Use of a novel antigen expressing system to study the Salmonella enterica serovar Typhi protein recognition by T cells
Year: 2017
Type: article
Abstract: Salmonella enterica serovar Typhi (S.Typhi), the causative agent of the typhoid fever, is a pathogen of great public health importance.Typhoid vaccines have the potential to be cost-effective measures towards combating this disease, yet the antigens triggering host protective immune responses are largely unknown.Given the key role of cellular-mediated immunity in S. Typhi protection, it is crucial to identify S. Typhi proteins involved in T-cell responses.Here, cells from individuals immunized with Ty21a typhoid vaccine were collected before and after immunization and used as effectors.We also used an innovative antigen expressing system based on the infection of B-cells with recombinant Escherichia coli (E.coli) expressing one of four S. Typhi gene products (i.e., SifA, OmpC, FliC, GroEL) as targets.Using flow cytometry, we found that the pattern of response to specific S. Typhi proteins was variable.Some individuals responded to all four proteins while others responded to only one or two proteins.We next evaluated whether T-cells responding to recombinant E. coli also possess the ability to respond to purified proteins.We observed that CD4 + cell responses, but not CD8 + cell responses, to recombinant E. coli were significantly associated with the responses to purified proteins.Thus, our results demonstrate the feasibility of using an E. coli expressing system to uncover the antigen specificity of T-cells and highlight its applicability to vaccine studies.These results also emphasize the importance of selecting the stimuli appropriately when evaluating CD4 + and CD8 + cell responses. Author summarySalmonella enterica serovar Typhi (S.Typhi) is the causative agent of the life-threatening typhoid fever that affects 11.9-20.6 million individuals annually in low-income and middle-income countries.The T-cells, CD4 + and CD8 + T cells, play a significant role in protection against S. Typhi infection.Yet, the antigens triggering host protective immune
Source: PLoS neglected tropical diseases
Language: English
Subfield: Food Science
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,670
Awards: G1106154561, G1775776426, G253821769, G2794449220, G4323153164, Immunoprophylactic Strategies to Control Emerging Enteric Infections, G6476134810, G6561746670, G6939976566, G753873811, Immune Mechanisms of Protection in S. Typhi Infection and Vaccination in Humans, Mucusal and Systemic Immunity, Vaccines and Microbiota Interplay in Humans, G9000007769, G9000165242
OpenAlex ID: W2751532363