phoP/phoQ-deleted Salmonella typhi (Ty800) is a safe and immunogenic single-dose typhoid fever vaccine in volunteers.

Publisher: Oxford University Press Country of Publication: United States NLM ID: 0413675 Publication Model: Print Cited Medium: Print ISSN: 0022-1899 (Print) Linking ISSN: 00221899 NLM ISO Abbreviation: J Infect Dis Subsets: MEDLINE

Publication: Jan. 2011- : Oxford : Oxford University Press
Original Publication: 1904-2010 : Chicago, IL : University of Chicago Press

Antibodies, Bacterial/*blood ; Salmonella typhi/*immunology ; Typhoid-Paratyphoid Vaccines/*administration & dosage; Adolescent ; Adult ; Bacterial Proteins/genetics ; DNA, Bacterial/analysis ; Feces/microbiology ; Female ; Humans ; Immunoglobulin A/blood ; Immunoglobulin G/blood ; Lipopolysaccharides ; Male ; Middle Aged ; Salmonella typhi/genetics ; Salmonella typhi/isolation & purification ; Sequence Deletion ; Typhoid-Paratyphoid Vaccines/adverse effects ; Typhoid-Paratyphoid Vaccines/genetics ; Typhoid-Paratyphoid Vaccines/immunology ; Vaccination ; Vaccines, Attenuated/administration & dosage ; Vaccines, Attenuated/adverse effects ; Vaccines, Attenuated/immunology ; Vaccines, Synthetic/administration & dosage ; Vaccines, Synthetic/adverse effects ; Vaccines, Synthetic/immunology

The phoP/phoQ virulence regulatory genes of Salmonella typhi Ty2 were deleted, and the resultant strain (Ty800) was tested as a live attenuated typhoid fever vaccine in human volunteers. Groups of 2 or 3 subjects received single oral doses of 10(7), 10(8), 10(9), or 10(10) cfu. Two volunteers who received the largest dose had self-limited side effects; no bacteremias were detected. Ten of 11 subjects had evidence of intestinal immune responses to the vaccine as measured by increases in S. typhi lipopolysaccharide-specific IgA-secreting cells in peripheral blood samples. Humoral immune responses were measured and compared with those of control vaccinees who received 4 oral doses of S. typhi Ty21a. In the most sensitive assays, 9 of 11 volunteers and 5 of 8 Ty21a control vaccinees had evidence of IgG directed against S. typhi antigens. Ty800 is safe, and single oral doses are highly immunogenic in humans.

AI-30497 United States AI NIAID NIH HHS; DJ-01410 United States PHS HHS; RR-01066 United States RR NCRR NIH HHS

0 (Antibodies, Bacterial)
0 (Bacterial Proteins)
0 (DNA, Bacterial)
0 (Immunoglobulin A)
0 (Immunoglobulin G)
0 (Lipopolysaccharides)
0 (PhoQ protein, Bacteria)
0 (Typhoid-Paratyphoid Vaccines)
0 (Vaccines, Attenuated)
0 (Vaccines, Synthetic)
125360-99-8 (PhoP protein, Bacteria)

Date Created: 19960601 Date Completed: 19960725 Latest Revision: 20190512

20240829

10.1093/infdis/173.6.1408

8648213