APVV-16-0452

Principal Investigator: Vladimír Leksa

Principal Investigator (BRC SAS): Alexandra Zahradníková jr.

Duration: July 2017 – June 2021
Coordinating Organization: Institute of Molecular Biology SAS, Bratislava

Annotation:

Plasminogen system is one of the major proteolytic pathways. It is harnessed in many physiological processes, particularly in immune responses. The overall objective of the project is to delineate novel molecular mechanisms that control plasminogen activation in both adaptive and innate immune responses, namely in T cell migration, cytokine activation and homeostasis maintenance by macrophages. The project stems not only from our published data but also from our recent unpublished discoveries and solid preliminary results. Specific goals of the project are not mutually exclusive; there is substantial integration not only at the level of underlying cellular and molecular mechanisms and targets, but also at the level of experimental approaches, tools and devices. The major deliverables of the project will not only include deeper understanding of molecular mechanisms underlying plasminogen activation and characterization of immune cells employing these mechanisms, namely subsets of T cells and macrophages; but also novel molecular tools to pharmacologically modulate the imbalanced plasminogen activation which is associated with many human pathologies, such as chronic inflammatory diseases or cancer. The project achievements will be definitely of interest for scientists in basic research, but also for medical doctors and pharmacological companies.

Keywords:

adaptive immunity, innate immunity, pericellular proteolysis, cell migration, TGF-beta, efferocytosis, T cells, macrophages, mannose 6-phosphate/insulin-like growth factor 2 receptor – M6P/IGF2R, urokinase-type plasminogen activator receptor uPAR, cell subset

Objectives:

Major aim #1: Adaptive immune system – study of plasminogen system in T cell functions: In this project part, we want:
(i) to examine whether the M6P/IGF2R-uPAR positive T cell subset employs this complex for controlling T cell migration and/or activation of latent TGF-beta;
(ii) to characterize this M6P/IGF2R-uPAR positive T cell subset in detail;
(iii) to provide molecular tools for pharmacological modulation of these processes.

Specific objectives:
1a) Optimization of specific peptides and antibodies
1b) Generation and characterization of specific cell lines
1c) Study the role of M6P/IGF2R and uPAR in T cell migration
1d) Study the role of M6P/IGF2R and uPAR in activation of latent TGF-beta
1e) Study of regulation of the M6P/IGF2R-uPAR complex and associated partners – Phenotyping and functional characterization of the M6P/IGF2R-uPAR double positive T cell subset

Major aim #2: Innate immune system – study of plasminogen system in efferocytosis by macrophages: In this part of the project, we will:
(i) in detail depict the molecular machinery of the plasminogen-dependent efferocytosis;
(ii) characterize the physiological relevance of this mechanism and the corresponding macrophage subset;
(iii) produce molecular tools appropriate for pharmacological modulation of efferocytosis.

Specific objectives:
2a) Identification of the plasminogen receptor(s) on apoptotic cells
2b) M6P/IGF2R expression profiling in macrophage differentiation – functional characterization of the M6P/IGF2Rpositive macrophage subset
2c) Characterization of molecular determinants of plasminogen binding to lactoferrin
2d) In vitro modulation of efferocytosis via M6P/IGF2R
2e) Identification and study of M6 /IGF2R’s, u AR’s and plasminogen’s partners in macrophages

Publications: