Twenty-three subjects were administered three doses of inactivated herpes simplex virus (HSV) type 2 (HSV-2) glycoprotein-subunit vaccine, with doses 2 and 3 being given four and 22 weeks after dose 1. Both HSV-neutralizing antibody and antibody effective in antibody-dependent cell-mediated cytotoxicity were detected in serum samples of 12 of the 13 initially seronegative subjects by week 8. The geometric mean titers of both antibody types decreased between weeks 8 and 22 but increased one week after dose 3. HSV-neutralizing antibody remained detectable in serum samples of seven of the 10 initially seronegative subjects assayed seven months after dose 3. Cell-mediated immunity was detected by lymphocyte transformation responses to HSV-2 after vaccine administration in 12 of the 13 initially seronegative subjects. Unlike humoral antibody, which waned over time, in vitro cell-mediated immune responses remained stable over the seven-month follow-up period after dose 3. This HSV-2-subunit vaccine is well tolerated and elicits both humoral and cell-mediated immune responses to HSV.

Platelet-activating factor (PAF) has been implicated in the development of type 1 diabetes. Our previous studies have suggested that PAF inhibitors reduce insulitis and the frequency of diabetes in BB rats. In this study, serum PAF levels were reduced to address the hypothesis that PAF is important for the development of insulitis. From the age of 35 days on, DP-BB rats were treated with human recombinant PAF acetylhydrolase (rPAF-AH), which efficiently inactivates PAF. Our data indicate that intraperitoneal injections of rPAF-AH reduce the incidence of diabetes in the DP-BB rat. Daily intraperitoneal injections of 6.0 mg/kg body wt rPAF-AH reduced the frequency of diabetes in saline-injected rats from 90% (27/30) to 57% (17/30) (P = 0.004). As found by morphometric analysis on pancreatic islets, DP-BB rats protected from diabetes had less severe degrees of insulitis in a dose-dependent manner. DP-BB rats protected by rPAF-AH also had a higher percentage of insulin-positive cells in pancreas sections compared with those from diabetic animals. We therefore speculated that the beta-cells were protected from insulitis by rPAF-AH.

Objective. To study the distribution of intercellular adhesion molecule receptor (ICAM-R, or ICAM3), a novel ligand for the leukointegrin lymphocyte function-associated antigen 1 (LFA-l), in normal and rheumatoid synovial membranes and to compare this with the distribution of ICAM-1, ICAM-2, vascular cell adhesion molecule 1 (VCAM-l), and endothelial leukocyte adhesion molecule 1 (ELAM-1).Methods. We performed immunohistochemical analyses of frozen sections of normal and rheumatoid synovial tissue using monoclonal antibodies to the molecules examined.Results. ICAM-1 staining was detectable on the vascular endothelium and the synovial lining cells of both normal and rheumatoid synovial membranes. A variable proportion of lymphocytes infiltrating rheumatoid tissues expressed ICAM-1. ICAM-2 staining was demonstrable in the vascular endothelium of both normal and inflamed tissues, the latter demonstrating a significantly higher proportion of positive vessels. ELAM-1 staining was not detectable in normal synovial membranes but was seen on the endothelium of a limited number of rheumatoid synovial vessels, usually close to the synovial lining cell layer. VCAM-1 staining was intense in both normal and rheumatoid synovial lining cells, but vascular staining was weak in both. In conHani El-Gabalawy, MD: The University of Manitoba, Winnipeg, Manitoba, Canada; Michael Gallatin, PhD: ICOS Corporation, Seattle, Washington; Rosemay Vazeux, PhD: ICOS Corporation; Gary Peterman, PhD: ICOS Corporation; John Wilkins, P h D University of Manitoba.Address reprint requests to Hani El-Gabalawy, MD, Rheumatic Disease Unit, 800 Sherbrook Street, Winnipeg, Manitoba R3A 1M4, Canada.Submitted for publication March 31, 1993; accepted in revised form November 30, 1993. trast, ICAM-R staining was not detected in association with any synovial blood vessels, but was widely expressed by lymphocytes and macrophages. Cells of the lining layer did not stain for ICAM-R.Conclusion. Although ICAM-R is a ligand for LFA-1 and shares considerable sequence homology with ICAM-1 and ICAM-2, it does not appear to be expressed by the endothelium of normal or inflamed synovial vessels. Intense expression of ICAM-R by rheumatoid synovial lymphocytes and macrophages suggests that it may play a role in processes requiring cell-cell contact, such as antigen presentation and homotypic aggregation.Chronic inflammatory lesions such as rheumatoid synovitis require ongoing recruitment and retention of leukocytes from the vascular space. A critical initial step involves the adhesion of leukocytes to vascular endothelium (1-3). This is currently thought to be regulated by a cascade of molecular interactions occurring between leukocyte membrane receptors and endothelial counter-receptors, many of which are inducible in their expression. Several endothelial adhesion molecules have been well characterized and shown to participate in leukocyte attachment. These include the endothelial leukocyte adhesion molecule 1 (ELAM-1, or E-selectin) (4), intercellular adhesion molec...

We have derived 33 independent T cell clones from the cerebrospinal fluid (CSF) of a patient with subacute sclerosing panencephalitis using a single T cell cloning method. 6% (2 of 33) of these clones express the T cell receptor gamma (TCR-gamma) protein and are called CSF TCR-gamma clones. Phenotypic analyses of the CSF TCR-gamma clones indicate that they are WT-31-, CD3+, CD4-, and CD8-. The TCR-gamma protein exists on the cell surface as part of an 85-kD disulphide-linked dimer noncovalently associated with the CD3 polypeptides. The CSF TCR-gamma clones have NK-like activity that can be inhibited by anti-CD3 mAbs. Both CSF TCR-gamma clones proliferated in response to anti-CD3 mAbs coupled to Sepharose beads and/or IL-2. Furthermore, stimulation of one of these clones with anti-CD3 mAbs results in a rapid rise in intracellular calcium. These data suggest that T cells bearing the CD3-TCR-gamma protein complex are functional and play a role in the human immune response.

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