Assuntos
Anemia de Diamond-Blackfan/genética , Mutação , Criança , Humanos , Masculino , Linhagem , Fenótipo , Proteínas Ribossômicas/genéticaRESUMO
We describe a young patient with typical neurofibromatosis type 1 on the basis of a mutation in the NF1 gene, who was diagnosed with a unilateral vestibular schwannoma caused by a somatic mutation in the NF2 gene. This combination has not been described before. This report highlights the requirement for ongoing surveillance regarding other manifestations of neurofibromatosis type 2 in such patients, as mosaicism cannot be ruled out. In addition to the NF1 mutation, the NF2 mutation should be considered in such cases if pre-implantation genetic diagnosis in undertaken.
Assuntos
Genes da Neurofibromatose 1 , Genes da Neurofibromatose 2 , Neurofibromatose 1/genética , Neuroma Acústico/genética , Adulto , Análise Mutacional de DNA , Humanos , Masculino , MutaçãoRESUMO
Although the importance of the macrophage complement receptor immunoglobulin (CRIg) in the phagocytosis of complement opsonized bacteria and in inflammation has been established, the regulation of CRIg expression remains undefined. Because cellular activation during inflammation leads to the release of arachidonate, a stimulator of leukocyte function, we sought to determine whether arachidonate regulates CRIg expression. Adding arachidonate to maturing human macrophages and to prematured CRIg(+) macrophages caused a significant decrease in the expression of cell-surface CRIg and CRIg mRNA. This effect was independent of the metabolism of arachidonate via the cyclooxygenase and lipoxygenase pathways, because it was not inhibited by the nonsteroidal anti-inflammatory drugs indomethacin and nordihydroguaiaretic acid. Studies with specific pharmacological inhibitors of arachidonate-mediated signaling pathways showed that protein kinase C was involved. Administration of dexamethasone to macrophages caused an increase in CRIg expression. Studies with proinflammatory and immunosuppressive cytokines showed that IL-10 increased, but interferon-γ, IL-4, and transforming growth factor-ß1 decreased CRIg expression on macrophages. This down- and up-regulation of CRIg expression was reflected in a decrease and increase, respectively, in the phagocytosis of complement opsonized Candida albicans. These data suggest that a unique inflammatory mediator network regulates CRIg expression and point to a mechanism by which arachidonate and dexamethasone have reciprocal effects on inflammation.
