Formation of lipoxin B by the pure reticulocyte lipoxygenase

The pure reticulocyte lipoxygenase converts 5,15-DiHETE via a lipoxygenase reaction to 5,14,15-trihydroxy-6,8,10,12-eicosatetraenoic acid (a lipoxin B isomer) as shown by GC/MS analysis of its trimethylsilyl ether. With arachidonic acid, 15-HETE and 15-HETE methyl ester this lipoxin B isomer was also formed. The results presented here indicate that pure mammalian lipoxygenases are able to form lipoxins via sequential multiple oxygenation of arachidonic acid or its hydroxy derivatives.     

The discovery and initial optimisation of pyrrole-2-carboxamides as inhibitors of p38α MAP kinase

A novel pyrrole-2-carboxamide series of p38α inhibitors, discovered through the application of virtual screening, is presented. Following evaluation of activity, selectivity and developability properties of commercially available analogues, a synthesis program enabled rapid assessment of the series’ suitability for further lead optimisation studies.     

Safety and Immunogenicity of Boosting BCG Vaccinated Subjects with BCG: Comparison with Boosting with a New TB Vaccine,MVA85A

Objectives

To investigate the safety and immunogenicity of a booster BCG vaccination delivered intradermally in healthy, BCG vaccinated subjects and to compare with a previous clinical trial where BCG vaccinated subjects were boosted with a new TB vaccine, MVA85A.

Design

Phase I open label observational trial, in the UK. Healthy, HIV-negative, BCG vaccinated adults were recruited and vaccinated with BCG. The primary outcome was safety; the secondary outcome was cellular immune responses to antigen 85, overlapping peptides of antigen 85A and tuberculin purified protein derivative (PPD) detected by ex vivo interferon-gamma (IFN-γ) ELISpot assay and flow cytometry.

Results and Conclusions

BCG revaccination (BCG-BCG) was well tolerated, and boosting of pre-existing PPD-specific T cell responses was observed. However, when these results were compared with data from a previous clinical trial, where BCG was boosted with MVA85A (BCG-MVA85A), MVA85A induced significantly higher levels (>2-fold) of antigen 85-specific CD4+ T cells (both antigen and peptide pool responses) than boosting with BCG, up to 52 weeks post-vaccination (p = 0.009). To identify antigen 85A-specific CD8+ T cells that were not detectable by ex vivo ELISpot and flow cytometry, dendritic cells (DC) were used to amplify CD8+ T cells from PBMC samples. We observed low, but detectable levels of antigen 85A-specific CD8+ T cells producing IFNγ (1.5% of total CD8 population) in the BCG primed subjects after BCG boosting in 1 (20%) of 5 subjects. In contrast, in BCG-MVA85A vaccinated subjects, high levels of antigen 85A-specific CD8+ T cells (up to 14% total CD8 population) were observed after boosting with MVA85A, in 4 (50%) of 8 subjects evaluated.In conclusion, revaccination with BCG resulted in modest boosting of pre-existing immune responses to PPD and antigen 85, but vaccination with BCG-MVA85A induced a significantly higher response to antigen 85 and generated a higher frequency of antigen 85A-specific CD8+ T cells.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00654316","term_id":"NCT00654316"}}NCT00654316 {"type":"clinical-trial","attrs":{"text":"NCT00427830","term_id":"NCT00427830"}}NCT00427830