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Cell wall polysaccharides are some of the most complex biopolymers known, and yet their functions remain largely mysterious. Advances in imaging methods permit direct visualisation of the molecular architecture of cell walls and the modifications that occur to polymers during growth and development. To address the structural and functional relationships of individual cell wall components, we need to better characterise a broad range of structural and architectural alterations in cell walls, appearing as a consequence of developmental regulation, environmental adaptation or genetic modification. We have developed a rapid method to screen large numbers of plants for a broad range of cell wall phenotypes using Fourier transform infrared microspectroscopy and Principal Component Analysis. We are using model systems to uncover the genes that encode some of the cell-wall-related biosynthetic and hydrolytic enzymes, and structural proteins.

Allogeneic rat mixed-thymocyte 48 h culture-conditioned medium (MTM) was used successfully in place of feeder cells for hybridoma production with the NS-1 and NS-0 plasmacytoma lines. It permitted lower concentrations of fused cells to be seeded, and supported the transition from 96 to 24 well plates. MTM improved the performance of poor sera during cloning. It also assisted the survival of cells that were sensitive to thawing from liquid nitrogen storage, and cells that had inadvertently been allowed to overgrow. Two rats could produce the equivalent of 1500-5000 ml feeder cell suspension according to the dilution used; 150-500 mice would be required to produce such a quantity of cells. Thus use of MTM entailed a considerable saving in mice and provided a secure supply of 'reagent', since a batch could be prepared, checked for sterility, frozen and stored indefinitely.

Rhesus haemolytic disease of the newborn is a condition which can result in intrauterine or perinatal death. Although the passive administration of therapeutic anti-D post-partum is a most effective method for the prevention of this condition, there is currently a shortage of immune plasma for the preparation of the therapeutic anti-D immunoglobulin product. In addition the availability of anti-D for use in blood grouping has also been reduced. The advances made in recent years in the techniques for the production of human monoclonal antibodies raise the possibility that human monoclonal anti-D-based products may provide solutions to both of these problems. There are now a number of reports of the production of stable cell lines secreting high titre human anti-D. In this review we consider the various strategies used in the production of human monoclonal anti-D-secreting cell lines, the basic properties of these reagents and their potential usefulness in blood grouping, in therapy and as research tools.