Multiplexed Protein Profiling
In the department of immunotechnology at Lund University in Sweden, associate professor, Christer Wingren, Ph.D., and colleagues have developed a set of recombinant antibody microarray technology platforms for high-throughput, multiplexed protein profiling of crude, nonfractionated samples.
Recently, the team developed the Global Proteome Survey (GPS), for the profiling of complex nonfractionated proteomes. Combining affinity proteomics with mass spec, the technology can probe the whole human proteome in the hunt for disease biomarkers, with a sensitivity sufficient to capture even low-abundance protein analytes down to the picogram/mL range, Dr. Wingren said.
The Lund University technology does not adhere to the one-antibody-one-target approach. “Instead, we have defined a set of peptide motifs of four to six amino acids long, each of which is present in 5–100 different proteins,” Dr. Wingren continued. “The captured antibodies for these motifs, termed context-independent-motif-specific antibodies, are recombinant, single-chain Fv antibody fragments, designed specifically to survive in the assay conditions of a microarray.
“By designing just 200 antibodies that bind to 50 different motifs distributed among different proteins, we can potentially target approximately half of the nonredundant human proteome,” he added.
The overall process involves digesting a biological sample and exposing it to the chip-immobilized antibodies to capture the motif-containing peptides, which can then be enriched and detected using MS. According to Dr. Wingren, such motif-specific antibodies are potentially applicable to any proteome in any species and are not biased toward either abundant proteins or those of particular classes.
The potential utility of GPS led to the establishment of Immunovia by investigators from the department of immunotechnology and CREATE Health, Lund University’s Center for Translational Cancer Research. Immunovia will facilitate the commercialization of human antibodies and biomarkers, primarily for cancer diagnosis and therapy.
“This new technology will be used as a discovery tool in the quest for novel biomarkers, strengthening ongoing biomarker discovery efforts using conventional antibody microarrays,” Dr. Wingren explained. “Our research has already led to the identification of new biomarker signatures, some of which are currently at the validation stage. This is something we believe hasn’t been accomplished using an antibody microarray-based approach before.”