaterials can bring about novel cell responses in vitro and provide greater insights into the processes occurring at the cell-biomaterial interface. Using natural surfaces as templates for bioinspired design can stimulate progress in the field of regenerative medicine, tissue engineering and biomaterials science. This literature review aims to combine the state-of-the-art knowledge in natural and nature-inspired surfaces, with an emphasis on material properties known to affect cell behaviour.

ASPIRIN MODIFIES RED BLOOD CELL BEHAVIOUR (RBC) IN THE PLATELET-RBC INTERACTION

1987 ◽  
Author(s):  
M T Santos ◽  
J Aznar ◽  
J Valles ◽  
J L Perez-Reguejo
Keyword(s):  
Single Dose ◽  
Blood Cell ◽  
Platelet Activation ◽  
Red Blood Cell ◽  
Normal Subjects ◽  
Antithrombotic Agent ◽  
Cell Behaviour ◽  
Insight Into

RBC stimulate the initial stages of platelet activation by collagen as evaluated by the BASIC wave (Perez-Requejo et al. Thromb Haemostas 54:799 1985). In order to get some insight into the mechanisms of platelet-RBC interactions, a BASIC wave was induced by lug/ml of collagen after mixing "in vitro" platelets and RBC obtained both before and two hours after a single dose of 500 mg of ASA from normal subjects. The TXB2 formed was also evaluated. The results show (Table) that non aspirinized RBC (non-ASA-RBC) increase the BASIC wave intensity of aspirinized platelets (ASA-PRP) by a cyclooxygenase-independent pathway since no increase in TXB2 was observed (Exp 1), while both non-ASA-RBC (Exp 2) and ASA-RBC (Exp 3) activate non-ASA platelets with theparticipation of the cyclooxygenase system, since an increase in TXA2 was found.A comparison of the effect of non-ASA-RBC (Exp 1) and ASA-RBC (Exp 4) on aspirinized platelets shows that ASA modifies the RBC behaviour associated with estimulation of platelets by a cyclooxygenase-independent pathway. This effect of ASA on RBC is nottransient and lasts at least 48 hours after ASA ingestion. In addition, when asmall proportion of nonASA platelets (10%) is mixed with aspirinized platelets(90%) and ASA-RBC - a situation that can be encountered "in vivo" inthe hours following ASA ingestion - the intensity of the BASIC wave is 89% of that obtained when all the platelets are non aspirinized. This RBC effect on the mixtureof ASA and nonASA platelets, may help explain the sometimes contradictory effect of ASA as an antithrombotic agent.

Mechanisms of damage and repair in multiple sclerosis — a review

1995 ◽  
Vol 1 (2) ◽  
pp. 61-72 ◽  
Author(s):  
J Zajicek ◽  
A Compston
Keyword(s):  
Complement Activation ◽  
Cell Injury ◽  
Pathological Features ◽  
Cell Behaviour ◽  
Perivascular Inflammation ◽  
In Vitro Systems ◽  
Injury And Repair ◽  
Necrosis Factor

Pathological features of MS include perivascular inflammation and demyelination with oligodendrocyte loss; in addition, attempts at remyelination are of ten unsuccessful and may culminate in astrocytic scarring. One approach to investigating the biological principles underlying these processes is to use in vitro systems to analyse single-cell behaviour as well as cell-cell interactions. This paper reviews such data concerned with cell injury and repair which illuminate both demyelination and remyelination. In tissue culture oligodendrocytes are susceptible to injury via cell-mediated and humoral mechanisms. Substances including complement and tumour necrosis factor are capable of killing rat oligodendrocytes in vitro; surface complement activation also initiates a number of intracellular processes within oligodendrocytes as well as providing ligands for phagocytic interactions. The reasons for oligodendrocyte complement activation are discussed, but it appears that species differences exist when extrapolating these data to humans. Myelination and remyelination can also be studied both in vitro and in vivo using defined cell populations. Results from these studies may eventually help to explain some pathological features of MS, including astrocytosis and factors governing the limits of remyelination.

scholarly journals Anti-carcinogenic effects of exercise-conditioned human serum: evidence, relevance and opportunities

2021 ◽  
Author(s):  
Richard S. Metcalfe ◽  
Rachael Kemp ◽  
Shane M. Heffernan ◽  
Rachel Churm ◽  
Yung-Chih Chen ◽  
...  
Keyword(s):  
Physical Activity ◽  
Cancer Cell ◽  
Cancer Biology ◽  
Tumour Growth ◽  
Exercise Physiology ◽  
Future Research ◽  
Cell Behaviour ◽  
Rna Molecules

AbstractRegular physical activity reduces the risk of several site-specific cancers in humans and suppresses tumour growth in animal models. The mechanisms through which exercise reduces tumour growth remain incompletely understood, but an intriguing and accumulating body of evidence suggests that the incubation of cancer cells with post-exercise serum can have powerful effects on key hallmarks of cancer cell behaviour in vitro. This suggests that exercise can impact tumour biology through direct changes in circulating proteins, RNA molecules and metabolites. Here, we provide a comprehensive narrative overview of what is known about the effects of exercise-conditioned sera on in vitro cancer cell behaviour. In doing so, we consider the key limitations of the current body of literature, both from the perspective of exercise physiology and cancer biology, and we discuss the potential in vivo physiological relevance of these findings. We propose key opportunities for future research in an area that has the potential to identify key anti-oncogenic protein targets and optimise physical activity recommendations for cancer prevention, treatment and survivorship.

scholarly journals Multivalent ligands control stem cell behaviour in vitro and in vivo

2013 ◽  
Vol 8 (11) ◽  
pp. 831-838 ◽  
Author(s):  
Anthony Conway ◽  
Tandis Vazin ◽  
Dawn P. Spelke ◽  
Nikhil A. Rode ◽  
Kevin E. Healy ◽  
...  
Keyword(s):  
Stem Cell ◽  
Cell Behaviour ◽  
Multivalent Ligands
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