The Role of Thioredoxin Reductases in Brain Development

The thioredoxin-dependent system is an essential regulator of cellular redox balance. Since oxidative stress has been linked with neurodegenerative disease, we studied the roles of thioredoxin reductases in brain using mice with nervous system (NS)-specific deletion of cytosolic (Txnrd1) and mitochondrial (Txnrd2) thioredoxin reductase. While NS-specific Txnrd2 null mice develop normally, mice lacking Txnrd1 in the NS were significantly smaller and displayed ataxia and tremor. A striking patterned cerebellar hypoplasia was observed. Proliferation of the external granular layer (EGL) was strongly reduced and fissure formation and laminar organisation of the cerebellar cortex was impaired in the rostral portion of the cerebellum. Purkinje cells were ectopically located and their dendrites stunted. The Bergmann glial network was disorganized and showed a pronounced reduction in fiber strength. Cerebellar hypoplasia did not result from increased apoptosis, but from decreased proliferation of granule cell precursors within the EGL. Of note, neuron-specific inactivation of Txnrd1 did not result in cerebellar hypoplasia, suggesting a vital role for Txnrd1 in Bergmann glia or neuronal precursor cells

Novel expression systems for vaccine production

Initially, subunit vaccines were based on toxins purified from culture supernatants of host organisms. The increase in the use of genomics-based approaches to subunit vaccine development has facilitated the identification of several new candidates. This chapter reviews new systems, and focuses on plants that are being developed in an attempt to address several of the aforementioned concerns. The transgenic approach is used for producing proteins in growing plants and plant cell cultures via conventional fermentation. Another approach that is most frequently used with plant viruses is based on fusing known target peptide epitopes to the viral coat protein (CP) to obtain virus-like particles (VLPs) that mimic native viruses and present the epitopes on their surfaces, but are devoid of infectious genetic material. The launch vector technology lends itself to the creation of production modules with predetermined capacity, and by simply adding more modules, manufacturing capacity can be rapidly increased