Stronger Proliferative Response to Membrane Versus Cell‐Wall Streptococcal Proteins by Peripheral Blood T Cells in Chronic Plaque Psoriasis

• Published in: Scandinavian journal of immunology 2001-12, Vol.54 (6), p.619-625
• Main Authors: Baker, B. S., Brown, D., Fischetti, V. A., Ovigne, J.‐M., Porter, W., Powles, A., Fry, L.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; AM protein; Antigen Presentation; Antigens, Bacterial; Bacterial Outer Membrane Proteins - immunology; Bacterial Proteins - immunology; Carrier Proteins - immunology; Case-Control Studies; Cell Division; Cell Wall - immunology; Chronic Disease; Female; Humans; In Vitro Techniques; Lymphocyte Activation; M gene; M6 protein; Male; Membrane Proteins - immunology; Middle Aged; Psoriasis - immunology; Streptococcus pyogenes; Streptococcus pyogenes - immunology; T-Lymphocytes - immunology; T-Lymphocytes - pathology
• ISSN: 0300-9475; 1365-3083
• DOI: 10.1046/j.1365-3083.2001.01009.x

Proliferative responses of peripheral blood mononuclear cells (PBMC) to group A streptococcal (GAS) antigens have been studied in 24 patients with psoriasis and 15 disease controls. Extracts of cell wall (including M protein) from types M4 and M12 GAS, recombinant M6 protein, and both cell‐wall and cell‐membrane extracts from type M6 (M6+) GAS and its corresponding M gene deletion mutant (M6‐) were tested. PBMC from psoriatic patients proliferated more strongly to cell‐wall extracts from M12 versus M4 (P = 0.0348), and to M6+ versus M6‐ (P = 0.0019) GAS with, in most cases, moderate proliferation to recombinant M6 protein. The psoriatic response to M12 cell wall was significantly increased compared to the controls (P = 0.0032). In psoriatics, M6+ membrane extracts induced a markedly greater proliferation than those of cell wall (P = 0.0002); responses to M6+ (P = 0.0039) and M6‐ (P = 0.0114) membrane extracts were higher than those of the control PBMC. Both groups showed a decreased response to the M6‐ versus M6+ membrane extracts (P = 0.0030; P= 0.0181, respectively). This study has demonstrated that patients with psoriasis have a heightened circulating T‐cell response to cell wall M protein and to non‐M proteins present on the cell wall and membrane of GAS.