Because monoclonal antibodies (mAbs) directed against ␣ 4-integrin and VCAM-1 inhibit the development of experimental autoimmune encephalomyelitis (EAE) in vivo, it has been concluded that the successful therapeutic effect is due to interference with ␣ 4 ␤ 1/VCAM-1-mediated interaction of autoaggressive T cells with the blood-brain barrier. A possible role for ␣ 4 ␤ 7-integrin, or interference with other T cell mediated events during the pathogenesis of EAE, has not been considered. We have compared the effects of mAb therapy on the development of EAE in the SJL/N mouse, using a large panel of mAbs directed against ␣ 4, ␤ 7, the ␣ 4 ␤ 7-heterodimer, and against VCAM-1. Although encephalitogenic T cells express both ␣ 4-integrins, mAbs directed against the ␣ 4 ␤ 7-heterodimer or against the ␤ 7-subunit did not interfere with the development of EAE. In contrast, mAbs directed against ␣ 4 and VCAM-1 inhibited or diminished clinical or histopathological signs of EAE. Our data demonstrate for the first time that ␣ 4 ␤ 7 is not essential for the development of EAE.

The functional expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and MAdCAM-1 in the choroid plexus is indicative of a role of this structure in the communication of the immune system with the central nervous system (CNS). In order to gain further insight into the possible functions of adhesion molecules expressed in the choroid plexus, we investigated the exact ultrastructural localization of VCAM-1, ICAM-1 and MAdCAM-1 on semithin and ultrathin cryosections of the choroid plexus of healthy mice and of mice suffering from experimental autoimmune encephalomyelitis (EAE). In the healthy choroid plexus VCAM-1 and ICAM-1, but not MAdCAM-1, could be detected on the apical surface of the choroid plexus epithelial cells. During EAE, immunoreactivity for VCAM-1 and ICAM-1 was dramatically increased. Additionally, apical expression of MAdCAM-1 was observed on individual choroid plexus epithelial cells during EAE. At the same time, VCAM-1, ICAM-1 or MAdCAM-1 were never present on the endothelial cells of the fenestrated capillaries within the choroid plexus. The polar expression of VCAM-1, ICAM-1 and MAdCAM-1 on the apical surface of choroid plexus epithelial cells, which form the blood-cerebrospinal fluid barrier, implies a previously unappreciated function of this barrier in the immunosurveillance of the CNS.

A novel monoclonal antibody (mAb), 8D3 (IgG2a), that specifically recognizes the murine transferrin receptor (TfR) was produced by immunizing a Lewis rat with a polyoma middle T oncogene-transformed endothelioma cell line. The 8D3 mAb was obtained by immunohistochemical screening for exclusive staining of vessels forming a blood-brain barrier (BBB), but not of other vessels. The anti-TfR mAb 8D3 recognizes the TfR also in FACS analysis and in western blots and should prove to be useful for affinity purification of the TfR. Whereas 8D3 brightly stains BBB-forming vessels in the central nervous system of mice, it does not stain the fenestrated capillaries within the choroid plexus and the circumventricular organs. In testis, where the blood-tissue barrier is located at the level of the Sertoli cells, the 8D3 mAb specifically stains Sertoli cells but not endothelial cells. Finally, in vitro, 8D3 does not interfere with iron uptake of lymphocytes as it does not influence their proliferation. Taken together, 8D3 represents a versatile new tool to study the tissue distribution of the murine TfR and TfR-mediated transcytosis across tissue barriers in the mouse.

No abstract

No abstract

CCKB receptors are expressed in the rat kidney on tubules and collecting ducts. These receptors mediate changes in renal potassium and sodium absorption. In addition, gastrin causes a decrease in perfusate flow, indicating that CCKB receptors might also modulate vascular resistance in the kidney.

In experimental autoimmune encephalomyelitis (EAE) inflammatory cells cross the endothelial blood-brain barrier (BBB) and gain access to the central nervous system (CNS). Here we show that E- and P-selectin are not involved in the recruitment of inflammatory cells across the BBB. Neither expression of E- nor P-selectin is induced in BBB-forming endothelium at any time after initiation of EAE. Some of the inflammatory cells present in the CNS during EAE express ligands for E- or P-selectin. However, anti–E- and P-selectin antibodies influence neither immigration of inflammatory cells across the BBB nor the development of EAE. In general, suppression of E- and P-selectin expression on BBB endothelium is dependent on factors derived from the CNS microenvironment, eg, astrocytes. Our results suggest that during EAE suppression of E- and P-selectin expression on the BBB provides a CNS-specific mechanism to reduce leukocyte recruitment into the CNS.

The Mouse Grimace Scale (MGS) has been widely used for the noninvasive examination of distress/pain in mice. The aim of this study was to further improve its performance to generate repeatable, faster, blinded and reliable results for developing automated and standardized pictures for MGS scoring and simultaneous evaluation of up to four animals. Videos of seven C57BL/6N mice were generated in an experiment to assess pain and stress induced by repeated intraperitoneal injection of carbon tetrachloride (CCl4). MGS scores were taken 1 h before and after the injection. Videotaping was performed for 10 min in special observation boxes. For manual selection, pictures of each mouse were randomly chosen for quality analysis and scored according six quality selection criteria (0 = no, 1 = moderate, 2 = full accordance); the maximum possible score was 12. Overall, 609 pictures from six videos were evaluated for MGS scoring quality; evaluation was performed by using the picture selection tool or by manual scoring. With manual scoring, 288 pictures (48.3% of all randomly generated pictures) were deemed scorable using MGS (mean score = 22.15 ± SD 6.3). To evaluate the algorithm, ratings from different rater groups (beginner, medium-level trained, professional) were compared with the automated image generated. These differences were not significant ( p = 0.1091). This study demonstrates an improved set-up and a picture selection tool that can generate repeatable, not-observer biased and standardized pictures for MGS scoring.