Sézary T-cell activating factor is a Chlamydia pneumoniae-associated protein.

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.

Frequency of apolipoprotein E (APOE) allele types in patients with Chlamydia-associated arthritis and other arthritides.

Genetic background is important in determining whether certain infecting bacteria disseminate to the joint and cause arthritis. We assessed whether APOE genotype is associated with the presence of DNA from Chlamydia or other bacteria in synovial tissues of patients with various arthritides. Nucleic acids from synovial tissues of 135 patients were screened by PCR for DNA from Chlamydia trachomatis, C. pneumoniae and other bacteria (pan-bacteria). APOE genotype was determined by a PCR-based method for all patients in each of four resulting groups comprised of about 35 individuals each, positive for C. trachomatis only, C. pneumoniae only, other bacteria, or no bacteria. RT-PCR was used to assess synovial APOE expression. The latter assays confirmed that APOE mRNA is present in synovial tissue. Determination of APOE genotype showed that patients PCR-negative in all assays, and those positive in the C. trachomatis - and pan-bacteria- (excluding Chlamydia) directed assays, had distributions of the APOE epsilon2, epsilon3 and epsilon4 alleles mirroring those of the general population (i.e. about 8%, 79% and 13%, respectively). In contrast, 68% of patients with C. pneumoniae DNA in synovium possessed a copy of the epsilon4 allele. These results indicate that no association exists between APOE genotype and synovial presence of C. trachomatis or other bacteria. However, individuals bearing at least one copy of the APOE epsilon4 allele may be at increased risk for synovial infection by C. pneumoniae.

Angioarchitecture of the CNS, pituitary gland, and intracerebral grafts revealed with peroxidase cytochemistry.

Blood vessels of the fetal, neonatal, and adult subprimate and primate CNS, including circumventricular organs (e.g., median eminence, pituitary gland, etc.), and of solid CNS and nonneural (anterior pituitary gland) allografts placed within brains of adult mammalian hosts were visualized with peroxidase cytochemistry applied in three ways: to tissues from animals injected systemically with native horseradish peroxidase (HRP) or peroxidase conjugated to the lectin wheat germ agglutinin (WGA) prior to perfusion fixation; to tissues from animals infused with native HRP into the aorta subsequent to perfusion fixation; and to tissues from animals fixed by immersion and incubated for endogenous peroxidase activity in red cells retained within blood vessels. In neonatal and adult animals receiving native HRP intravascularly, non-fenestrated vessels contributing to a blood-brain barrier were outlined with HRP reaction product when tetramethylbenzidine (TMB) as opposed to diaminobenzidine (DAB) was used as the chromogen; fenestrated vessels of circumventricular organs were not discernible due to the density of extravascular reaction product. Fenestrated and non-fenestrated cerebral and extracerebral blood vessels exposed to bloodborne WGA-HRP were visible when incubated in TMB and DAB solutions. Native HRP infused into the aorta of fixed animals likewise labeled non- fenestrated vessels throughout the brain upon exposure to TMB or DAB but obscured fenestrated vessels of the circumventricular organs. Endogenous peroxidase activity of red cells, seen equally well with TMB and DAB, outlined blood vessels throughout the cerebral gray and white matter and all circumventricular organs in fetal, neonatal, and adult animals. Application of the three peroxidase cytochemical approaches to study the development or absence of a blood-brain barrier in intracerebral allografts demonstrated that the vascularization of day 16-19 fetal/1 day neonatal CNS allografts is not well defined prior to 7 days following intracerebral placement of the grafts. CNS allografts secured from donor sites expected to possess a blood-brain barrier exhibited blood vessels that were not leaky to HRP injected intravenously in the host. Fenestrated blood vessels associated with anterior pituitary allografts were evident prior to 3 days posttransplantation within the host brain and permitted blood-borne HRP in the host to enter the graft and surrounding host brain parenchyma.