Promotion of central nervous system remyelination by induced differentiation of oligodendrocyte precursor cells.

Objective: Repair of demyelinated axons in diseases such as multiple sclerosis requires activation of the myelination program in existing or newly recruited oligodendrocyte precursor cells (OPCs). The control of OPC differentiation and initiation of myelination during repair is poorly understood. In this study, we test the ability of anti-LINGO-1 reagents to promote myelination in vitro and remyelination in the rodent adult central nervous system in vivo.

Epitope-dependent effect of anti-murine TIM-1 monoclonal antibodies on T cell activity and lung immune responses.

The TAPR locus containing the TIM gene family is implicated in the development of atopic inflammation in mouse, and TIM-1 allelic variation has been associated with the incidence of atopy in human patient populations. In this study, we show that manipulation of the TIM-1 pathway influences airway inflammation and pathology. Anti-TIM-1 mAbs recognizing distinct epitopes differentially modulated OVA-induced lung inflammation in the mouse.

T cell, Ig domain, mucin domain-2 gene-deficient mice reveal a novel mechanism for the regulation of Th2 immune responses and airway inflammation.

The development of asthma and other atopic diseases is influenced by cytokines produced by Th2 effector T cells. How effector T cell responses are regulated once these cell populations are established remains unclear. The recently described T cell and airway phenotype regulator locus, containing the T cell, Ig domain, mucin domain (TIM) genes, is genetically associated with Th2 cytokine production and Th2-dependent immune responses.

Cutting edge: BAFF regulates CD21/35 and CD23 expression independent of its B cell survival function.

Herein we demonstrate that B cell-activating factor of the TNF family (BAFF), a B cell survival factor, also regulates CD21/35 and CD23 expression. BAFF blockade in wild-type mice down-modulates CD21/35 and CD23 on B cells while survival remains intact, and BAFF exposure causes elevated CD21/35 and CD23 expression. Similar down-modulation is observed in bcl-2-transgenic mice treated with a BAFF inhibitor.

MyoD-positive myoblasts are present in mature fetal organs lacking skeletal muscle.

The epiblast of the chick embryo gives rise to the ectoderm, mesoderm, and endoderm during gastrulation. Previous studies revealed that MyoD-positive cells were present throughout the epiblast, suggesting that skeletal muscle precursors would become incorporated into all three germ layers. The focus of the present study was to examine a variety of organs from the chicken fetus for the presence of myogenic cells.

Betaine-homocysteine methyltransferase expression in porcine and human tissues and chromosomal localization of the human gene.

We have prepared antibodies against porcine liver betaine-homocysteine methyltransferase (BHMT; EC 2.1.1.

Antibody networks and imaging: elicitation of anti-fluorescein antibodies in response to the metatypic state of fluorescein-specific monoclonal antibodies.

Studies are described regarding generation of anti-hapten antibodies starting with a monoclonal Ig immunogen in the ligand-induced conformation or metatypic state. Liganded monoclonal Ab1 antibodies represent the unique feature of the study since previous reports investigating internal imaging in the original Idiotype Network Hypothesis [Jerne, 1974 (Ann. Immun.

Determination of hydrolysed fumonisin B1 (HFB1) in corn by competitive direct enzyme-linked immunosorbent assay.

Fumonisin B1, a mycotoxin produced by certain Fusarium moulds, consists of two tricarballyic acid groups esterified to a 20-carbon backbone. Under alkaline conditions, or through metabolism, the aminopentol backbone, also known as hydrolysed Fumonisin B1 (HFB1) can be formed and is itself cytotoxic. Although the occurrence of HFB1 in corn-based foods is suspected, because of the ubiquitous nature of FB1 in corn, analytical methods for its detection are difficult.

High-affinity rat anti-fluorescein monoclonal antibody with unique fine specificity properties including differential recognition of dynamic ligand analogues.

The ability of antibodies to specifically select and stabilize through binding one or more isomers of highly dynamic ligands remains a relatively unexplored immunochemical problem. The experimental strategy employed in this study was to elicit homogeneous antibodies to polyaromatic fluorescein which exists in one isomeric form. The binding properties of a monoclonal rat antifluorescein antibody specific to a given isomer were quantitatively studied to determine the capacity to bind dynamic analogues of fluorescein which exists in multiple isomers.

Elicitation of distinct populations of monoclonal antibodies specific for the variable domains of monoclonal anti-fluorescein antibody 4-4-20.

Armenian hamsters were immunized with non-liganded, partially liganded or affinity-labeled anti-fluorescein Mab 4-4-20. Seventeen hybridoma producing monoclonal anti-4-4-20 antibodies were characterized from chemically-mediated fusions of immune hamster lymphocytes with murine Sp2/O-Ag14 myeloma cells. Distinct populations of anti-4-4-20 monoclonal antibodies were isolated from hamsters receiving immunizations with partially liganded Mab 4-4-20 relative to those receiving affinity-labeled 4-4-20.

Monoclonal antibodies against a dopamine-releasing protein (DARP) arrest fetal development, decrease brain catecholamines, and increase adrenal weight of neonatal rats.

Monoclonal antibodies (MAb) were produced against a partially purified dopamine-releasing protein (DARP) to examine the feasible physiological role of this factor during the development of the rat. These IgM isotype MAbs, and not other IgM antibodies (controls), induced a remarkable increase in fetal resorption and stillbirth rate and impaired the developmental increase of catecholamine concentration in the corpus striatum and hypothalamus of newborn rats. Neonatal injections of the anti-DARP MAb (a single injection of 200 mug, 24 h after birth or 40 mug on alternate days during the first 10 days) decreased the dopamine (DA) concentration of the corpus striatum by 30% on Day 10 and 15% on Day 25 and drastically impaired (by 43% on Day 25) the developmental increase in hypothalamic DA.

Hemocytes contribute to both the formation and breakdown of the basal lamina in developing wings of Manduca sexta.

Monoclonal antibodies (MAbs) raised against wing tissues of Manduca sexta recognize epitopes shared by both hemocytes and basal laminae. During the last larval stadium, the basal lamina of moth wing epithelium forms after hemocytes have migrated into the space adjacent to basal surfaces of epithelial cells. As adult development commences, hemocytes participate in phagocytosis of the same basal lamina; and as dissolution of the basal lamina proceeds (day 2-day 5 post-pupation), wing epithelial cells send forth long basal processes and rearrange within the plane of the epithelium.

Polyclonal antibodies specific for liganded active site (metatype) of a high affinity anti-hapten monoclonal antibody.

Syngeneic polyclonal antibodies were elicited to an affinity labeled high affinity (2-3 X 10(10) M-1) anti-fluorescein murine IgG2a monoclonal antibody. Hyperimmune ascites fluid was tested for reactivity with homologous liganded, affinity labeled and non-liganded Fab fragments derived from the high affinity antibody. Binding results demonstrated antibody specificity for the liganded or affinity labeled site, but no reactivity with either the non-liganded form or the fluorescyl ligand.

Functional and structural implications of variable region immunoglobulin dynamic states.

The consequence of multiple conformational states in the immunoglobulin variable region are considered. Bound ligand is viewed as a stabilizer of one conformer from a series of non-liganded conformers. Kinetic, equilibrium, thermodynamic and crystal formation information are used as supporting evidence for a unique conformer which is the crystallizable liganded state.