Natural immune response key to new vaccines
The leaps and bounds made in genomics are about to propel the fight against human diseases like malaria to a level previously not thought possible. As part of this movement, the EU-funded project Microbearray has directed its resources towards the identification of surface and secreted proteins as well as possible endotoxins from a selection of clinically important pathogens. Microbearray researchers collected a repertoire of proteins to produce array slides of recombinant proteins from microbes including coronavirus species, three bacteria that cause pneumonia (including that responsible for Legionnaire's disease) and the malarial agent Plasmodium falciparum (P. falciparum). The next step was to compare the arrays of microbial proteins with serum proteins from individuals previously exposed to the relevant diseases. This way, the project scientists aimed to identify both diagnostic markers and recombinant proteins suitable for vaccine development. Alongside this ambitious objective, the team developed a technological platform to maximise the potential use of the microarrays. The overall kit included a microarray reader, high-throughput protein production and tools to capture and synthesise protein as well as essential software. As regards malaria, around 200 antibody profiles were analysed from children that showed different levels of immunity. Based on an 18 recombinant antigen that showed the most promise, the scientists found an unprecedented variation in reaction of individual antibodies to malaria antigens. Project findings suggest that immunity to malaria is down to antibody recognition of many rather than individual antigens. Aided by Microbearray technological achievements, analysis of hundreds of combinations of antigen-antibody response should identify specific combinations that confer protective immunity. Serum profiling against microbial antigen profiles can be applied beyond the scope of the malaria parasite to any pathogen with a complete genomic sequence. Moreover, Microbearray developments promise to lower the price of microarray technology increasing availability to smaller commercial enterprises.