Copper complexes of a range of ligands have been prepared and evaluated for antiinflammatory activity and irritancy after oral, subcutaneous, and local administration in rats and guinea pigs. The antiinflammatory activities were found to depend on the species used and the route of administration. When nonantiinflammatory ligands were used, the response was generally dose dependent. With D-penicillamine and when the ligands were themselves antiinflammatory in animal models of inflammation--as was the case with flufenamic acid, levamisole, aspirin, L-histidine, and 2-amino-2-thiazoline--differences in antiinflammatory activity were observed between the copper complexes and the free ligands. In some cases, the copper complexes were the more effective. There was a weak correlation between local (subplantar) irritation and the dose of copper but, for four compounds studied in more detail, the response in the local subplantar test and degree of antiinflammatory activity were not related, suggesting that the action of copper is not solely by a counterirritant mechanism. No obvious differences between the activities of copper(I) and copper(II) compounds were observed, suggesting that a common metabolite may be involved in the antiinflammatory action of copper.

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Theileria annulata is an economically important protozoan parasite that threatens an estimated 250 million cattle with the disease tropical theileriosis. Development of a defmed subunit vaccine is one means of trying to develop control measures against the disease. To this end we have characterized a surface antigen complex of the infective stage (sporozoite), by using a monoclonal antibody that neutralizes sporozoite infectivity in vitro. We have cloned the gene coding for this complex and have demonstrated that a fusion protein expressed from a fragment of this gene elicits strong neutralizing antibodies. Furthermore we provide data on the structure and expression of this gene. In particular we show that the region of the gene, expressed in one clone, codes for a protein segment relatively rich in proline residues. Also we demonstrate that expression of this gene appears to be stage specific, transcripts being present only in the sporoblast and sporozoite stages. The relevance of these rmdings to the production of a defined subunit vaccine is discussed.Tropical theileriosis threatens an estimated 250 million cattle in the Mediterranean littoral, North Africa, the Middle East, the Indian subcontinent, and Central Asia and acts as a major constraint on livestock production and improvement in many developing countries (1). The disease is caused by a tickborne protozoan, Theileria annulata, which enters the bovine host as the infective sporozoite stage in the saliva of a feeding tick. These sporozoites rapidly invade mononuclear cells in which the macroschizont stage develops; subsequently these parasites are liberated, whereupon they invade erythrocytes producing the piroplasm stage of the life cycle (2). Present methods of vaccination depend upon establishing active infection (3) and thus incur both the risk of causing clinical disease and the problems of handling live parasite material under tropical conditions. For these reasons we are actively engaged in identifying parasite antigens capable of inducing a protective immune response (4-6) using similar approaches to those followed by investigators working on Theileria parva, the cause of East Coast fever (7-11). Here we describe an antisporozoite monoclonal antibody (mAb) that exhibits significant sporozoite neutralizing activity and provide data on the nature of the polypeptides recognized by this antibody. In addition we describe the isolation of two recombinant DNA clones that express the epitope defined by this mAb and we report our findings on the structure and expression of this gene(s). § MATERIALS AND METHODSParasite Material. Three uncloned isolates of Theileria annulata were used in this study: they are called Ankara, from Turkey (12); Hissar, from India (13); and Gharb, from Morocco (14). Sporozoites for mAb production, immunofluorescence tests, inhibition assays, and immunoblotting were obtained from Theileria annulata-infected adult ticks (Hyalomma anatolicum anatolicum). These ticks were fed on rabbits for 3 days to stimulate sporozoite m...

A.G base-paired mismatches that occur during replication are among the most difficult to detect by repair enzymes. Such purine.purine mispairs can exist in two conformations, one of which is stabilized by protons [Gao & Patel (1988) J. Am. Chem. Soc. 110, 5178-5182]. We have undertaken a 1H-n.m.r. and 31P-n.m.r. study of the mismatched dodecamer d(CGCAAATTGGCG)2 as a function of both temperature and pH to determine the conformational features of the A.G mismatch. At pH greater than 7 the mispaired bases are each in the anti conformation and are stacked in the B-like helix. As the pH is decreased, a second conformation becomes populated (apparent pKa approx. 5.9) with concomitant changes in the chemical shifts of protons of the mispaired bases and their nearest neighbours. Data from two-dimensional nuclear-Overhauser-enhancement spectroscopy show unequivocally that, at low pH, the dominant conformation is one in which the mismatched G residues are in the syn conformation and are hydrogen-bonded to the A residues that remain in the anti conformation. Residues not adjacent to the A.G sites are almost unaffected by the transition or the mispairing, suggesting considerable local flexibility of the unconstrained duplexes. Despite the bulging of the mispaired bases, the conformation of the A(anti).G(anti) duplex is very similar to the native dodecamer, whereas the AH+(anti).G(syn) duplex shows a greater variation in the backbone conformation at the mismatched site. According to the chemical shifts, the duplex retains twofold symmetry in solution. The equilibrium between the syn and anti conformations of G9/G21 is strongly dependent on pH, but only weakly dependent on temperature (delta H approx. 16 kJ.mol-1). The first-order rate constant for the transition is approx. 9 s-1 at 283 K and approx. 60 s-1 at 298 K, with an activation enthalpy of approx. 100 kJ.mol-1. The stabilization of the A(anti).G(syn) conformation by protons is consistent with models invoking N1 protonation of adenine. Using the derived glycosidic torsion angles we have used restrained molecular dynamics to build models of the neutral and protonated d(CGCAAATTGGCG)2 oligomers. The results confirm that the A(anti).G(anti) and AH+(anti).G(syn) conformations are favoured at high pH and low pH respectively, in accord with n.m.r. and single-crystal X-ray data.