Platelets – an important element of the immune system

2013 ◽  
Vol 16 (2) ◽  
pp. 407-413 ◽  
Author(s):  
A. Trzeciak-Ryczek ◽  
B. Tokarz-Deptuła ◽  
W. Deptuła

Abstract Platelets are anucleate cells derived from the megakaryocyte series, and have long been considered only as cells responsible for coagulation and the fibrinolysis process. However, recently more data shows that they are also effector cells in the inflammatory response and important elements of the immunological response. Platelets store and release many biologically active substances, including growth factors, cytokines and chemokines (tab. 1), which actively affect i.a. elements of the immune system, and thus become regulators of immunity and mediators of inflammatory response. Their impact on the immune system cells is also associated with the induction of leucocytes and progenitor cells to the site of pathogen permeation or vascular injury inflow, as well as endothelial cells. Interacting with neutrophils, monocytes and lymphocytes, they not only activate them, but also form platelet-leukocyte aggregates that immobilise pathogens and prevent their spreading. Furthermore, platelets are capable of absorbing pathogens, affecting anti-infection immunity of the system. It is also assumed that the presence of receptors on their surface, such as Toll-like receptors (TLRs), affects their initiation and activity of the immunological response.

2021 ◽  
pp. 55-58
Author(s):  
V. V. Bondarenko

In recent years, the possibilities of a dermatologist in the treatment of patients with chronic dermatoses have significantly expanded due to the emergence of new highly effective methods, such as autologous blood plasma enriched with platelet-rich-growth factors (platelet-rich-plasma, PRP). The positive results of using this technology due to its constituent growth factors, cytokines and other biologically active substances, which have a pronounced normalizing effect on the processes of tissue repair and regeneration, expands the possibilities of its use in such skin diseases as erosive and ulcerative lichen planus, scleroatrophic lichen, acne and post-acne. The aim of this review was to analyze the literature on the mechanisms of PRP action in patients with dermatological diseases.


Author(s):  
I.V. Tsiganenko ◽  
L.K. Ovcharenko

The work considers the causes of the coronary X syndrome development in women by assessing the experimental group and the control group with typical angina pectoris with angiographically altered vessels. Each group included 30 patients. When studingy medical records of the patients in the study group, we found out that in the reproductive period all of them had hyperestrogenemia, confirmed by the laboratory data, with the corresponding consequences in the form of various gynecological diseases, while the patients of the control group had unburdened gynaecological history. In terms of the lipid spectrum, the results turned out to be opposite. In the experimental group, the rates were within the normal range, and the control level of LDL-C significantly exceeded the required values. Despite the fact that estrogens increase the concentration of high density lipoprotein (HDL) in the blood and lower the content of low density lipoprotein (LDL) that are atherogenic, their surplus has a less negative effect than their lack, as the risk of developing atherosclerosis increases with decreasing concentration, and with an increase there is a risk of developing endothelial dysfunction, which provokes the development of coronary syndrome X. These date confirm the development of endothelial dysfunction in the patients of the experimental group with hyperestrogenemia in the history resulted from the impairment of the process of proliferation of endothelial cells with subsequent imbalance of secretion of biologically active substances. Among them, there is nitric oxide, which causes the relaxation of smooth myocytes, thus resulting in vasodilatation, and endothelins, providing the opposite, vasodilating effect. Prostacyclines and thrombomodulins secreted by the vascular endothelium in physiological conditions, counteract platelet aggregation. In the case of damage to the vascular wall, the production of prostacyclin and thrombomodulin is suppressed, but the release of thromboplastin, platelet activation factor and von Willerband factor activates that promote platelet aggregation and blood clotting. Under the participation of other physiologically active substances, selectins, endothelial cells promote adhesion to their surface and further penetration into the site of inflammation of neutrophils, blood acidophils. Selectin is accumulated in the cytoplasm of the endothelial cells in the form of specific electron-cellular inclusions, the so-called bodies of Weibel-Palade. Normally, vascular endothelium is impervious to blood components. However, being affected by a number of factors, and in particular histamine, endothelial cells lose contact with each other and decrease in number. This leads to the release of water and plasma proteins into the intercellular medium causing oedema. Due to the ability of the inner layer of vessels to produce a large number of biologically active substances, such changes can hardly be corrected by therapy.


2014 ◽  
Vol 2014 ◽  
pp. 1-15 ◽  
Author(s):  
Laurissa Ouaguia ◽  
Dhafer Mrizak ◽  
Sarah Renaud ◽  
Olivier Moralès ◽  
Nadira Delhem

Virus infections are involved in chronic inflammation and, in some cases, cancer development. Although a viral infection activates the immune system’s response that eradicates the pathogen mainly through inflammatory mechanisms, it is now recognized that this inflammatory condition is also favorable to the development of tumors. Indeed, it is well described that viruses, such as hepatitis C virus (HCV), Epstein Barr virus (EBV), human papillomavirus (HPV) or human T-cell lymphotropic virus type-1 (HTLV-1), are important risk factors for tumor malignancies. The inflammatory response is a fundamental immune mechanism which involves several molecular and cellular components consisting of cytokines and chemokines that are released by various proinflammatory cells. In parallel to this process, some endogenous recruited components release anti-inflammatory mediators to restore homeostasis. The development of tools and strategies using viruses to hijack the immune response is mostly linked to the presence of regulatory T-cells (Treg) that can inhibit inflammation and antiviral responses of other effector cells. In this review, we will focus on current understanding of the role of natural and induced Treg in the control and the resolution of inflammatory response in HCV-, HTLV-1-, and EBV-associated cancers.


2017 ◽  
Vol 86 (2) ◽  
pp. 173
Author(s):  
Teresa Matthews-Brzozowska ◽  
Aleksandra Krzyżanowska ◽  
Maciej Lichaj

Aging is a natural, unavoidable physiological process of every human being. Aesthetic medicine, a rapidly growing on field of medicine, slows down this process. Autonomic mezotherapy is a specific type of needle mezotherapy using autologous platelets suspended in a small amount of plasma. Possibilities of use of blood preparations were discussed using 9 items of national literature and 5 foreign reports. The role of the plaques is not only a hemostatic function but also a function of cellular repair by the content of biologically active substances. The biostimulating effect consists in the activation of different cell types by growth factors. The technological change of the gel formulation creates new possibilities for the extension of aesthetic medicine.


2005 ◽  
Vol 72 (S1) ◽  
pp. 66-72 ◽  
Author(s):  
Antonella Baldi ◽  
Politis Ioannis ◽  
Pecorini Chiara ◽  
Fusi Eleonora ◽  
Chronopoulou Roubini ◽  
...  

The protein fraction of milk contains several components with physiological significance for the development of the newborn. Among them, immunomodulatory peptides and lactoferrin exemplify the complexity of biologically active substances of milk. Immunomodulatory peptides have latent activity within the native protein and are generated after proteolysis during gastrointestinal transit. Once they are generated, they modulate mucosal immunity, possibly by guiding the local immune system until it develops its full functionality. Lactoferrin is another milk bioactive compound with nutritional and health promoting properties; it modulates the microbial intestinal environment, displays anti-microbial activity against various pathogens and stimulates the establishment of beneficial microflora. The following overview focuses on the importance of immunomodulatory peptides and lactoferrin for the maturation of intestine and immune system that are functionally immature in the newborn.


2013 ◽  
Vol 4 (1) ◽  
pp. 122-127 ◽  
Author(s):  
Anatoliy Vasilyevich Babichev

Formation and excretion of thrombogenous and athrombogenous factors by endothelial cells is a constant physiological process taking place in all vessels. Endothelium is a huge endocrine gland which generates a wide spectrum of biologically active substances. Biologically active substances of endothelium are involved in many hemostasis mechanisms and regulation of local blood flow. BAS composition is determined by status of endothelial cells. In physiological state BAS of endothelium provide adequate local blood flow by synthesizing powerful anticoagulants, vasodilators and other biologically active substances. Activity of endothelium in physiological conditions provides trophism of tissues and fulfils protective function. Disturbance of any function or structure of endothelium significantly changes the spectrum of biologically active substances. Endothelium starts to secrete aggregants, coagulants, vasoconstrictors and other factors many of which contribute to generalization of the pathological process.


2021 ◽  
Vol 12 ◽  
Author(s):  
Beata Tokarz-Deptuła ◽  
Joanna Palma ◽  
Łukasz Baraniecki ◽  
Michał Stosik ◽  
Roman Kołacz ◽  
...  

The article presents the function of platelets in inflammation as well as in bacterial and viral infections, which are the result of their reaction with the endovascular environment, including cells of damaged vascular endothelium and cells of the immune system. This role of platelets is conditioned by biologically active substances present in their granules and in their specific structures – EV (extracellular vesicles).


2021 ◽  
Vol 10 (1) ◽  
pp. 83-90
Author(s):  
A. Y. Vaza ◽  
A. M. Fain ◽  
N. V. Borovkova ◽  
I. E. Galankina ◽  
M. S. Makarov ◽  
...  

BACKGROUND Fractures of the proximal humerus are more common in older adults. Two options for surgical treatment of the same fractures are routinely performed — primary arthroplasty and osteosynthesis with metal fixators. Both methods are most effective in elderly patients for augmentation of the proximal humerus. For this purpose, methyl methacrylate cement or bone allo-/autografts are used. However, the incidence of unsatisfactory functional results after surgery remains high.AIM OF STUDY To develop allogeneic graft to strengthen the proximal humerus in the osteosynthesis of a comminuted fracture with a lack of bone tissue which has osteoconductive properties and capable of being a carrier of biologically active substances.MATERIAl AND METHODS The head, neck and portion of diaphysis of a fibula of a cadaver were used for a graft. The graft 6–8 cm long was formed and saturated with a collagen solution. Ten patients with 4-fragment fractures of the proximal humerus underwent surgery. X-rays and computed tomography of the operated joint were performed the day after surgery, and then, 6 weeks, 6 months, and one year after the surgery. The follow-up period ranged from 6 to 18 months.RESUlTS When evaluating osteoconductive effect in cell culture during saturation with collagen, the content cells on the surface of bone was 5–8 thousand/cm2 and 16–18 thousand/cm2 on the sample, saturated with plasma and growth factors. The studied bone grafts were biocompatible and non-toxic for fibroblast culture. On the surface of the bone graft without collagen adhesion of minimum number of cells occurred. After saturation of the graft with collagen, the adhesive activity of cells on the bone matrix increased, which indicated the presence of an osteoconductive effect. The addition of plasma saturated with growth factors promoted an increase in the number of adhered cells; therefore, the graft can be used as a carrier of biologically active substances. Postoperative X-ray didn’t reveal secondary varus displacement of the head in any patient (except for ununiformed fracture case).CONClUSION The developed graft is non-toxic, does not possess immunogenicity, has more pronounced osteoconductive properties in comparison with native bone allografts, which contributes to its colonization with cells. The use of such a graft in clinical practice makes it possible to achieve healing of the fracture and prevent secondary displacement of fragments. 


2021 ◽  
Vol 11 (4) ◽  
pp. 245-254
Author(s):  
E. A. Praskurnichiy ◽  
S. A. Gracheva ◽  
N. V. Kugan ◽  
O. M. Maslennikova

The review examines the key aspects of the pathogenesis of alopecia in endocrine system pathology. The role of hormones, growth factors, cytokines and other biologically active substances has been demonstrated. Alopecia is a frequent symptom that can be the result of not only gerontological, but also endocrinological problems. Therefore, time-consuming differential diagnosis is often necessary. Diagnosis is more effective if a team of specialists is involved: endocrinologist, gynecologist, andrologist, dermatologist / trichologist, and others.


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