Control of established experimental allergic encephalomyelitis by inhibition of tumor necrosis factor (TNF) activity within the central nervous system using monoclonal antibodies and TNF receptor-immunoglobulin fusion proteins

Tumor necrosis factor (TNF) activity was inhibited during the development of actively-induced, chronic relapsing experimental allergic encephalomyelitis (CREAE) in Biozzi AB/H mice, using a mouse TNF-specific (TN3.19.12) antibody and bivalent human p55 and p75 TNF receptor-immunoglobulin (TNFR-Ig) fusion proteins. The development of disease could be inhibited when repeated doses of antibody were administered prior to the anticipated onset. It has now also been shown that a therapeutic effect is evident even when antibody is administered after the onset of clinical signs, further indicating an important role for TNF in pathogenic effector mechanisms in CREAE. Although biologically-active TNF was not detected in the circulation, TNF-α was detected in lesions within the central nervous system (CNS). This suggested that the CNS may be the main site for TNF-specific immunomodulation and was supported by the observation that intracranial injection was significantly more potent than that administered systemically, for both antibody and TNFR-Ig fusion proteins. The fusion proteins were as effective as antibody at doses 10—100-fold lower than that used for antibody, reflecting their higher neutralizing capacity in vitro. Although treatment was not curative and relapse inevitably occurred in this model if treatment was not sustained, the data indicate that anti-TNF immunotherapy, especially within the CNS, can inhibit CREAE and may, therefore, be useful in the control of human neuroimmunological diseases.     

Induction of apoptosis by glyoxal in human embryonic lung epithelial cell line L132

Oxidative stress has been suggested to play a central role in the pathogenesis of lung fibrosis and lung epithelial cell apoptosis is considered to be a key event during fibrogenesis. Studies from various laboratories have indicated that metabolic conditions may initiate oxidative stress, thereby contributing to epithelial cell death. This study was designed to test the hypothesis that glyoxal, an intermediate product in the glycation reaction leading to advanced glycation end products (AGEs), may induce lung epithelial cell apoptosis. We investigated the in vitro effects of glyoxal on fetal human lung epithelial L132 cells. Immunocytochemical analysis of paraffin-embedded cells and fluorescence-activated cell sorter analysis revealed a dose-dependent accumulation of the glycoxidation product (epsilon)N-carboxymethyllysine (CML) in all compartments of the cell. It has been shown that CML modification of proteins may serve as an indicator for oxidative stress. To examine the role of apoptosis in epithelial lung cells we investigated glyoxal-dependent changes in pro- and antiapoptotic mediators bax and activated caspase-3, and galectin-3 and bcl-2, respectively. Increasing concentrations of glyoxal (50 to 400 microM) induced an increase in the number of apoptotic cells. The apoptotic changes were confirmed by transmission electron microscopy. Immunocytochemical analysis of treated cells revealed the presence of other AGEs such as pentosidine as well as products of lipid peroxidation.     

SHIP represses mast cell activation and reveals that IgE alone triggers signaling pathways which enhance normal mast cell survival

The hemopoietic specific, Src homology 2-containing inositol 5' phosphatase (SHIP) hydrolyzes the phosphatidylinositol (PI)-3-kinase generated second messenger, PI-3,4,5-trisphosphate (PIP(3)), to PI-3,4-bisphosphate (PI-3,4-P(2)) in normal bone marrow derived mast cells (BMMCs). As a consequence, SHIP negatively regulates IgE+antigen (Ag)-induced degranulation as well as leukotriene and inflammatory cytokine production. Interestingly, in the absence of SHIP, BMMCs degranulate extensively with IgE alone, i.e. without Ag, suggesting that IgE alone is capable of stimulating signaling in normal BMMCs and that SHIP prevents this signaling from progressing to degranulation. To test this, we compared signaling events triggered by monomeric IgE versus IgE+Ag in normal BMMCs and found that multiple pathways are triggered by monomeric IgE alone and, while they are in general weaker than those stimulated by IgE+Ag, they are more prolonged. Moreover, while SHIP prevents this IgE-induced signalling from progressing to degranulation or leukotriene production it allows sufficient production of autocrine acting cytokines, in part by activation of NFkappaB, to enhance BMMC survival. Interestingly, the activation of NFkappaB and the level of cytokines produced are far higher with IgE than with IgE+Ag. Moreover, IgE alone maintains Bcl-X(L) levels and enhances the adhesion of BMMCs to fibronectin and this likely enhances their survival still further.     

Significance of depression and cognitive impairment in patients undergoing programed stimulation of cardiac arrhythmias

Although depression and cognitive impairment have been associated with excess mortality following heart surgery, the relationship of these factors to death following treatment for cardiac arrhythmias is unknown. We prospectively examined the associations between biobehavioral factors, mortality, and arrhythmia manageability in 88 patients undergoing programed electrical stimulation for the diagnosis and treatment of supraventricular and ventricular tachyarrhythmias or syncope of unknown origin. Statistically significant relationships were identified between depression and mortality, and between cognitive impairment and mortality. No relationships were observed between cognitive impairment or psychologic profile and arrhythmia severity or treatment efficacy. Our data suggest that arrhythmia morbidity and mortality may in part be a function of cognitive and emotional impairments that lessen the individual's capacity to comply with lifesaving therapy, maintain a stable physiologic milieu, and continue an adaptive emotional life. Failure to recognize the clinical significance of these impairments in patients at risk for sudden cardiac death will contribute to the current difficulty reducing the death and disability associated with cardiac arrhythmias.     

The definition of the face.

There is no generally agreed definition of the human and subhuman face. For primatologists the definition forwarded by PERKNOPF (1957) is most agreeable: all structures of the head which can be seen from en face belong to the human face. The face is a combination of structures heterogeneous in both anatomy and function (forehead, eyes, mouth, pelage, etc.). They are different in qualities (e.g., color of the skin or the hair) and quantities as well (length of the jaw or the hairs of the mane). Despite the heterogeneity in form and function, the face as a whole appears as a unit, because in facial expressions there is always more than one structure involved. Blage, etc.). They are different in qualities (e.g., color of the skin or the hair) and quantities as well (length of the jaw or the hairs of the mane). Despite the heterogeneity in form and function, the face as a whole appears as a unit, because in facial expressions there is always more than one structure involved. Blage, etc.). They are different in qualities (e.g., color of the skin or the hair) and quantities as well (length of the jaw or the hairs of the mane). Despite the heterogeneity in form and function, the face as a whole appears as a unit, because in facial expressions there is always more than one structure involved. Because of the frontally oriented eyes and the stereoscopic vision, the facial structures are situated on the head so that they can be seen from in front. This is the reason why primate display mainly face to face. The concepts of the internal and external face are justified only in terms of topographical anatomy.     

The Diversity of Antigen-Specific TCR Repertoires Reflects the Relative Complexity of Epitopes Recognized

Antigen-selected T cell receptor (TCR) repertoires vary in complexity from very limited to extremely diverse. We have previously characterized two different CD8 T cell responses, which are restricted by the same mouse major histocompatibility complex (MHC) class I molecule, H-2 K^d. The TCR repertoire in the response against a determinant from Plasmodium berghei circumsporozoite protein (PbCS; region 252–260) is very diverse, whereas TCRs expressed by clones specific for a determinant in region 170–179 of HLA-CW3 (human) MHC class I molecule show relatively limited structural diversity. We had already demonstrated that cytolytic T lymphocyte (CTL) clones specific for the PbCS peptide display diverse patterns of antigen recognition when tested with a series of single Ala-substituted PbCS peptides or mutant H-2 K^d molecules. We now show that CW3-specific CTL clones display much less diverse patterns of recognition. Our earlier functional studies with synthetic peptide variants suggested that the optimal peptides recognized were 9 (or 8) residues long for PbCS and 10 residues long for CW3. We now present more direct evidence that the natural CW3 ligand is indeed a 10-mer. Our functional data together with molecular modeling suggest that the limited TCR repertoire selected during the CW3 response is not due to a paucity of available epitopes displayed at the surface of the CW3 peptide/K^d complex. We discuss other factors, such as the expression of similar self MHC peptide sequences, that might be involved in trimming this TCR repertoire.     

The glioblastoma-derived T cell suppressor factor/transforming growth factor-beta 2 inhibits T cell growth without affecting the interaction of interleukin 2 with its receptor

Human glioblastoma cells secrete a peptide termed glioblastoma-derived T cell suppressor factor (G-TsF) which inhibits T cell activation. Recently, purification and cloning of G-TsF revealed that G-TsF is identical to transforming growth factor-beta 2. As shown here, G-TsF suppresses the growth of an ovalbumin-specific mouse T helper cell clone (OVA-7T) independently of the stimulus used being either (a) antigen in the presence of antigen-presenting cells, or (b) interleukin 2 (IL2) or (c) phorbol ester and calcium ionophore. Furthermore, in the presence of antibodies against IL2 receptors, G-TsF was able to suppress the residual proliferation still observed when OVA-7T were stimulated with phorbol ester/ionophore. G-TsF failed to inhibit the release of IL3 from OVA-7T activated with IL2. Taken together, the data provide evidence that G-TsF does not directly interfere with interactions of IL2 with its receptor but rather inhibits T cell activation by interfering with an as yet unidentified pathway used by both IL2 and phorbol ester/ionophore. When analyzing different monokines and lymphokines for its effect on G-TsF-induced suppression of T cell growth the only factor found to partially neutralize the effect of G-TsF was tumor necrosis factor-alpha.     

Induction of a cytotoxic T cell response by co-injection of a T helper peptide and a cytotoxic T lymphocyte peptide in incomplete Freund's adjuvant (IFA): Further enhancement by pre-injection of IFA alone

We have previously demonstrated that it is possible to induce a consistent and strong cytolytic T lymphocyte (CTL) response to synthetic peptides, corresponding to poorly immunogenic malaria CTL epitopes, by co-injecting them with peptides representing defined T helper (Th) epitopes in incomplete Freund's adjuvant (IFA). In this study we have tested different immunization protocols to improve further the elicitation of the CTL response. We show that the CTL response to a mixture of Th + CTL peptides administered in IFA was further enhanced by a previous injection of the Th epitope peptide in IFA. Moreover, we found that the response could be significantly augmented by a pre-injection of IFA alone. This enhancement was observed only if the Th epitope was also present in the second injection. The number of lymph node cells recovered was 2–3-fold higher in mice pre-injected with IFA, but the increase in specific CTL activity, expressed as lytic units per animal, by pre-injection of IFA was at least 10–20-fold. Thus, pre-injection of IFA clearly increases the magnitude of a subsequent CTL response.     

Linkage analysis of anorexia and bulimia nervosa cohorts using selected behavioral phenotypes as quantitative traits or covariates.

To increase the likelihood of finding genetic variation conferring liability to eating disorders, we measured over 100 attributes thought to be related to liability to eating disorders on affected individuals from multiplex families and two cohorts: one recruited through a proband with anorexia nervosa (AN; AN cohort); the other recruited through a proband with bulimia nervosa (BN; BN cohort). By a multilayer decision process based on expert evaluation and statistical analysis, six traits were selected for linkage analysis (1): obsessionality (OBS), age at menarche (MENAR), and anxiety (ANX) for quantitative trait locus (QTL) linkage analysis; and lifetime minimum body mass index (BMI), concern over mistakes (CM), and food-related obsessions (OBF) for covariate-based linkage analysis. The BN cohort produced the largest linkage signals: for QTL linkage analysis, four suggestive signals: (for MENAR, at 10p13; for ANX, at 1q31.1, 4q35.2, and 8q13.1); for covariate-based linkage analyses, both significant and suggestive linkages (for BMI, one significant [4q21.1] and three suggestive [3p23, 10p13, 5p15.3]; for CM, two significant [16p13.3, 14q21.1] and three suggestive [4p15.33, 8q11.23, 10p11.21]; and for OBF, one significant [14q21.1] and five suggestive [4p16.1, 10p13.1, 8q11.23, 16p13.3, 18p11.31]). Results from the AN cohort were far less compelling: for QTL linkage analysis, two suggestive signals (for OBS at 6q21 and for ANX at 9p21.3); for covariate-based linkage analysis, five suggestive signals (for BMI at 4q13.1, for CM at 11p11.2 and 17q25.1, and for OBF at 17q25.1 and 15q26.2). Overlap between the two cohorts was minimal for substantial linkage signals.     

Association of BDNF with anorexia, bulimia and age of onset of weight loss in six European populations

Several genes with an essential role in the regulation of eating behavior and body weight are considered candidates involved in the etiology of eating disorders (ED), but no relevant susceptibility genes with a major effect on anorexia nervosa (AN) or bulimia nervosa (BN) have been identified. Brain-derived neurotrophic factor (BDNF) has been implicated in the regulation of food intake and body weight in rodents. We previously reported a strong association of the Met66 allele of the Val66Met BDNF variant with restricting AN (ANR) and low minimum body mass index in Spanish patients. Another single nucleotide polymorphism located in the promoter region of the BDNF gene (-270C>T) showed lack of association with any ED phenotype. In order to replicate these findings in a larger sample, we performed a case-control study in 1142 Caucasian patients with ED consecutively recruited in six different centers from five European countries (France, Germany, Italy, Spain and UK) participating in the 'Factors in Healthy Eating' project. We have found that the Met66 variant is strongly associated to all ED subtypes (AN, ANR, binge-eating/purging AN and BN), and that the -270C BDNF variant has an effect on BN and late age at onset of weight loss. These are the first two variants associated with the pathophysiology of ED in different populations and support a role for BDNF in the susceptibility to aberrant eating behaviors.