Rheumatoid Arthritis: Zheng X

Ichim TE, Zheng X, Suzuki M, Kubo N, Zhang X, Min LR, Beduhn ME, Riordan NH, Inman RD, Min WP. · University of Western Ontario, Departments of Surgery, Pathology, Microbiology & Immunology, 339 Windermere Road, University Hospital C9-136, London, Ontario, N6A 5A5, Canada. · Expert Opin Biol Ther. · Pubmed #18194075 No free full text.

Abstract: BACKGROUND: Immunotherapy offers the promise of antigen-specific suppression of pathological immune responses in conditions such as autoimmunity and organ transplantation. Substantial advances have been made in recent years in terms of understanding basic immunological mechanisms of autoreactivity, as well as clinically implementing immune-based therapies that are antigen nonspecific. OBJECTIVE: To provide an integrated overview of the current state of the art in terms of antigen-specific tolerance induction, as well as to predict future directions for the field. METHODS: Examples of successes and failures of antigen-specific immunotherapy were sought. Particular attention was paid to the well-established collagen II-induced model of arthritis. RESULTS/CONCLUSIONS: Previous failures of antigen-specific immunotherapy were associated with lack of identification of clinically relevant antigens, as well as inappropriate tolerogenic methodologies. The advances in proteomics combined with novel gene-specific immune modulatory techniques place today's translational researchers in a unique position to tackle the problem of antigen-specific immunotherapeutic protocols.

Zheng X, Wu SL, Hincapie M, Hancock WS. · Barnett Institute and Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA. · J Chromatogr A. · Pubmed #19215933 No free full text.

Abstract: In this study, we report a combined proteomic and peptidomic analysis of human plasma from patients with rheumatoid arthritis (RA) and controls. We used molecular weight cut-off filters (MWCO: 10kDa) to enrich low-molecular-weight (LMW) peptides from human plasma. The peptide fraction was analyzed without trypsin digestion by capillary reversed-phase high-performance liquid chromatography (HPLC) coupled to a linear ion trap-FT-MS system, which identified 771 unique peptides in the peptidome study (from 145 protein progenitors). An anti-albumin/anti-IgG column was used to remove albumin and immunoglobulin G (IgG) from the human plasma. After that, the albumin/IgG-depleted sample was fractionated into a bound fraction and an unbound fraction on a multi-lectin affinity column (M-LAC). LC-MS analysis of the corresponding tryptic digests identified 308 proteins using the M-LAC approach. Relative differences in the following protein classifications were observed in the RA human plasma samples compared with controls: structural proteins, immuno-related proteins, protease inhibitors, coagulation proteins, transport proteins and apolipoproteins. While some of these proteins/peptides have been previously reported to be associated with RA disease such as calgranulin A, B, C and C-reactive protein, several others were newly identified (such as thymosin beta4, actin, tubulin, and vimentin), which may further the understanding of the disease pathogenesis. Moreover, we have found that the peptidomic and glycoproteomic approaches were complementary and allow a more complete picture of the human plasma proteome which can be valuable in studies of disease etiology.

Popov I, Li M, Zheng X, San H, Zhang X, Ichim TE, Suzuki M, Feng B, Vladau C, Zhong R, Garcia B, Strejan G, Inman RD, Min WP. · Department of Surgery, London Health Science Centre, London, Canada. · Arthritis Res Ther. · Pubmed #16911769 links to  free full text

Abstract: Conventional treatments for autoimmune diseases have relied heavily on nonspecific immune suppressants, which possess a variety of adverse effects without inhibiting the autoimmune process in a specific manner. In the present study we demonstrate the effectiveness of antigen-specific, maturation-resistant, tolerogenic dendritic cells (DC) in suppressing collagen-induced arthritis, a murine model of rheumatoid arthritis. Treatment of DC progenitors with the NF-kappaB inhibiting agent LF 15-0195 (LF) resulted in a population of tolerogenic DC that are characterized by low expression of MHC class II, CD40, and CD86 molecules, as well as by poor allostimulatory capacity in a mixed leukocyte reaction. Administering LF-treated DC pulsed with keyhole limpet hemocyanin antigen to naïve mice resulted hyporesponsiveness specific for this antigen. Furthermore, administration of LF-treated DC to mice with collagen-induced arthritis resulted in an improved clinical score, in an inhibited antigen-specific T-cell response, and in reduced antibody response to the collagen. The efficacy of LF-treated DC in preventing arthritis was substantiated by histological examination, which revealed a significant decrease in inflammatory cell infiltration in the joints. In conclusion, we demonstrate that in vitro-generated antigen-specific immature DC may have important potential as a tolerogenic vaccine for the treatment of autoimmune arthritis.