We show that extremely fragile biomolecules such as DNA restriction and modifying enzymes can be dried in vitro in the presence of trehalose with no loss of activity, even after prolonged storage. A remarkable and unexpected property of the dried enzyme preparations is their ability to withstand prolonged exposure to temperatures as high as +70 degrees C. This stability is unique to trehalose and is not found with other sugars irrespective of their physical or chemical properties. The immediate significance of these observations is the ability to convert enzymes used in molecular biology into stable reagents. The indefinite stability and high temperature tolerance of these dried enzymes should permit the design of convenient formats that may be of particular significance in the automation of genome mapping and sequencing projects. The stabilization of a wide range of biomolecules by trehalose also has practical implications for a number of areas ranging from basic science, through healthcare and agriculture, to bio-electronics.

Adjuvants were reintroduced into modern immunology as the dirty little secret of immunologists by Janeway and thus began the molecular definition of innate immunity. It is now clear that the binding of pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs) on antigen presenting cells (APCs) activates the innate immune response and provides the host with a rapid mechanism for detecting infection by pathogens and initiates adaptive immunity. Ironically, in addition to advancing the basic science of immunology, Janeway's revelation on induction of the adaptive system has also spurred an era of rational vaccine design that exploits PRRs. Thus, defined PAMPs that bind to known PRRs are being specifically coupled to antigens to improve their immunogenicity. However, while PAMPs efficiently activate the innate immune response, they do not mediate the capture of antigen that is required to elicit the specific responses of the acquired immune system. Heat shock proteins (HSPs) are molecular chaperones that are found complexed to client polypeptides and have been studied as potential cancer vaccines. In addition to binding PRRs and activating the innate immune response, HSPs have been shown to both induce the maturation of APCs and provide chaperoned polypeptides for specific triggering of the acquired immune response.

Human and mouse lymphocytes of T-and B-cell lineages express a protein (Mr, 240,000) that crossreacts with antibodies raised against chicken erythrocyte a-spectrin as judged by immunofluorescence, immunoprecipitation, and immunoautoradiography; by the same criteria, antibodies raised against chicken erythrocyte -spectrin do not react with any lymphocyte polypeptide. In all T and B cells analyzed, before surface-directed ligand challenge with concanavalin A and surface immunoglobulins the polypeptide antigenically related to erythrocyte Of-spectrin is distributed diffusely at the plasma membrane. Upon challenge, the redistribution ofthis polypeptide is concurrent with that ofthe cell-surface receptors initially in patches and then in a cap. Immunoprecipitation of NaDodSO4-solubifized lymphocytes with erythrocyte a-spectrin antiserum shows that in all cases a polypeptide with the same apparent molecular weight as erythrocyte a-spectrin is precipitated. Variable amounts of another polypeptide (Mr, 235,000) are also coimmunoprecipitated. Immunoprecipitations and subsequent immunoautoradiography show that the lymphocyte polypeptide doublet has a composition similar to that of (brain) fodrin, a polypeptide doublet that previously has been found mainly in the cells of nervous tissue.The redistribution ofcell-surface receptors with ligands and immunoglobulins initially involves the aggregation of the receptors into patches, presumably by the diffusion ofthe crosslinked receptors in the plane ofthe membrane, followed by the movement of these patches into a polar cap (1-3). The latter is an energy-dependent nondiffusional process thought to result from a transmembrane association of the receptors with cytoskeletal elements in the cell cortex (4-9). Despite extensive investigations, however, the role ofthe cytoskeleton in the patching and capping of cell-surface receptors in lymphocytes (for a review, see ref. 9) and the problem of how the cytoskeleton interacts with the plasma membrane to a great extent remains unknown. This interaction in the erythrocyte, on the other hand, is well understood and has been shown to be mediated by spectrin, a protein composed of two nonidentical polypeptide subunits (a-spectrin, Mr 240,000; /3-spectrin, Mr 220,000) (for a review, see ref. 10).Recently, it has been shown that nonerythroid cells also express polypeptides that appear to be biochemically and antigenically related to erythrocyte spectrin (ref. 11-18; see also ref. 19). Some cells (e.g., adult cardiac and skeletal muscle cells) express equimolar amounts of polypeptides antigenically related to erythrocyte a-and f3-spectrin (18), whereas other cells (e.g., in nervous tissue) express a polypeptide doublet [termed "fodrin" (13)] composed of a 240,000-dalton component that is antigenically related to erythrocyte a-spectrin and a smaller (235,000) component that does not crossreact with either erythrocyte a-or B-spectrin antiserum (18).In view of the dynamic role of the cytoskeleton during the patching and capping of cell-...

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