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SelectedWorks

Microbiology

2003

Articles 1 - 4 of 4

Full-Text Articles in Life Sciences

Cd43 Modulates Severity And Onset Of Experimental Autoimmune Encephalomyelitis., Thandi M. Onami, M. L. Ford, A. Sperling, R. Ahmed, B. D. Evavold Dec 2003

Cd43 Modulates Severity And Onset Of Experimental Autoimmune Encephalomyelitis., Thandi M. Onami, M. L. Ford, A. Sperling, R. Ahmed, B. D. Evavold

Thandi M. Onami

Experimental autoimmune encephalomyelitis (EAE) is a mouse model of multiple sclerosis characterized by infiltration of activated CD4(+) T lymphocytes into tissues of the CNS. This study investigated the role of CD43 in the induction and progression of EAE. Results demonstrate that CD43-deficient mice have reduced and delayed clinical and histological disease severity relative to CD43(+/+) mice. This reduction was characterized by decreased CD4(+) T cell infiltration of the CNS of CD43(-/-) mice but similar numbers of Ag-specific T cells in the periphery, suggesting a defect in T cell trafficking to the CNS. The absence of CD43 also affected cytokine production, …


Primary And Secondary Immunocompetence In Mixed Allogeneic Chimeras, Thandi M. Onami, M. A. Williams, A. B. Adams, M. B. Walsh, N. Shirasugi, T. C. Pearson, R. Ahmed, C. P. Larsen Mar 2003

Primary And Secondary Immunocompetence In Mixed Allogeneic Chimeras, Thandi M. Onami, M. A. Williams, A. B. Adams, M. B. Walsh, N. Shirasugi, T. C. Pearson, R. Ahmed, C. P. Larsen

Thandi M. Onami

Targeted disruption of T cell costimulatory pathways, particularly CD28 and CD40, has allowed for the development of minimally myeloablative strategies for the induction of mixed allogeneic chimerism and donor-specific tolerance across full MHC barriers. In this study we analyze in depth the ability of mixed allogeneic chimeras in two strain combinations to mount effective host-restricted and donor-restricted antiviral CD4 and CD8 responses, as well as the impact of development of mixed chimerism on the maintenance of pre-existing memory populations. While antiviral CD8 responses in mixed chimeras following acute viral infection with lymphocytic choriomeningitis virus Armstrong or vaccinia virus are largely …


Further Evaluation Of A Multiplex Pcr For Differentiation Of Salmonella Paratyphi A From Other Salmonellae, Thong Kwai Lin Jan 2003

Further Evaluation Of A Multiplex Pcr For Differentiation Of Salmonella Paratyphi A From Other Salmonellae, Thong Kwai Lin

Thong Kwai Lin

Salmonella enterica serovar Paratyphi A is a causative agent of paratyphoid fever. The clinical syndrome caused by paratyphoid fever overlaps with other febrile illnesses and cannot be distinguished from typhoid fever. Conventional methods used for diagnosis are time consuming, costly, and labor-intensive. We evaluated the specificity, sensitivity, and application of a multiplex polymerase chain reaction (PCR) previously developed by the method (Ou, H.Y, Teh, C.S.J., Thong, K.L., et al., J. Mol. Diagn., 9, 624-630, 2007) using 6 S. Paratyphi A, 22 S. Typhi, and 85 other Salmonella serovars as well as 36 non-Salmonella strains. The detection limit of the multiplex …


Tcr Signal Transduction In Antigen-Specific Memory Cd8 T Cells, Thandi M. Onami, Ellen N. Kersh, Susan M. Kaech, Miriana Moran, E. John Wherry, M. Carrie Miceli, Rafi Ahmed Jan 2003

Tcr Signal Transduction In Antigen-Specific Memory Cd8 T Cells, Thandi M. Onami, Ellen N. Kersh, Susan M. Kaech, Miriana Moran, E. John Wherry, M. Carrie Miceli, Rafi Ahmed

Thandi M. Onami

Memory T cells are more responsive to Ag than naive cells. To determine whether memory T cells also have more efficient TCR signaling, we compared naive, effector, and memory CD8 T cells of the same antigenic specificity. Surprisingly, initial CD3 signaling events are indistinguishable. However, memory T cells have more extensive lipid rafts with higher phosphoprotein content before TCR engagement. Upon activation in vivo, they more efficiently induce phosphorylation of-LAT (linker for activation of T cells), ERK (extracellular signal-regulated kinase), JNK (c-Jun N-terminal kinase), and p38. Thus, memory CD8 T cells do not increase their TCR sensitivity, but are better …