RESUMO
Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by early onset of recurrent and severe infections. The molecular defects causing CGD are heterogeneous and lead to absence, low expression, or malfunctioning of one of the phagocyte NADPH oxidase components. It is known that mutations leading to CGD reside within the genes encoding four essential components of the oxidase designated as gp91-phox (phagocyte oxidase), p22-phox, p47-phox and p67-phox. gp91- together with p22-phox form the membrane cytochrome b(558) and play an essential role in the transfer of electrons following assembly of the active oxidase with the cytoplasmic p47- and p67-phox components. In hematopoietic cells, CYBB expression (the gene encoding gp91-phox) is limited to the granulocyte and monocyte/macrophage lineages during the process of terminal differentiation. CYBB is responsive to a number of inflammatory cytokines, especially interferon-gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha). Cytokines have been also studied for activation of phagocytes respiratory burst. IFN-gamma stimulates superoxide release and is a prophylactic agent for CGD. It has been shown in vitro and in vivo to correct at least in part alterations of the oxidative metabolism, and to improve their microbicidal function. It has demonstrated clinical benefit in the majority of patients with CGD, reducing the relative risk of severe infections in 70%. In this study, we review mechanisms showing that IFN-gamma improves the splicing efficiency of CYBB gene transcripts in a particular group of CGD patients. The present article is an informative review of recent patents related to the use of interferon gamma therapy in chronic granulomatous disease.
Assuntos
Doença Granulomatosa Crônica/tratamento farmacológico , Interferon gama/uso terapêutico , HumanosRESUMO
A imunodeficiência comum variável (CVID) é uma doença caracterizada por hipogamaglobulinemia, infecções recorrentes, especialmente das vias aéreas, enfermidades auto-imunes e neoplasias. Alguns pacientes com CVID possuem diversos distúrbios do sistema imune como alterações no número e proporção de diferentes populações leucocitárias; resposta proliferativa linfocitária diminuída para antígenos e mitógenos; produção alterada de citocinas e alteração na expressão de moléculas de superfície. Neste trabalho, são discutidas várias destas alterações imunológicas procurando correlacioná-las aos achados clínicos dos pacientes e incorporar aos dados da literatura os nossos próprios achados.
Assuntos
Humanos , Linfócitos B , Imunodeficiência de Variável Comum , gama-Globulinas , Linfócitos T , Imunodeficiência de Variável ComumRESUMO
Common variable immunodeficiency (CVID) is an immunological disorder characterized by defective antibody production, recurrent infections, most notably of the respiratory tract, autoimmune phenomena and cancer. Some CVID patients may also present disturbances of the cellular immune response such as a decrease in the number and proportion of different lymphocyte populations, diminished lymphoproliferative response to mitogens and antigens, altered production of cytokines, and deficient expression of cell-surface molecules. Most Brazilian CVID patients included in this study show a decrease in T and B lymphocyte counts in the peripheral blood. Furthermore, their lymphocytes are more susceptible to apoptosis following activation than normal individuals, and they have a decrease in the expression of activation molecules like CD25, CD69, CD40L and CD70. Moreover, they show a decreased synthesis of IL-4 and IL-5 in comparison with normal individuals. The increase in susceptibility to apoptosis following activation, may also be responsible for the decrease in the expression of activation molecules and CD40L, decrease in Th2 cytokines synthesis, and in the number of T and B circulating cells. In this study we discuss some of these immunological disturbances correlating them to the patients' clinical features and comparing our patients' findings to the literature.