Generation of monoclonal antibodies against plant cell-wall polysaccharides. I. Characterization of a monoclonal antibody to a terminal alpha-(1-->2)-linked fucosyl-containing epitope.

Monoclonal antibodies (McAbs) generated against rhamnogalacturonan I (RG-I) purified from suspension-cultured sycamore maple (Acer pseudoplatanus) cells fall into three recognition groups. Four McAbs (group I) recognize an epitope that appears to be immunodominant and is present on RG-I from maize and sycamore maple, pectin and polygalacturonic acid from citrus, gum tragacanth, and membrane glycoproteins from suspension-cultured cells of maize, tobacco, parsley, bean, and sycamore maple. A second set of McAbs (group II) recognizes an epitope present in sycamore maple RG-I but does not bind to any of the other polysaccharides or glycoproteins recognized by group I. Lastly, one McAb, CCRC-M1 (group III), binds to RG-I and more strongly to xyloglucan (XG) from sycamore maple but not to maize RG-I, citrus polygalacturonic acid, or to the plant membrane glycoproteins recognized by group I. The epitope to which CCRC-M1 binds has been examined in detail. Ligand competition assays using a series of oligosaccharides derived from or related to sycamore maple XG demonstrated that a terminal alpha-(1-->2)-linked fucosyl residue constitutes an essential part of the epitope recognized by CCRC-M1. Oligosaccharides containing this structural motif compete with intact sycamore maple XG for binding to the antibody, whereas structurally related oligosaccharides, which do not contain terminal fucosyl residues or in which the terminal fucosyl residue is linked alpha-(1-->3) to the adjacent glycosyl residue, do not compete for the antibody binding site. The ligand binding assays also indicate that CCRC-M1 binds to a conformationally dependent structure of the polysaccharide. Other results of this study establish that some of the carbohydrate epitopes of the plant extracellular matrix are shared among different macromolecules.

Consultation and supervision in cases of non-accidental injury to children.

Consultation and supervision play an essential role in the management of the anxieties, conflicts and demands experienced by those working long-term with cases of non-accidental injury. In our setting we employ our own external staff consultant and in turn our workers offer a consultative service to workers from other agencies. It seems to us that consultation and supervision are inter-related but distinct processes: consultation is essentially experiential and non-directive; supervision is didactic and directive. A consultant may give advice from his own area of expertise (which may be different from that of the consultor), but he may also be called upon to interpret or comment on other areas, such as the conflicts between workers and their clients or workers and their organizations. A consultant may also be called on to offer a model of supervision to supervisor and worker. A supervisor, by definition, is expert in the area of work of the worker and in a position within the organization to give direction. He at times, however, will be called upon for non-directive discussion and comment--in effect consultation. He may also have to fill the role of manager and resource provider. Our experience shows it is essential to clarify this inter-relationship as a first step to exploring the skills necessary for supervisor and consultant to help workers fulfil their task.

An international look at school-based children's dental services.

School-based dental clinics, when well-managed, can bring good quality care to children where they normally congregate, thus avoiding many of the problems found where children must be taken to private offices out of school hours. Both capital and running expenses for primary care can be substantially reduced. Utilization figures for school-based dental services now reach 98 per cent of eligible children in New Zealand, where dental nurses do simple operative dentistry including cavity preparation and fillings. Australia, where a modified New Zealand plan has been expanding for about 12 years, is moving rapidly to attain similar utilization. In Sweden, 95 per cent of the school-age population is reported to receive school-managed dental service through a government program. In the United States, however, it is commonly reported that less than one-half the school-age population receives good periodic dental care.