Thesis (Ph. D.)--University of Manitoba, 1995. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Manitoba, 1997. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Rochester, 1999. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Manitoba, 1997. / Includes bibliographical references.

Thesis (doctoral)--Rijksuniversiteit te Utrecht.

Thesis--University of Turku, Finland, 1999. / Includes bibliographical references.

Thesis--University of Turku, Finland, 1999. / Includes bibliographical references.

Thesis (doctoral)--Rijksuniversiteit te Utrecht.

Streptococcus mutans is the main causative agent of dental caries, which is a widespread infectious disease. A number of surface molecules are involved in the pathogenicity of this organism, including adherence and aggregation factors. The wall-associated protein A (WapA) of Streptococcus mutans GS-5 was previously demonstrated to be a sucrose-dependent adherence and aggregation factor, and is a larger precursor to extracellular antigen A (AgA), a candidate antigen for a dental caries vaccine.The full-length wapA gene and a C-terminal truncated version agA encoding the AgA were cloned into the mammalian expression vector pcDNA 3.1/V5/His-TOPO. The above constructs were mixed with a cationic lipid and used to transfect Chinese hamster ovary (CHO) cells. Transient expression of the wapA and agA genes was observed at 24 h post-transfection, as shown by Western immunoblot analysis. In CHO, cells WapA containing the membrane and wall-spanning region was found in apoptotic bodies, whereas the soluble AgA, which lacked the hydrophobic region, was found in extracellular medium. A higher salivary IgA level was observed in mice immunized with the pcDNA-wapA vaccine as compared to those immunized with the pcDNA-agA vaccine. Furthermore, the anti-WapA antibody inhibited S. mutans sucrose-dependent adherence, suggesting potential protection of the tooth against S. mutans colonization, while anti-AgA had no significant effect. Indeed, prediction and analysis of protein epitopes showed that WapA contains highly promiscuous MHC-II binding motifs that are absent from AgA. Immunodot assay confirmed that WapA bound biotin-labeled dextran, whereas AgA did not.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.