Use this URL to cite or link to this record in EThOS:
Title: Characterisation of molecules from cercarial secretions of Schistosoma mansoni and saliva from Ornithodoros moubata
Author: Shawesh, Fawzia
ISNI:       0000 0004 7428 8000
Awarding Body: University of Nottingham
Current Institution: University of Nottingham
Date of Award: 2014
Availability of Full Text:
Access from EThOS:
Molecules in the secretions of S. mansoni cercariae (CTF) aid the penetration of cercariae into host skin. Similarly, molecules in the saliva of 0. moubata (TSG) allow successful feeding. Examples of such molecules are anti-platelet factors, vasodilatory agents and anti-coagulants. These molecules are also exposed to the immune system of the host and induce potent immune responses which may be used for epidemiological analyses of exposure to these parasites. In one-dimensional SDS-PAGE, sera from rabbits immunized with crude homogenates of mouse platelets or human platelets have antibodies (anti-mph and anti-hph respectively) which cross-react strongly with a 46 kDa antigen and weakly with 20 kDa and 70 kDa antigens present in soluble extracts of different life-cycle stages of S. mansoni. Interestingly, the antibodies specific to the 46 kDa S. mansoni protein reacted to a similar-sized molecule in TSG from 0. moubata. Initial mass spectrometric analysis of the 46 kDa band in extracts of S. mansoni and 0. moubata, presumed to be this Platelet-like molecule (PLM46), indicated the molecule was actin. In order to determine whether other proteins of CTF and TSG are present at 46 kDa and to identify the 20 kDa and 70 kDa molecules, two-dimensional gel electrophoresis was performed. The cross-reactive antibodies, affinity purified by acid elution from the electro-blotted 46 kDa protein of both CTF and TSG and antibodies from anti-hph produced by acid elution from nitrocellulose membrane bound CTF and TSG significantly inhibited human and mouse platelet shape change and aggregation induced by agonists such as collagen, thrombin and ADP. When antibodies specific for actin were removed from the anti-hph using purified rabbit actin on .a n affinity column, the inhibitory effect of the cross-reactive antibodies on platelet aggregation still occurred. In order to determine the mechanism of platelet aggregation inhibition by these cross-reactive antibodies, P-selectin expression and fibrinogen binding to platelets were investigated.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available