Anopheles gambiae is the primary vector of human malaria in sub-Saharan Africa. Invasion of Anopheles salivary glands by Plasmodium sporozoites is a necessary step in the transmission of malaria and is likely to be mediated by specific receptor-ligand interactions. We are interested in identifying putative an A. gambiae salivary gland receptor or receptors for sporozoite invasion as a possible target for blocking malaria transmission. By using monoclonal antibodies against female-specific A. gambiae salivary gland proteins, two molecules, one of 29 kDa and one of 100 kDa, were identified and characterized with respect to the age and blood-feeding process of mosquitoes. In an in vivo bioassay, the monoclonal antibody against the 100-kDa protein inhibited Plasmodium yoelii sporozoite invasion of salivary glands >75%. These results show that A. gambiae salivary gland proteins are accessible to monoclonal antibodies that inhibit sporozoite invasion of the salivary glands and suggest alternate targets for blocking the transmission of malaria by this most competent of malaria vectors.

Rabbit forelimb tendons incubated for 15 or 21 days at 35°C in the presence of 8 or 24 mg of glucose/ml were shown to change their chemical, biochemical and mechanical characteristics. The tendons treated with glucose contained up to three times as much hexosyl-lysine and hexosylhydroxylysine as did control tendons as judged by assay of NaB3H4-reduced samples. Measurement of the force generated on thermal contraction showed significant increases in glycosylated tendons compared with controls, indicating the formation of new covalent stabilizing bonds. This conclusion was supported by the decreased solubility of intact tendons and re-formed fibres glycosylated in vitro, and by the evidence from peptide maps of CNBr-digested glucose-incubated tendons. The latter, when compared with peptide maps of control tendons, revealed the presence of additional high-Mr peptide material. These peptides appear to be cross-linked by a new type of covalent bond stable to mild thermal and chemical treatment. This system in vitro provides a readily controlled model -for the study of the chemistry of changes brought about in collagen by nonenzymic glycosylation in diabetes.