Glycomics

In spite of the recent success of biological drugs and the current boom in biosimilar development, a comprehensive knowledge in the bioanalytical and corresponding translational regulatory aspects of this emerging field is quite often lacking and lagging behind. Protein therapeutics, especially monoclonal antibodies (mAb), are the fastest growing class of biologics. More than 20 mAbs have already been approved and hundreds are in the pipeline of clinical trials for various therapeutic indications including oncology, inflammatory diseases, organ transplantation, cardiology, viral infection, allergy, tissue growth and repair. Monoclonal antibodies are highly complex molecules with complicated higher order structure, subject to post-translational modifications, such as glycosylation. As a matter of fact, the biological effectiveness of mAbs, such as their ability to invoke antibody dependent cellular cytotoxicity (ADCC), is dependent on their receptor binding characteristics, which is a function of their glycosylation. Therefore, manipulation of the glycosylation of recombinant monoclonal antibodies to elicit optimized therapeutic effector functions represents an important area in the biopharmaceutical field. Thus, the production of mAb batches with reproducible quality and clinical efficacy poses a significant challenge that can only be met by careful process development and manufacturing control by state of the art orthogonal analytical methods, especially for the characterization of the structural complexity and diversity of their glycosylation, including positional and linkage isomers, core fucosylation and the potentially immunogenic structures of N-glycolylneuraminic acid (Neu5Gc) and a1-3 bound galactose residues. Structural determination of glycans is a difficult task mainly due to the large diversity of sugar structures found in nature, the complex biosynthetic pathway variations and the very close physical and chemical similarities of oligosaccharides. Capillary electrophoresis with laser induced fluorescence detection (LIF) is an excellent tool to analyze fluorescently labeled glycans including the determination of their positional and linkage isomers. Novel analysis methods for glycoprotein sizing/subunit determination and comprehensive glycosylation analysis including glycan profiling, monosaccharide composition analysis and carbohydrate sequencing techniques as well as sialylation degree determination are all developed in the Laboratory.
  
  
  
Biomarker Discovery

Identification of quantitative and/or qualitative protein expression differences and characterization of specific proteomes (e.g., cancer cell proteome) will advance clinical diagnostics and drug discovery. Up and down-regulation and the appearance or disappearance of hundreds and sometimes even thousands of proteins can be encountered in cellular systems subjected to changes in physiological conditions, such as cancer and other diseases. This project aims to develop novel proteomics tools with the main emphasis on mapping diseased cell proteomes and discover new surrogate biological markers (biomarkers). Orthogonal and distinctly unrelated separation techniques such as multidimensional electrophoresis and chromatographic methods provide excellent resolving power, while their miniaturization enables rapid analysis times. Advanced bioinformatics tools are used for quantification and comparison of individual proteins and up and down-regulation domains between samples, e.g., cancer cells vs. normal cells, anticancer drug treated cells vs. non-treated cells, etc. Sophisticated data mining approaches (bioinformatics) are applied to find biomarkers of clinical interest.
  
  
  
Miniaturization

Interdisciplinary science and technologies have converged in the last few years to create exciting challenges and opportunities, which involve novel, integrated microfabricated analytical systems facilitating high throughput biomedical applications. These new devices are referred to as Lab-on-a-Chip or Micro Total Analysis Systems (uTAS) and their development involves both established and evolving technologies including microlithography, micromachining, micro-electromechanical systems (MEMS) technology, microfluidics and nanotechnology. Main applications for this novel "synergized" technology will include rapid and high throughput bioseparations (genome, proteome and metabolome analysis) for the biomedical and biotechnology fields; high throughput laboratory analysis (particularly DNA and immunology related) for the medical diagnostic field; drug discovery, combinatorial chemistry and process control for the pharmaceutical industry; and portable/hand-held analytical instrumentation for the point of care clinical device, environmental and bio-weapons/defense sector. Microfabricated devices have many advantages, such as low reagent consumption, small (nanoliter) sample requirement, as well as, readiness for system integration and high throughput parallel processing, consequently leading to reduction in overall processing/analysis time. Microchannel networks /reservoir structures are fabricated into appropriate wafer materials (glass, plastic, fused silica, etc.) using conventional techniques of the microelectronics industry. Microfabricated channels in silica wafers act like a network of capillaries and can support both electric field (zone electrophoresis, micellar electrokinetic chromatography, gel electrophoresis, isoeletric focusing, isotachophoresis and electrochromatography) and pressure mediated (capillary liquid chromatography) techniques. Parallel setup, in the way of using microchannel arrays etched into the glass wafer, ensures high throughput processing. In addition to separation channels, structures such as mixing compartments, reaction chambers (e.g., PCR), incubation and fraction collection units, etc., can be fabricated into a single microdevice (system integration).