Skin T cell proliferative response to M protein and other cell wall and membrane proteins of group A streptococci in chronic plaque psoriasis

Citation
Bs. Baker et al., Skin T cell proliferative response to M protein and other cell wall and membrane proteins of group A streptococci in chronic plaque psoriasis, CLIN EXP IM, 124(3), 2001, pp. 516-521
Citations number
25
Categorie Soggetti
Immunology
Journal title
CLINICAL AND EXPERIMENTAL IMMUNOLOGY
ISSN journal
00099104 → ACNP
Volume
124
Issue
3
Year of publication
2001
Pages
516 - 521
Database
ISI
SICI code
0009-9104(200106)124:3<516:STCPRT>2.0.ZU;2-A
Abstract
To determine and compare the T cell response to M protein and other group A streptococcal (GAS) antigens, T cell lines (TCL) were cultured from the le sional skin of 33 psoriatic patients and 17 disease controls. GAS-reactive skin TCL were tested in proliferation assays with recombinant M6 protein, a nd extracts of cell wall and membrane from type M6 GAS and its correspondin g M gene deletion mutant. Initially, GAS-reactive skin TCL were obtained fr om 16 of 25 (64%) psoriasis, and from seven of 17 (41%) control patients. E leven psoriatic and four control GAS-reactive TCL proliferated to M6 cell w all extract, whereas all the TCL from both groups responded to the extract of M6 membrane proteins. This difference in response to the two extracts wa s significant for both groups of patients (psoriasis, P = 0.0335, controls, P = 0.0156). GAS-reactive TCL from a further eight psoriasis patients show ed no difference in response to cell wall extract from M6 GAS (containing t he M protein minus its C-terminus) compared to that of its corresponding M gene deletion mutant. Furthermore, GAS-reactive TCL did not proliferate to recombinant M6 protein. However, a small, but significant reduction in prol iferation by the eight psoriatic GAS-reactive TCL to the M-negative (lackin g the M protein C-terminus) compared to M6-positive membrane extract was ob served (P = 0.01). These findings suggest that GAS-reactive T cells in skin lesions of chronic plaque psoriasis proliferate to streptococcal membrane and, to a lesser extent, cell wall proteins. However, psoriatic skin T cell s do not recognize cell wall M protein.