Abstract
We investigated expression of costimulatory molecules BB-1, B7-1 (CD80), B7-2 (CD86), and their counter-receptors CD28 and CTLA-4 (CD152) in muscle biopsy specimens of patients with scleroderma-polymyositis overlap syndrome (SSc-PM), primary polymyositis (PM), and other related diseases to examine whether the muscle fibers in patients with SSc-PM behave as antigen-presenting cells (APCs). The major histocompatibility (MHC) class II-positive muscle fibers of SSc-PM patients reacted with monoclonal antibodies (mAb) against BB-1 but not against B7-1 or B7-2. The CD4+ T cells expressed the counter-receptors CD28 and CTLA-4, and bound with the BB-1-positive muscle fibers in cell-to-cell contact. Our findings show that muscle fibers in patients with SSc-PM function as "professional" APCs in a way distinct from muscle fibers in patients with primary PM.
MeSH terms
-
Abatacept
-
Adult
-
Aged
-
Antigens, CD
-
Antigens, Differentiation / genetics
-
Antigens, Differentiation / metabolism
-
Antigens, Differentiation, B-Lymphocyte / genetics
-
Antigens, Differentiation, B-Lymphocyte / metabolism
-
B7-1 Antigen / genetics
-
B7-1 Antigen / metabolism*
-
Bacterial Proteins / metabolism
-
Biopsy
-
CD28 Antigens / genetics
-
CD28 Antigens / metabolism*
-
CD4 Antigens / genetics
-
CD4 Antigens / immunology
-
CD8 Antigens / genetics
-
CD8 Antigens / metabolism
-
CTLA-4 Antigen
-
Female
-
Histocompatibility Antigens Class II / genetics
-
Histocompatibility Antigens Class II / metabolism
-
Humans
-
Immunoconjugates*
-
Immunohistochemistry
-
Middle Aged
-
Polymyositis / complications
-
Polymyositis / genetics
-
Polymyositis / metabolism*
-
RNA, Messenger / metabolism
-
Reverse Transcriptase Polymerase Chain Reaction
-
Scleroderma, Systemic / complications
-
Scleroderma, Systemic / genetics
-
Scleroderma, Systemic / metabolism*
Substances
-
Antigens, CD
-
Antigens, Differentiation
-
Antigens, Differentiation, B-Lymphocyte
-
B7-1 Antigen
-
Bacterial Proteins
-
CD28 Antigens
-
CD4 Antigens
-
CD8 Antigens
-
CTLA-4 Antigen
-
CTLA4 protein, human
-
Histocompatibility Antigens Class II
-
Immunoconjugates
-
Map protein, Staphylococcus aureus
-
RNA, Messenger
-
invariant chain
-
Abatacept