RESUMO
OBJECTIVE: As mesenchymal stromal cells (MSCs) have been proposed as a tool for management or prevention of graft-vs-host disease, we investigated their immunoregulatory properties, their expression of adhesion molecules and galectin-1, and the impact of environment context on these functions. MATERIALS AND METHODS: The effects of MSCs on T-cell proliferation were analyzed using carboxyfluorescein diacetate N-succinimidyl ester labeling. We evaluated the expression of adhesion molecules and galectin-1 by MSCs and the impact of an inflammatory or infectious environment on these expressions. Using neutralizing antibodies against adhesion molecules and a galectin-1 inhibitor, we assessed the role of these molecules in MSC functions. RESULTS: MSCs inhibition of T-cell proliferation depended on MSC concentrations, cell contact, and culture environment. Expression of adhesion molecules and secretion of galectin-1 by MSCs are tightly regulated. Coculture with activated T cells upregulated expression of CD54 (intercellular adhesion molecule 1) and CD58 (lymphocyte function-associated antigen 3) and secretion of galectin-1 by MSCs. Interestingly, in an inflammatory or infectious environment, expression of adhesion molecules and galectin-1 by MSCs was differentially modulated. Furthermore, blocking galectin-1 activity prevented the suppressive potential of MSCs. Neutralization of adhesion molecule activity had no effect on MSC inhibition. CONCLUSION: Galectin-1 plays an important role in MSC immunoregulatory functions, which are depending on cell environment. The present study provides new insights concerning MSC physiology and will increase the safety and efficiency of MSCs in clinical settings.
Assuntos
Antígenos CD58/genética , Galectina 1/genética , Molécula 1 de Adesão Intercelular/genética , Células-Tronco Mesenquimais/metabolismo , Células Estromais/metabolismo , Adolescente , Adulto , Antígenos CD58/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Galectina 1/metabolismo , Perfilação da Expressão Gênica , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Ativação Linfocitária/imunologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/imunologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/citologia , Células Estromais/imunologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Adulto JovemRESUMO
We previously showed that Trypanosoma cruzi acute infection induced infertility in a great proportion of female mice, which resulted from a defect taking place before implantation. In this study, we have analyzed every step of reproduction from mating to implantation to identify the most sensitive event. Our results show that mating, ovulation, fertilization, and first division of the zygote of infected mice take place normally compared with uninfected mice, indicating that the defect occurred after the two-cell stage. In vivo development of two-cell embryos to the blastocyst stage was indeed dramatically delayed; some embryos even arrested their development before having reached the eight-cell stage while others degenerated. The effect was less pronounced when embryos were allowed to develop in vitro, indicating that the infectious context of the mother plays a role in maintaining growth retardation. The delay of embryonic development was associated with insufficient divisions of the blastomeres and led to abnormal blastocyst outgrowth that may explain implantation failure. Inhibition of cell division was correlated with the maternal parasitemia. This work clearly shows that T. cruzi infection dramatically impedes embryonic development, offering a model for further in vivo studies of embryotrophic factors produced by the oviduct of infected females.
