Defining TNF-α and IL-1β induced nascent proteins: combining bio-orthogonal non-canonical amino acid tagging and proteomics.

An impediment in the development of new therapeutic strategies for chronic inflammatory diseases is the limited understanding of underlying molecular mechanisms. The objective of this study was to identify newly synthesized (nascent) proteins induced by critical inflammatory cytokines TNF-α and IL-1β in human monocytic THP-1 cells. We optimized methods to combine two different approaches, bio-orthogonal non-canonical amino acid tagging (BONCAT) along with proteomics using isobaric tags (iTRAQ).

Modulation of interleukin-1β-induced inflammatory responses by a synthetic cationic innate defence regulator peptide, IDR-1002, in synovial fibroblasts.

Introduction: Innate defence regulator (IDR) peptides are synthetic cationic peptides, variants of naturally occurring innate immune effector molecules known as host defence peptides. IDR peptides were recently demonstrated to limit infection-associated inflammation selectively without compromising host innate immune functions. This study examined the impact of a 12-amino acid IDR peptide, IDR-1002, in pro-inflammatory cytokine interleukin (IL)-1β-induced responses in synovial fibroblasts, a critical cell type in the pathogenesis of inflammatory arthritis.

Intracellular receptor for human host defense peptide LL-37 in monocytes.

The human cationic host defense peptide LL-37 has a broad range of immunomodulatory, anti-infective functions. A synthetic innate defense regulator peptide, innate defense regulator 1 (IDR-1), based conceptually on LL-37, was recently shown to selectively modulate innate immunity to protect against a wide range of bacterial infections. Using advanced proteomic techniques, ELISA, and Western blotting procedures, GAPDH was identified as a direct binding partner for LL-37 in monocytes.