Immuuntolerantsi häirumine, mille üheks väljundiks on antikehade teke organismile omaste biomolekulide vastu, on oluline patogeneetiline mehhanism mitmete laialdaselt levinud haiguste puhul ja seetõttu on autoantikehade määramine kujunenud oluliseks diagnostiliseks vahendiks. Artiklis on käsitletud autoantikehade esinemise olulisust haiguste tekke ja kulu prognoosimisel. Kuigi sellekohane info on veel üsna napp, on selge, et organismi immuunstaatuse muutus eelneb aastaid haiguse ilmnemisele ning autoimmuunset komponenti sisaldava haiguse kulg ja prognoos on seotud patsiendil esinevate kindlate autoantikehadega. Sellest tulenevalt võime loota, et organismi immuunstaatuse uurimine, eriti aga autoantikehade spektri iseloomustamine, on tulevikus geneetilise info analüüsimise kõrval üks täppismeditsiini olulisemaid tööriistu.
Antibody repertoire profiling with mimotope arrays
Pashova, Shina; Schneider, Christoph; von Gunten, Stephan; Pashov, Anastas
Large-scale profiling and monitoring of antibody repertoires is possible through next generation sequencing (NGS), phage display libraries and microarrays. These methods can be combined in a pipeline, which ultimately maps the antibody reactivities onto defined arrays of structures – peptides or carbohydrates. The arrays can help analyze the individual specificities or can be used as complex patterns. In any case, the targets recognized should formally be considered mimotopes unless they are proven to be epitopes driving the antibody synthesis. Here, the advantages and disadvantages of the major profiling techniques as well as their current and future application in disease prediction and vaccination are discussed.
Optimised ‘on demand’ protein arraying from DNA by cell free expression with the ‘DNA to Protein Array’ (DAPA) technology
Schmidt, Ronny; Cook, Elizabeth A.; Kastelic, Damjana; Taussig, Michael J.; Stoevesandt, Oda
We have previously described a protein arraying process based on cell free expression from DNA template arrays (DNA Array to Protein Array, DAPA). Here, we have investigated the influence of different array support coatings (Ni-NTA, Epoxy, 3D-Epoxy and Polyethylene glycol methacrylate (PEGMA)). Their optimal combination yields an increased amount of detected protein and an optimised spot morphology on the resulting protein array compared to the previously published protocol. The specificity of protein capture was improved using a tag-specific capture antibody on a protein repellent surface coating. The conditions for protein expression were optimised to yield the maximum amount of protein or the best detection results using specific monoclonal antibodies or a scaffold binder against the expressed targets. The optimised DAPA system was able to increase by threefold the expression of a representative model protein while conserving recognition by a specific antibody. The amount of expressed protein in DAPA was comparable to those of classically spotted protein arrays. Reaction conditions can be tailored to suit the application of interest. Biological significance: DAPA represents a cost effective, easy and convenient way of producing protein arrays on demand. The reported work is expected to facilitate the application of DAPA for personalized medicine and screening purposes.
Purification of High-Complexity Peptide Microarrays by Spatially Resolved Array Transfer to Gold-Coated Membranes
Schirwitz, Christopher; Loeffler, Felix F.; Felgenhauer, Thomas; Stadler, Volker; Nesterov-Mueller, Alexander; Dahint, Reiner; Breitling, Frank; Bischoff, F. Ralf
A method for the one-step purification of high-complexity peptide microarrays is presented. The entire peptide library is transferred from the synthesis support to a gold coated polyvinylidenfluoride (PVDF) membrane, whereby only full-length peptides covalently couple to the receptor membrane via an N-terminally added cysteine. Highly resolved peptide transfer and purification of up to 10 000 features per cm2 is demonstrated.
Single-Molecule Detection on a Protein-Array Assay Platform for the Exposure of a Tuberculosis Antigen
Arrays promise to advance biology through parallel screening for binding partners. We show the combinatorial in situ synthesis of 40,000 peptide spots per square centimeter on a microchip. Our variant Merrifield synthesis immobilizes activated amino acids as monomers within particles, which are successively attracted by electric fields generated on each pixel electrode of the chip. With all different amino acids addressed, particles are melted at once to initiate coupling. Repetitive coupling cycles should allow for the translation of whole proteomes into arrays of overlapping peptides that could be used for proteome research and antibody profiling.
