Cell-Molecular Interactions of Nano- and Microparticles in Dental Implantology.

The role of metallic nano- and microparticles in the development of inflammation has not yet been investigated. Soft tissue biopsy specimens of the bone bed taken during surgical revisions, as well as supernatants obtained from the surface of the orthopedic structures and dental implants (control), were examined. Investigations were performed using X-ray microtomography, X-ray fluorescence analysis, and scanning electron microscopy. Histological studies of the bone bed tissues were performed. Nanoscale and microscale metallic particles were identified as participants in the inflammatory process in tissues. Supernatants containing nanoscale particles were obtained from the surfaces of 20 units of new dental implants. Early and late apoptosis and necrosis of immunocompetent cells after co-culture and induction by lipopolysaccharide and human venous blood serum were studied in an experiment with staging on the THP-1 (human monocytic) cell line using visualizing cytometry. As a result, it was found that nano- and microparticles emitted from the surface of the oxide layer of medical devices impregnated soft tissue biopsy specimens. By using different methods to analyze the cell-molecule interactions of nano- and microparticles both from a clinical perspective and an experimental research perspective, the possibility of forming a chronic immunopathological endogenous inflammatory process with an autoimmune component in the tissues was revealed.

Emission and Migration of Nanoscale Particles during Osseointegration and Disintegration of Dental Implants in the Clinic and Experiment and the Influence on Cytokine Production.

The emission of nanoscale particles from the surfaces of dental implants leads to the cumulative effect of particle complexes in the bone bed and surrounding soft tissues. Aspects of particle migration with the possibility of their involvement in the development of pathological processes of systemic nature remain unexplored. The aim of this work was to study protein production during the interaction of immunocompetent cells with nanoscale metal particles obtained from the surfaces of dental implants in the supernatants. The ability to migrate nanoscale metal particles with possible involvement in the formation of pathological structures, in particular in the formation of gallstones, was also investigated. The following methods were used: microbiological studies, X-ray microtomography, X-ray fluorescence analysis, flow cytometry, electron microscopy, dynamic light scattering, and multiplex immunofluorescence analysis. For the first time, titanium nanoparticles in gallstones were identified by X-ray fluorescence analysis and electron microscopy with elemental mapping. The multiplex analysis method revealed that the physiological response of the immune system cells, in particular neutrophils, to nanosized metal particles significantly reduced TNF-a production both through direct interaction and through double lipopolysaccharide-induced signaling. For the first time, a significant decrease in TNF-a production was demonstrated when supernatants containing nanoscale metal particles were co-cultured with proinflammatory peritoneal exudate obtained from the peritoneum of the C57Bl/6J inbred mice line for one day.

Immunopathological Inflammation in the Evolution of Mucositis and Peri-Implantitis.

The purpose of this study was to provide an immuno-mediated substantiation of the etiopathogenesis of mucositis and peri-implantitis based on the results of experimental, laboratory and clinical studies. The biopsy material was studied to identify impregnated nanoscale and microscale particles in the structure of pathological tissues by using X-ray microtomography and X-ray fluorescence analyses. Electron microscopy with energy-dispersive analysis identified the composition of supernatants containing nanoscale metal particles obtained from the surfaces of dental implants. The parameters of the nanoscale particles were determined by dynamic light scattering. Flow cytometry was used to study the effect of nanoscale particles on the ability to induce the activation and apoptosis of immunocompetent cells depending on the particles' concentrations during cultivation with the monocytic cell line THP-1 with the addition of inductors. An analysis of the laboratory results suggested the presence of dose-dependent activation, as well as early and late apoptosis of the immunocompetent cells. Activation and early and late apoptosis of a monocytic cell line when THP-1 was co-cultured with nanoscale metal particles in supernatants were shown for the first time. When human venous blood plasma was added, both activation and early and late apoptosis had a dose-dependent effect and differed from those of the control groups.

Silencing of SARS-CoV-2 with modified siRNA-peptide dendrimer formulation.

BACKGROUND: First vaccines for prevention of Coronavirus disease 2019 (COVID-19) are becoming available but there is a huge and unmet need for specific forms of treatment. In this study we aimed to evaluate the anti-SARS-CoV-2 effect of siRNA both in vitro and in vivo. METHODS: To identify the most effective molecule out of a panel of 15 in silico designed siRNAs, an in vitro screening system based on vectors expressing SARS-CoV-2 genes fused with the firefly luciferase reporter gene and SARS-CoV-2-infected cells was used. The most potent siRNA, siR-7, was modified by Locked nucleic acids (LNAs) to obtain siR-7-EM with increased stability and was formulated with the peptide dendrimer KK-46 for enhancing cellular uptake to allow topical application by inhalation of the final formulation - siR-7-EM/KK-46. Using the Syrian Hamster model for SARS-CoV-2 infection the antiviral capacity of siR-7-EM/KK-46 complex was evaluated. RESULTS: We identified the siRNA, siR-7, targeting SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) as the most efficient siRNA inhibiting viral replication in vitro. Moreover, we showed that LNA-modification and complexation with the designed peptide dendrimer enhanced the antiviral capacity of siR-7 in vitro. We demonstrated significant reduction of virus titer and lung inflammation in animals exposed to inhalation of siR-7-EM/KK-46 in vivo. CONCLUSIONS: Thus, we developed a therapeutic strategy for COVID-19 based on inhalation of a modified siRNA-peptide dendrimer formulation. The developed medication is intended for inhalation treatment of COVID-19 patients.

Mitochondria and Lipid Droplets: Focus on the Molecular Structure of Contact Sites in the Pathogenesis of Metabolic Syndrome.

Metabolic syndrome (MetS) is a complex of serious pathologies with a high prevalence worldwide. Disruption of mitochondrial biogenesis and its interaction with other cell organelles plays an important role in the development of MetS. Studies have revealed the phenotypic and functional heterogeneity of mitochondria that exist within a single cell and can regulate metabolic signaling pathways, influencing the development of metabolic diseases. Excessive intake of fatty acids leads to changes in fatty acid metabolism that affect the biology of important cell organelles - the lipid droplets, whose specific biology is not fully understood. Perhaps targeted molecular genetic stimulation aimed at regulating the contact between mitochondria and lipids can break the vicious cycle of inflammation in MetS and restore normal cell function, reducing the risk of developing concomitant pathologies. The review describes potential (promising) therapeutic molecular targets associated with mitochondria and lipid droplets, focusing on the proteins involved in their contact and emphasizing their role in the pathogenesis of MetS.

MicroRNA Regulation of Bone Marrow Mesenchymal Stem Cells in the Development of Osteoporosis in Obesity.

Obesity and osteoporosis are global health problems characterized by high rates of prevalence and mortality due to complications. As people with visceral obesity age, the adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) increases, and adipocytes become the predominant stromal cells in the bone marrow microenvironment, which hinders the physiological regeneration and mineralization of bone tissue. Primary and secondary osteoporosis remain severe progressive diseases. Both osteoporosis and obesity are associated with microRNAs (miRNAs) that induce adipogenesis and osteoresorption. This review presents analyses of the roles and clinical potential of miRNAs in the epigenetic control of BMSC differentiation and the formation and function of osteoclasts in osteoporosis with and without obesity. Understanding the fine-tuned regulation of the expression of genes critical for the balance of osteogenesis/osteolysis processes may provide hope for the development of effective and safe osteoporosis therapies in the future.

Assessment of dental implant surface stability at the nanoscale level.

OBJECTIVES: To study the oxide layer stability of certified dental implants of system "P", made based on TiO2 alloy with carbon coating. To perform a comparative statistical analysis of the obtained data with the available data for the dental implants of systems "A" and "B". METHODS: X-ray microtomography and X-ray fluorescence analysis were used to study soft tissue biopsy specimens. Supernatants were studied by dynamic light scattering and transmission electron microscopy when simulating free emission of nanoscale metal oxide particles from the surface of dental implants as well as when simulating physical loading. A comparative analysis of three parameters of nanoscale particles was performed by statistical data analysis. The surface of the "P" system dental implant with surface treatment was analyzed by scanning electron microscopy. RESULTS: Both free emission of nanoscale oxide layer particles and yield of nano- and microscale particles during simulation of physical load were confirmed. Statistically significant differences were noted in a comparative analysis of the size and frequency of occurrence of these particles in the supernatants obtained from the surfaces of three dental implant systems. The elemental composition of the particles and the composition and structure of the "P" system dental implants themselves were analyzed. SIGNIFICANCE: The developed method of dynamic light scattering can be used to compare the stability of the oxide layer of standardized medical products manufactured on the basis of the TiO2 alloy.

Analysis of miRNAs Profiles in Serum of Patients With Steatosis and Steatohepatitis.

Non-alcoholic fatty liver disease (NAFLD) is emerging as one of the most common chronic liver diseases worldwide, affecting 25% of the world population. In recent years, there has been increasing evidence for the involvement of microRNAs in the epigenetic regulation of genes taking part in the development of steatosis and steatohepatitis-two main stages of NAFLD pathogenesis. In the present study, miRNA profiles were studied in groups of patients with steatosis and steatohepatitis to compare the characteristics of RNA-dependent epigenetic regulation of the stages of NAFLD development. According to the results of miRNA screening, 23 miRNAs were differentially expressed serum in a group of patients with steatohepatitis and 2 in a group of patients with steatosis. MiR-195-5p and miR-16-5p are common differentially expressed miRNAs for both steatosis and steatohepatitis. We analyzed the obtained results: the search for target genes for the differentially expressed miRNAs in our study and the subsequent gene set enrichment analysis performed on KEGG and REACTOME databases revealed which metabolic pathways undergo changes in RNA-dependent epigenetic regulation in steatosis and steatohepatitis. New findings within the framework of this study are the dysregulation of neurohumoral pathways in the pathogenesis of NAFLD as an object of changes in RNA-dependent epigenetic regulation. The miRNAs differentially expressed in our study were found to target 7% of genes in the classic pathogenesis of NAFLD in the group of patients with steatosis and 50% in the group of patients with steatohepatitis. The effects of these microRNAs on genes for the pathogenesis of NAFLD were analyzed in detail. MiR-374a-5p, miR-1-3p and miR-23a-3p do not target genes directly involved in the pathogenesis of NAFLD. The differentially expressed miRNAs found in this study target genes largely responsible for mitochondrial function. The role of miR-423-5p, miR-143-5p and miR-200c-3 in regulating apoptotic processes in the liver and hepatocarcinogenesis is of interest for future experimental studies. These miR-374a, miR-143, miR-1, miR-23a, and miR-423 have potential for steatohepatitis diagnosis and are poorly studied in the context of NAFLD. Thus, this work opens up prospects for further studies of microRNAs as diagnostic and therapeutic biomarkers for NAFLD.

Conserved pan-cancer microenvironment subtypes predict response to immunotherapy.

The clinical use of molecular targeted therapy is rapidly evolving but has primarily focused on genomic alterations. Transcriptomic analysis offers an opportunity to dissect the complexity of tumors, including the tumor microenvironment (TME), a crucial mediator of cancer progression and therapeutic outcome. TME classification by transcriptomic analysis of >10,000 cancer patients identifies four distinct TME subtypes conserved across 20 different cancers. The TME subtypes correlate with patient response to immunotherapy in multiple cancers, with patients possessing immune-favorable TME subtypes benefiting the most from immunotherapy. Thus, the TME subtypes act as a generalized immunotherapy biomarker across many cancer types due to the inclusion of malignant and microenvironment components. A visual tool integrating transcriptomic and genomic data provides a global tumor portrait, describing the tumor framework, mutational load, immune composition, anti-tumor immunity, and immunosuppressive escape mechanisms. Integrative analyses plus visualization may aid in biomarker discovery and the personalization of therapeutic regimens.

Amorphous-Crystalline Calcium Phosphate Coating Promotes In Vitro Growth of Tumor-Derived Jurkat T Cells Activated by Anti-CD2/CD3/CD28 Antibodies.

A modern trend in traumatology, orthopedics, and implantology is the development of materials and coatings with an amorphous-crystalline structure that exhibits excellent biocopatibility. The structure and physico-chemical and biological properties of calcium phosphate (CaP) coatings deposited on Ti plates using the micro-arc oxidation (MAO) method under different voltages (200, 250, and 300 V) were studied. Amorphous, nanocrystalline, and microcrystalline statesof CaHPO4 and ß-Ca2P2O7 were observed in the coatings using TEM and XRD. The increase in MAO voltage resulted in augmentation of the surface roughness Ra from 2.5 to 6.5 µm, mass from 10 to 25 mg, thickness from 50 to 105 µm, and Ca/P ratio from 0.3 to 0.6. The electrical potential (EP) of the CaP coatings changed from -456 to -535 mV, while the zeta potential (ZP) decreased from -53 to -40 mV following an increase in the values of the MAO voltage. Numerous correlations of physical and chemical indices of CaP coatings were estimated. A decrease in the ZP magnitudes of CaP coatings deposited at 200-250 V was strongly associated with elevated hTERT expression in tumor-derived Jurkat T cells preliminarily activated with anti-CD2/CD3/CD28 antibodies and then contacted in vitro with CaP-coated samples for 14 days. In turn, in vitro survival of CD4+ subsets was enhanced, with proinflammatory cytokine secretion of activated Jurkat T cells. Thus, the applied MAO voltage allowed the regulation of the physicochemical properties of amorphous-crystalline CaP-coatings on Ti substrates to a certain extent. This method may be used as a technological mechanism to trigger the behavior of cells through contact with micro-arc CaP coatings. The possible role of negative ZP and Ca2+ as effectors of the biological effects of amorphous-crystalline CaP coatings is discussed. Micro-arc CaP coatings should be carefully tested to determine their suitability for use in patients with chronic lymphoid malignancies.

[IGG4-related diseases in endocrinology].

Immunoglobulin-G4-related disease (IgG4-RD) is a chronic immunomediated pathology of different organs of local or systemic nature, which has been established as a separate clinical entity in the early 2000s and is characterized by storiform fibroid inflammation of the affected tissues, their increase, and elevated serum immunoglobulin-G4 (IgG4) levels. The most common manifestations of the disease are major salivary and lacrimal gland enlargement, lymphadenopathy and type 1 autoimmune pancreatitis (AIP1), however, other organs may be also involved (the thyroid, eyes, meninges, heart, lungs, kidneys, aorta, upper airways, mesentery, etc.). The effectiveness of treatment of IgG4-RD, as well as other pathological conditions, is also determined by the timely diagnosis. However, the latter is complicated due to the variety of clinical manifestations and rather variable diagnostic criteria. It is necessary to constantly update the evidence-based knowledge and diagnostic algorithms within this pathology in order to overcome the difficulties, and involve immunologists, endocrinologists, pathologists and specialists in other spheres. This review provides information about the etiology, pathogenesis, and current methods of diagnosis and treatment of IgG4-related diseases, as well as examples of some manifestations of IgG4-RD that an endocrinologist may face in practice.

Indirect broadband optical monitoring with multiple witness substrates.

We present an indirect broadband optical monitoring approach based on using several witness substrates that are brought to a measurement position in a special sequence. Different witness substrates are used to monitor not groups of successive design layers but specially chosen design layers. An attractive feature of the presented monitoring approach is the ability to reliably control thin dielectric and metal layers. Considered examples demonstrate a good accuracy of the proposed approach.

TREC and KREC Levels as a Predictors of Lymphocyte Subpopulations Measured by Flow Cytometry.

Primary immunodeficiency diseases (PID) is a heterogeneous group of disorders caused by genetic defects of the immune system, which manifests clinically as recurrent infections, autoimmune diseases, or malignancies. Early detection of other PID remains a challenge, particularly in older children due to milder and less specific symptoms, a low level of clinician PID awareness and poor provision of hospital laboratories with appropriate devices. T-cell recombination excision circles (TREC) and kappa-deleting element recombination circle (KREC) in a dried blood spot and in peripheral blood using real-time polymerase chain reaction (PCR) are used as a tool for severe combined immune deficiency but not in PID. They represent an attractive and cheap target for a more extensive use in clinical practice. This study aimed to assess TREC/KREC correspondence with lymphocyte subpopulations, measured by flow cytometry and evaluate correlations between TREC/KREC, lymphocyte subpopulations and immunoglobulins. We carried out analysis of data from children assessed by clinical immunologists at Speransky Children's Hospital, Moscow, Russia with suspected immunodeficiencies between May 2013 and August 2016. Peripheral blood samples were sent for TREC/KREC, flow cytometry (CD3, CD4, CD8, and CD19), IgA, IgM, and IgG analysis. A total of 839 samples were analyzed for using TREC assay and flow cytometry and 931 KREC/flow cytometry. TREC demonstrated an AUC of 0.73 (95% CI 0.70-0.76) for CD3, 0.74 (95% CI 0.71-0.77) for CD4 and 0.67 (95% CI 0.63-0.70) for CD8, respectively, while KREC demonstrated an AUC of 0.72 (95% CI 0.69-0.76) for CD19. Moderate correlation was found between the levels of TREC and CD4 (r = 0.55, p < 0.01) and KREC with CD19 (r = 0.56, p < 0.01). In this study, promising prediction models were tested. We found that TREC and KREC are able to moderately detect abnormal levels of individual lymphocyte subpopulations. Future research should assess associations between TREC/KREC and other lymphocyte subpopulations and approach TREC/KREC use in PID diagnosis.

CD Antigens: Review of Data Obtained by April' 98.

CD nomenclature may be considered as chronologically set up list of elucidated molecules with each molecule number characterized by the time when it was discovered and thus by the advances in immunology. The Nomenclature Committee of World Health Organization (WHO) and International Union of Immunological Societies (IUIS) have a specialized classification department - Subcommittee on CD Nomenclature. Registration and indexing of the particular CD number to the selected clusters is carried out at International Workshops on Human Differentiation Antigens. The last 6th International Workshop was held in 1996, Kobe, Japan. In the present review we force to briefly characterize all already elucidated CD molecules that is given in a form of multicomponent table. The table partly created by us was based on the data of the last International Workshop and literature data covering the 1997-1998 period. As a commentary to the CD nomenclature table we shall try to describe structure and functions of the main families and domains, to which the majority of known CD molecules may be attributed.

Adhesion of Fibroblasts to Immobilized alpha(2)-Macroglobulin.

This study examines effects of alpha(2)-macroglobulin (alpha(2)M) on adhesion of fibroblasts. Native alpha(2)M and transformed form of alpha(2)M, alpha(2)M-plasmin, were bound to plastic. Adhesion of mouse L929 and human embryo M-19 fibroblasts to immobilized alpha(2)M was estimated under various conditions by counting adherent cells using videomicroscopy and computer-assisted image analysis. alpha(2)M-plasmin, bound to plastic, induced adhesion and spreading of mouse L929 and human M-19 fibroblasts. Neither native alpha(2)M nor plasmin alone did not induce fibroblast adhesion. The adhesion to alpha(2)M-plasmin was undetectable at 4 degrees C, as well as when sodium azide was added or divalent ions were removed. These findings provide novel information on alpha(2)M functions. On the basis of these observations we hypothesized that alpha(2)M, immobilized in the extracellular matrix, can participate in the regulation of microenvironment effects on the cells, and, in particular, influence on fibroblast adhesion.

Method to evaluate the proliferation of activated lymphocytes in a three-dimensional collagen matrix.

It is well known that the enhancement of the cell-matrix interactions represents one of the early steps in the process of lymphocyte activation. However, the information regarding the role of these interactions in the late stages of lymphocyte activation (in particular, the proliferation) is still controversial. This is basically due to the absence of adequate experimental models. In the present work we carried out a step-by-step modification of a well-studied model of mitogen-stimulated lymphocyte activation, adjusting it to the conditions of a three-dimensional collagen matrix (3D-CM). All the changes added to the standard procedure in the process of this modification were rigorously controlled using various experimental models. The final version of the method includes the following steps: (i) 24-h lymphocyte (lymphocyte fraction from mouse spleen) preincubation with mitogens (Con A or LPS) with a subsequent cell wash (parameters being controlled: irreversible lymphocyte activation, independence of the proliferation from cell-cell interactions); (ii) transfer of the activated lymphocytes to (3)H-thymidine containing 3D-CM and incubation for 48 h (controlled parameters: distribution of the radioactive label within the 3D-CM and its biological accessibility to lymphocytes); (iii) degradation of the 3D-CM with bacterial collagenase and cell transfer onto glass fiber filters (controlled parameters: cell viability after cultivation in the 3D-CM and treatment with the collagenase). With this method we found that the proliferation of the Con A- and LPS-stimulated lymphocytes in 3D-CM was dramatically inhibited (by 66.5 +/- 14.9% and by 88.1 +/- 10.2%, respectively). The discovered inhibition of the lymphocyte proliferation was not a consequence of either the ineffectiveness of the mitogens, the disruption of the cell-cell interactions, an insufficient inclusion of the radioactive label into cells, or of a decreased cell viability.

Binding of alpha2-macroglobulin to collagen type I: modification of collagen matrix by alpha2-macroglobulin induces the enhancement of macrophage migration.

Alpha2-macroglobulin (a2M) secreted by tissue macrophages and fibroblasts functions in the environment of extracellular matrix macromolecules. We supposed that it may interact with these molecules and change the properties of extracellular matrix. Modified variant of ELISA was used to prove the direct binding of human a2M to collagen. Native and transformed by plasmin a2M, as well as plasmin, used as the control, were labeled by biotin. It has been found that the transformed, but not the native a2M form binds to type I collagen molecules: K(d)=(1.168 +/- 1.14) x 10(-11) M. The data obtained give a strong evidence of high power of the interaction between a2M and type I collagen: practically no reverse dissociation may be seen for such a binding. The modification of three-dimensional collagen matrix by binding to the transformed a2M resulted in the enhancement of migration of macrophages, carrying the receptors for a2M, but not splenocytes that lack for such receptors. Our results allow to suggest that a2M may be one of the components of extracellular matrix, and may change the properties of microenvironment for immunocompetent cells during the processes of inflammation, reparation and tumor invasion.

Alpha2-Macroglobulin Modulates Interactions between Lymphocytes and Fibroblasts.

The aim of the present study was to evaluate the influence of apha2-macroglobulin (alpha(2)M) on lymphocyte adhesion to fibroblasts. Peripheral blood lymphocytes from healthy donors and two fibroblast lines (human diploid embryo fibroblasts M-19 and mouse transformed fibroblasts L929) were used in the experiments. alpha(2)M treatment of fibroblast monolayer appeared to result in the enhancement of lymphocyte adhesion to fibroblasts. The number of attached lymphocytes was increased by 2-2.5 times. It should be noted that the effect of alpha(2)M didn't depend on the conformational molecule changes, since either native or methylamine or plasmin transformed alpha(2)M approximately at the same fashion increased the lymphocyte adhesion to both allogeneic and xenogeneic fibroblasts. B lymphocytes were predominant cells that were attached to fibroblast monolayer without alpha(2)M treatment. However the percentage of adherent T lymphocytes was increased substantially after the fibroblast monolayer treatment by alpha(2)M. Subpopulation analysis has shown that fibroblast pretreatment by alpha(2)M didn't result in a selective adhesion of CD4(+) or CD8(+) T lymphocytes, but increased the adhesiveness for both T lymphocyte subpopulations. The data obtained demonstrate that besides its participation in the processes of fibroblast adhesion alpha(2)M is capable to modify the contact interaction of these cells with lymphocytes that may have an influence on the functional consequences of this process.

Low-Molecular Collagen Peptides Have Different Effects on Peritoneal Macrophages and Neutrophils.

Two types of phagocytes - neutrophils and macrophages, are very important participants in inflammation. However, the roles played by these cells in the regulation of an inflammation are radically different. Neutrophils initiate and ensure the alteration phase. Macrophages, to the contrary, regulate the transition of an inflammation from alternative processes to reparative. During the early stages of an inflammation, under the effect of proteases and free radicals, destruction of collagen proteins occurs and a large number of low-molecular peptides are formed, the concentration of which changes as the inflammatory reaction develops. The object of this work was to study the effect of the total fraction of low-molecular type I collagen peptides on the key functions of neutrophils and macrophages. Under the action of the wide range of concentrations of the collagen peptides (1-1000 &mgr;g/ml), activation of the neutrophil migration into the three-dimensional collagen matrix, amplification of PMA-induced production of free radicals and reduction of apoptosis of those cells were observed. The action of collagen peptides on the functions of macrophages had the opposite effect, i.e. they caused inhibition of the macrophage migration and reduction of PMA-induced production of free radicals. Furthermore, at a concentration of 100 &mgr;g/ml the collagen peptides reliably reduced the apoptosis of macrophages. Thus, collagen peptides are potent regulators of an inflammation, promoting the successive development of its phases through regulation of the functional state of phagocytes.

Low Molecular Weight Collagen Peptides Affect Migration, Proliferation and Apoptosis of Mouse Spleen Lymphocytes.

As a consequence of inflammatory tissue degradation collagen proteolysis products may be accumulated in the altered tissue. In this connection, we elaborated a hydrolysis scheme to obtain low molecular weight collagen peptides analogous to those produced in vtiro. To elucidate a possible role of collagen peptides during inflammation their action on lymphocyte migration, proliferation and apoptosis was studied at a wide range of concentrations 1-1000 &mgr;g/ml. The observed effects of peptides were different in three concentration ranges - low (1-50 &mgr;g/ml), middle (50-250 &mgr;g/ml) and high (250-1000 &mgr;g/ml). At high concentrations collagen peptides inhibited lymphocyte migration into 3D collagen matrix, and proliferation, including both spontaneous and stimulated. The middle peptide range induced lymphocyte apoptosis and modulated proliferation. Similar to middle ones, low concentration of collagen peptides modulated lymphocyte proliferation and their effect was the most pronounced. The three concentration ranges may presumably fit different stages of inflammation, since collagen degradation is associated with intensity of tissue alteration. Hence, collagen peptides may control lymphocyte functioning at different inflammation stages. Being naturally produced due to inflammatory tissue degradation, collagen peptides may be considered as complex inflammatory regulator like other traditionally discussed mediators (cytokines, chemokines, lipid mediators, etc.).