Степанов Алексей Вячеславович

Кандидат биологических наук


Научный сотрудник (Лаборатория биокатализа)

Эл. почта: stepanov.aleksei.v@gmail.com

Избранные публикации

  1. Stepanov A., Belyy A., Kasheverov I., Rybinets A., Dronina M., Dyachenko I., Murashev A., Knorre V., Sakharov D., Ponomarenko N., Tsetlin V., Tonevitsky A., Deyev S., Belogurov A., Gabibov A. (2016). Development of a recombinant immunotoxin for the immunotherapy of autoreactive lymphocytes expressing MOG-specific BCRs. Biotechnol. Lett. , [+]

    Myelin oligodendrocyte glycoprotein (MOG) is one of the major autoantigens in multiple sclerosis (MS), therefore selective depletion of autoreactive lymphocytes exposing MOG-specific B cell receptors (BCRs) would be beneficial in terms of MS treatment.

    ID:1524
  2. Kuzmenkov A.I., Nekrasova O.V., Kudryashova K.S., Peigneur S., Tytgat J., Stepanov A.V., Kirpichnikov M.P., Grishin E.V., Feofanov A.V., Vassilevski A.A. (2016). Fluorescent protein-scorpion toxin chimera is a convenient molecular tool for studies of potassium channels. Sci Rep 6, 33314 [+]

    Ion channels play a central role in a host of physiological and pathological processes and are the second largest target for existing drugs. There is an increasing need for reliable tools to detect and visualize particular ion channels, but existing solutions suffer from a number of limitations such as high price, poor specificity, and complicated protocols. As an alternative, we produced recombinant chimeric constructs (FP-Tx) consisting of fluorescent proteins (FP) fused with potassium channel toxins from scorpion venom (Tx). In particular, we used two FP, eGFP and TagRFP, and two Tx, OSK1 and AgTx2, to create eGFP-OSK1 and RFP-AgTx2. We show that these chimeras largely retain the high affinity of natural toxins and display selectivity to particular ion channel subtypes. FP-Tx are displaced by other potassium channel blockers and can be used as an imaging tool in ion channel ligand screening setups. We believe FP-Tx chimeras represent a new efficient molecular tool for neurobiology.

    ID:1561
  3. Lomakin Y.A., Zakharova M.Y., Stepanov A.V., Dronina M.A., Smirnov I.V., Bobik T.V., Pyrkov A.Y., Tikunova N.V., Sharanova S.N., Boitsov V.M., Vyazmin S.Y., Kabilov M.R., Tupikin A.E., Krasnov A.N., Bykova N.A., Medvedeva Y.A., Fridman M.V., Favorov A.V., Ponomarenko N.A., Dubina M.V., Boyko A.N., Vlassov V.V., Belogurov A.A. Jr, Gabibov A.G. (2014). Heavy-light chain interrelations of MS-associated immunoglobulins probed by deep sequencing and rational variation. Mol. Immunol. , [+]

    The mechanisms triggering most of autoimmune diseases are still obscure. Autoreactive B cells play a crucial role in the development of such pathologies and, in particular, production of autoantibodies of different specificities. The combination of deep-sequencing technology with functional studies of antibodies selected from highly representative immunoglobulin combinatorial libraries may provide unique information on specific features in the repertoires of autoreactive B cells. Here, we have analyzed cross-combinations of the variable regions of human immunoglobulins against the myelin basic protein (MBP) previously selected from a multiple sclerosis (MS)-related scFv phage-display library. On the other hand, we have performed deep sequencing of the sublibraries of scFvs against MBP, Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1), and myelin oligodendrocyte glycoprotein (MOG). Bioinformatics analysis of sequencing data and surface plasmon resonance (SPR) studies have shown that it is the variable fragments of antibody heavy chains that mainly determine both the affinity of antibodies to the parent autoantigen and their cross-reactivity. It is suggested that LMP1-cross-reactive anti-myelin autoantibodies contain heavy chains encoded by certain germline gene segments, which may be a hallmark of the EBV-specific B cell subpopulation involved in MS triggering.

    ID:1009