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1.
Folia Neuropathol ; 53(2): 128-38, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26216115

RESUMO

Oral tolerance is the natural occurring phenomenon of a decreased immune response to previously fed antigens, which prevents induction of a response to dietary antigens. One of the mechanisms is deletion of T lymphocytes reactive to the fed antigen. Knowing that phenomenon, it seems appropriate to engage this mechanism for treatment of autoimmune diseases. Multiple sclerosis (MS) is an autoimmunological disease which causes neurological impairment in humans. Autoreactive T lymphocytes migrate through the open blood-brain barrier into the central nervous system (CNS), where they recognize myelin antigens as foreign, and induce an inflammatory response against the myelin sheath, which causes demyelination and even axonal loss. Experimental allergic encephalomyelitis (EAE), an animal model of MS, resembles the autoimmunological aspect of the disease. We used a broad spectrum of myelin antigens to induce EAE, and also to induce oral tolerance by giving myelin epitopes intragastrically to rats. The aim of our study was to evaluate whether pig spinal cord hydrolysate given intragastrically is able to evoke oral tolerance in rats with an animal model of MS - EAE. In our experiments we fed female Lewis rats with pig spinal cord hydrolysate at doses of 5, 20 and 100 mg per kg of body weight. We observed diminished clinical symptoms of ongoing EAE in rats fed with all doses of pig spinal cord hydrolysate. In the histopathological study, intensity of the inflammatory process in spinal cord was similar in rats not fed with EAE and in rats fed with lower doses of pig spinal cord hydrolysate. In animals fed with the highest dose of pig spinal cord hydrolysate, intensification of the inflammatory response was observed. These results were confirmed by morphometric evaluations. We found that feeding animals with preparations containing myelin antigens can reduce EAE symptoms, which may indicate oral tolerance induction, but the obtained results also underline the importance of dose of the orally given antigens, because of the possibility of enhancement of the inflammatory process in the CNS.


Assuntos
Encefalomielite Autoimune Experimental/patologia , Tolerância Imunológica/imunologia , Proteínas da Mielina/imunologia , Administração Oral , Animais , Encefalomielite Autoimune Experimental/imunologia , Feminino , Cobaias , Hidrólise , Proteínas da Mielina/farmacologia , Ratos , Ratos Endogâmicos Lew , Suínos
2.
PLoS One ; 9(6): e98073, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24915193

RESUMO

The primary function of hair and fur covering mammalian skin is to provide mechanical and thermal protection for the body. The proteins that constitute hair are extremely resistant to degradation by environmental factors. However, even durable materials can be slowly broken down by mechanical stresses, biodegradation mediated by endogenous enzymes in the skin or host microbes. We hypothesised that the biodegradation products of hair may possess bioprotective properties, which supplement their physical protective properties. Although evolutionary processes have led to a reduction in the amount of hair on the human body, it is possible that the bioprotective properties of hair biodegradation products have persisted. The human skin is exposed to various environmental carcinogenic factors. Therefore, we hypothesised that the potential bioprotective mechanisms of hair degradation products affect melanoma growth. We used pepsin to partially digest hair enzymatically, and this process produced a water-soluble lysate containing a mixture of peptides, including fragments of keratin and keratin-associated proteins. We found out that the mixtures of soluble peptides obtained from human hair inhibited the proliferation of human melanoma cells in vitro. Moreover, the hair-derived peptide mixtures also inhibited the proliferation of B lymphoma cells and urinary bladder cancer cells. Normal human cells varied in their susceptibility to the effects of the lysate; the hair-derived peptide mixtures modulated the proliferation of normal human fibroblasts but did not inhibit the proliferation of human mesenchymal cells derived from umbilical cord stromal cells. These results suggest that hair-derived peptides may represent a new class of anti-proliferative factors derived from basically structural proteins. Identification of active regulatory compounds and recognition of the mechanism of their action might pave the way to elaboration of new anticancer drugs.


Assuntos
Antineoplásicos/farmacologia , Queratinas Específicas do Cabelo/química , Fragmentos de Peptídeos/farmacologia , Hidrolisados de Proteína/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos
3.
Tissue Eng Part C Methods ; 15(3): 365-72, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19719393

RESUMO

Stem cell-based regenerative neurology is an emerging concept for treatment of diseases of central nervous system. Among variety of proposed procedures, one of the most promising is refilling of cystic cavities of injured brain parenchyma with artificial neural tissue. Recent studies revealed that after allogenic transplantation in rodents these tissue-engineered entities were shown efficient in repair of hypoxic/ischemic brain injury. Human umbilical cord blood (HUCB) was recognized to be an efficient and noncontroversial source of neural stem cells (NSC). The main purpose of this study was to generate HUCB-derived neural artificial tissue and investigate their functional properties. Neural organoids formed on human-originated biodegradable scaffolds within 3 weeks and resembled niche structure where immature stem cells (Oct4+ and Sox2+) and proliferating neuroblasts (Nestin+, GFAP+, and Ki67+) were present. Such aggregates were placed on multi-electrode chips and differentiated toward mature neurons (TUJ1+ and MAP2+). These three-dimensional aggregates in contrast to two-dimensional cultures formed functional circuits and generated spontaneous field/action potentials. Our results indicate that three-dimensional environment facilitates maturation of HUCB-derived NSC what should be considered regarding regenerative medicine application.


Assuntos
Sangue Fetal/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Tecido Nervoso/citologia , Tecido Nervoso/crescimento & desenvolvimento , Neurônios/citologia , Neurônios/fisiologia , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Humanos , Técnicas de Cultura de Órgãos/métodos , Engenharia Tecidual/métodos
4.
Acta Neurobiol Exp (Wars) ; 69(1): 73-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19325643

RESUMO

The aim of this study was to use the hydrolysate of pig spinal cord proteins to induce oral tolerance in the animal model of sclerosis multiplex - experimental allergic encephalomyelitis. The female Lewis rats were fed with hydrolysate of pig spinal cord proteins in two doses for one week before immunization, which was induced by injection of guinea pig spinal cord homogenate. At the peak of clinical symptoms (the 13th day post immunization) the rats were sacrificed and the spleen removed. Splenocytes were suspended in a culture medium and placed in microculture plates. The cells were stimulated with homogenate. The cells were cultured for seven days. Proliferation of splenocytes was estimated by means of methyl-3H thymidine incorporation. In supernatants of cultures of splenocytes the level of cytokines INF-gamma, IL-10, IL-4, and TGF-gamma was measured. It was demonstrated that homogenate-induced splenocytes of hydrolysate-fed rats gave rise to low proliferation as compared to the controls used. The IFN-gamma was inhibited in hydrolysate-fed animals. The hydrolysate of pig spinal cord proteins has a modulatory effect on the immune reaction, particularly on the orally-induced antigen-specific modulation of autoimmune response.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Interferon gama/metabolismo , Interleucina-10/metabolismo , Hidrolisados de Proteína/imunologia , Medula Espinal/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/etiologia , Encefalomielite Autoimune Experimental/prevenção & controle , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Cobaias , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Hidrolisados de Proteína/farmacologia , Ratos , Ratos Endogâmicos Lew , Índice de Gravidade de Doença , Medula Espinal/citologia , Baço/citologia , Fatores de Tempo
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