Properties of antibodies to a synthetic peptide representing an epitope shared by receptors of the type I cytokine family.

Previous works from our laboratory demonstrated that the monoclonal antibody (MAb) called R7B4 is directed to an epitope shared by various receptors corresponding to the type I cytokine receptor family, containing the common motif WSXWS or the homologous F(Y)GEFS. Later a consensus peptide significantly recognized by the MAb was identified and synthesized (sequence HGYWSEWSPE). In the present work, an homologous of the consensus sequence (HHGYWSEWSPE) was conjugated to PADRE adjuvant to produce Ab that could simulate theMAb activity, that is, acting as hormone and/or cytokine antagonists. The covalently conjugated peptide-PADRE was a better immunogen than the consensus peptide alone according to the reactivity of sera from C57BL/6 immunized mice and, besides, no Ab to PADRE were detected. Furthermore, Ab to consensus peptide elicited after peptide-PADRE inoculation into mice behaved as immunomodulatory agents, since they improved the humoral response to a foreign antigen (in this case ovalbumin). In addition, the Ab inhibited the in vitro proliferation of various cell lines, mainly cells derived from human and mouse breast cancer. Thus, immunization with the conjugate peptide-PADRE prepared under the experimental conditions described herein originated immunomodulatory Ab that, in the future, could be tested in some pathological conditions.

Morphometric study on cytoskeletal components of neuronal and astroglial cells after chronic CB1 agonist treatment.

One of the major goals for the use of digital image analysis systems in neuroanatomy is to visualize structures, cells, or other tissue components in order to compare various populations. In addition, digital image analysis allows semi-quantification of cell labeling because it is capable of measuring simultaneously the staining intensity, location, size, and shape of labeled profiles. In the present work, the morphological changes in the CB1 hippocampal area and corpus striatum induced by chronic treatment with the synthetic CB1-receptor agonist WIN55,212-2 were analyzed as an example of digital image analysis application. Twice-daily treatment for 14 d with the CB1-receptor agonist demonstrated significant changes in the expression of neuronal cytoskeletal proteins and in neuronal morphology, as evidenced by immunocytochemical and digital analysis studies. However, changes in the expression of astroglial cytoskeletal proteins were not found.

Altered neuron-glia interactions in a low, chronic prenatal ethanol exposure.

Serotoninergic neurons, astrocytes and nitrergic system play an important role in central nervous system (CNS) development. These systems are altered in prenatal ethanol exposure (PEE) but ethanol (EtOH) effects may be very diverse under different conditions. In this study, we analyzed morphologically two serotoninergic mesencephalic nuclei and three prosencephalic areas of serotoninergic innervation in a model of pre- and postnatal low-ethanol exposure. Female Wistar rats were orally exposed to EtOH 6.6% (v/v), ad libitum, for 6 weeks before mating and during gestation and lactation while control group received water ad libitum. Twenty-day-old offspring (P21) brains were processed and immunoreactivity (IR) using antibodies against tryptophan hydroxylase (TPH), 5-HT, 5-HT transporter (5HTT), glial fibrillary acidic protein (GFAP), S-100B protein, 200-kDa neurofilaments (Nf-200) and neuronal nitric oxide synthase (nNOS) was evaluated. Dorsal and median raphe nucleus (DRN and MRN), hippocampus (Hipp), striatum (Strt) and frontal cortex (FCx) were studied by computer-assisted image analysis. Relative optical density (ROD) of TPH-IR, 5-HT-IR and nNOS-IR neurons; cell area of GFAP-IR astrocytes; relative area of 5HTT-IR fibers and Nf-200-IR were evaluated. TPH-IR was increased in DRN and MRN and 5-HT-IR was increased only in MRN. 5-HTT-IR fibers and ROD of S-100B-IR astrocytes were increased in the three prosencephalic areas while GFAP-IR astrocytes were hypertrophied only in Hipp and FCx. Nf-200 expression was increased in Hipp and Strt and morphologically altered in the FCx. ROD of nNOS-IR neurons was increased in Strt and FCx but was not detected in Hipp. We have also detected morphological changes resembling accelerated development and maturation, and early aging. Considering the evidences of a close 5-HT-astroglial-NO relationship during CNS development the differential response of the studied regions is an interesting result that could be due to different gradients of development in the studied areas and/or different responses of those areas to the effects of a low pre- and postnatal ethanol exposure.