Quantitative Analysis of Complement Membrane Attack Complex Proteins Associated with Extracellular Vesicles.

Extracellular vesicles (EVs) represent a universal mechanism of intercellular communication in normal and pathological conditions. There are reports showing the presence of complement proteins in EV preparations, specifically those that can form a membrane attack complex (MAC). In the present work, we have used a quantitative mass spectrometry method that allows for the measurement of multiple targeted proteins in one experimental run.

Isolation protocols and mitochondrial content for plasma extracellular vesicles.

Mitochondrial content has been reported outside of cells either within extracellular vesicles (EVs) or as free mitochondria. Mitochondrial EVs can potentially play multiple physiological and pathophysiological roles. To understand their functions, isolation protocols to separate mitochondrial EVs from other mitochondrial content need to be established.

Quantitative proteomic analysis for evaluating affinity isolation of extracellular vesicles.

Absolute quantification with mass spectrometry and isotope labeled internal standards has found broad applications in biomedical research. In the present research, it was used for developing and evaluating a new affinity-based approach to isolate extracellular vesicles (EVs) from human plasma. First, a phage display peptide library was screened against EVs as a bait and absolute quantification of multiple proteins helped to select the best bait available.

Quantitative Proteomic Analysis of Biogenesis-Based Classification for Extracellular Vesicles.

Extracellular vesicles (EVs) are traditionally divided into two major groups: (i) large vesicles originating from plasma membrane and called microvesicles, and (ii) small vesicles originating from the endoplasmic membrane and called exosomes. However, it is increasingly clear that the actual composition of a particular EV preparation cannot be adequately described with these two simple terms and is much more complex. Since the cell membrane origin of EVs predetermines their biological functions, the understanding of EV biogenesis is important for accurate interpretation of observed results.

A New Approach to Assess mAb Aggregation.

A proof of concept for new methodology to detect and potentially quantify mAb aggregation is presented. Assay development included using an aggregated mAb as bait for screening of a phage display peptide library and identifying those peptides with random sequence which can recognize mAb aggregates. The selected peptides can be used for developing homogeneous quantitative methods to assess mAb aggregation.