A combination of two Brugia malayi filarial vaccine candidate antigens (BmALT-2 and BmVAH) enhances immune responses and protection in jirds

In this study filarial recombinant protein or DNA vaccine constructs encoding BmALT-2 and BmVAH as single or as cocktail antigens were evaluated. Male jirds were immunized intramuscularly with DNA vaccine constructs or were immunized intraperitoneally with protein vaccine. The single and bicistronic DNA constructs induced substantial interferon-γ responses in spleen cells; antigen-specific responses were higher following immunization with the bicistronic cocktail construct and evoked a significant protective response of 57% in jirds challenged with Brugia malayi that was similar in the antibody-dependent cellular cytotoxicity (ADCC) assay and micropore chamber experiment. The cocktail protein vaccines induced a mixture of IgG2a (Th1) and IgG1 (Th2) responses with 80% protective response when challenged with B. malayi infective larvae. However, the single protein vaccine rALT-2 induced Th2 (IgG1/IgG3) with a 70% protective response and rVAH induced Th1 (IgG2a) with a lower proliferative response with 60% protection following challenge with B. malayi infective larvae. These results suggest that filarial cocktail protein vaccines are able to elicit substantial immune and protective responses when compared with single antigen vaccination in suitably vaccinated jirds.     

The sites for catalysis and activation of ribulosebisphosphate carboxylase share a common domain

The complexation of ribulosebiphosphate carboxylase with CO2, Mg2+, and carboxyarabinitol bisphosphate (CABP) to produce the quaternary enzyme-carbamate-Mg2+-CABP complex closely mimics the formation of the catalytically competent enzyme-carbamate-Mg2+-3-keto-CABP form during enzymatic catalysis. Quaternary complexes were prepared with various metals (Mg2+, Cd2+, Mn2+, Co2+, and Ni2+) and with specifically 13C-enriched ligands. 31P and 13C NMR studies of these complexes demonstrate that the activator CO2 site (carbamate site), the metal binding site, and the substrate binding site are contiguous. It follows that both the carboxylase and oxygenase activities of this bifunctional enzyme are influenced by the structures of the catalytic and activation sites.     

Rapid resolution of phenylthiohydantoin amino acids by thin-layer chromatography on silica gel plates impregnated with transition metal ions

The resolution of a 15-component mixture of phenylthiohydantoin (PTH) amino acids using metal ion impregnated silica gel plates is reported. The spots are located by exposing the chromatograms to an iodine chamber. The method provides a rapid, simple, and less expensive chromatographic system, provides resolution for certain difficult combinations, and leaves the PTH amino acids unaltered chemically.     

Central Nervous System Pathology Progresses Independently of KC and CXCR2 in Globoid-Cell Leukodystrophy

Globoid-cell Leukodystrophy (GLD; Krabbe’s disease) is a rapidly progressing inherited demyelinating disease caused by a deficiency of the lysosomal enzyme Galactosylceramidase (GALC). Deficiency of GALC leads to altered catabolism of galactosylceramide and the cytotoxic lipid, galactosylsphingosine (psychosine). This leads to a rapidly progressive fatal disease with spasticity, cognitive disability and seizures. The murine model of GLD (Twitcher; GALC−/−) lacks the same enzyme and has similar clinical features. The deficiency of GALC leads to oligodendrocyte death, profound neuroinflammation, and the influx of activated macrophages into the CNS. We showed previously that keratinocyte chemoattractant factor (KC) is highly elevated in the CNS of untreated Twitcher mice and significantly decreases after receiving a relatively effective therapy (bone marrow transplantation combined with gene therapy). The action of KC is mediated through the CXCR2 receptor and is a potent chemoattractant for macrophages and microglia. KC is also involved in oligodendrocyte migration and proliferation. Based on the commonalities between the disease presentation and the functions of KC, we hypothesized that KC and/or CXCR2 contribute to the pathogenesis of GLD. Interestingly, the course of the disease is not significantly altered in KC- or CXCR2-deficient Twitcher mice. There is also no alteration in inflammation or demyelination patterns in these mice. Furthermore, transplantation of CXCR2-deficient bone marrow does not alter the progression of the disease as it does in other models of demyelination. This study highlights the role of multiple redundant cytokines and growth factors in the pathogenesis of GLD.