title: Sézary T-cell activating factor is a Chlamydia pneumoniae-associated protein.
abstract: We previously identified a protein that was stimulatory for malignant Sézary T cells, termed Sézary T-cell activating factor (SAF). However, the identity of this protein has not been fully elucidated, nor has it's role been determined in the pathogenesis of cutaneous T-cell lymphoma (CTCL). The basis for epidermotropism and proliferation of malignant cells in the skin of patients with CTCL is unknown. Using a monoclonal antibody inhibitory for SAF activity, we demonstrated that SAF is present in the skin of 16 of 27 samples from patients with mycosis fungoides, the predominant form of CTCL. In this report, the SAF determinant is demonstrated to be associated with Chlamydia pneumoniae bacteria by immunohistochemistry, immunoelectron microscopy, and culture analysis. Reactivity of antibodies against an outer membrane protein of C. pneumoniae or against the lipopolysaccharide of Chlamydiae spp. demonstrated that these determinants are coexpressed in 90% of the SAF-positive samples. We confirmed the presence of C. pneumoniae DNA and RNA in the skin by PCR and reverse transcription-PCR and by sequence analysis of the PCR products. The expression of the C. pneumoniae antigens and SAF appears to be associated with active disease in that C. pneumoniae antigens were absent or greatly diminished in the skin of three patients examined after Psoralen and long-wave UVA radiation treatment. Our results suggest that SAF is a Chlamydia-associated protein and that further investigation is warranted to determine whether SAF and C. pneumoniae play a role in the pathogenesis of CTCL.
authors.affiliation: Departments of Dermatology, Medical College of Pennsylvania and Hahnemann University, Philadelphia, Pennsylvania 19102-1192, USA.
authors.forename: J T
authors.initials: JT
authors.lastname: Abrams
authors.forename: E C
authors.initials: EC
authors.lastname: Vonderheid
authors.forename: S
authors.initials: S
authors.lastname: Kolbe
authors.forename: D M
authors.initials: DM
authors.lastname: Appelt
authors.forename: E J
authors.initials: EJ
authors.lastname: Arking
authors.forename: B J
authors.initials: BJ
authors.lastname: Balin
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology / Q000494:pharmacology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D001706:Biopsy; D002478:Cells, Cultured; D002690:Chlamydia Infections / Q000276:immunology*; D016993:Chlamydophila pneumoniae / Q000235:genetics / Q000276:immunology* / Q000648:ultrastructure; D004817:Epidermis / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D015964:Gene Expression Regulation, Bacterial / Q000276:immunology / Q000528:radiation effects; D006801:Humans; D015603:Keratinocytes / Q000166:cytology; D008070:Lipopolysaccharides / Q000276:immunology / Q000494:pharmacology; D016410:Lymphoma, T-Cell, Cutaneous / Q000188:drug therapy / Q000276:immunology / Q000382:microbiology; D016253:Microscopy, Immunoelectron; D009000:Monocytes / Q000276:immunology / Q000382:microbiology; D011701:PUVA Therapy; D017471:Receptors, Interferon / Q000276:immunology*; D012751:Sezary Syndrome / Q000276:immunology*; D012878:Skin Neoplasms / Q000188:drug therapy / Q000276:immunology / Q000382:microbiology; D013601:T-Lymphocytes / Q000276:immunology*; D014158:Transcription, Genetic / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; C086185:IFNGR2 protein, human; D008070:Lipopolysaccharides; D017471:Receptors, Interferon