3
Views
4
CrossRef citations to date
0
Altmetric
Original Article

Purified Vi Antigens as Possible Typhoid Vaccines

&
Pages 227-238 | Published online: 07 Jul 2009
 

Abstract

Two purified samples and one crude preparation of Vi antigen were studied to determine their potential as typhoid vaccines. Each preparation was characterized by mouse toxicity studies, pyrogen tests in rabbits, and active protection tests in mice. Both purified samples of Vi antigen were nontoxic and nonpyrogenic in the highest doses tested (500 üg). In contrast the LD50 for the crude Vi antigen preparation was approximately 500üg, while the minimum pyrogenic dose was approximately 0.1 üq. In protection studies each Vi antigen preparation was compared with commercially obtained, heat-killed, phenol-preserved (HP) typhoid vaccine. With doses of 1 üg or 10 üg for the appropriate Vi antigen, mice were protected to an extent comparable to, or, in most instances, significantly greater than were mice receiving a standard dose (0.5 ml) of the HP vaccine. Since it elicits no toxic or febrile response in doses which evoke a high degree of protection in the standard bioassay in mice, purified Vi antigen represents a favorable alternative to the currently employed HP vaccine.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.