An early commitment to expression of a particular TCRV beta chain on CD8+T cells responding to attenuated Plasmodium berghei sporozoites is maintained following challenge with infectious sporozoites

作者：Lumsden J M; Cranmer M A; Krzych U^*

来源：Parasite Immunology, 2010, 32(9-10): 644-655.

DOI：10.1111/j.1365-3024.2010.01220.x

• CD8+T cells
• liver stage
• malaria
• mouse
• Plasmodium berghei
• TCR V beta repertoire

P>Protection induced by irradiated Plasmodium berghei sporozoites (Pb gamma-spz) in mice is linked to CD8+ T cells specific for exo-erythrocytic-stage Ags, and intrahepatic memory CD8+ T cells are associated with protracted protection. However, the Ag specificity of the protective CD8+ T cells remains largely unknown. In this study, we characterized the TCR V beta usage by intrahepatic CD8+ T cells during gamma-spz immunization and after the challenge with infectious Pb sporozoites. The repertoire of naive (T(N)) and central memory (T(CM)) CD8+ T cells was diverse and conserved between individual mice, and did not change with immunization. In contrast, preferential usage of one or more TCR V beta subset was observed in effector memory (T(EM)) CD8+ T cells after immunization. The expanded TCR V beta varied between individual mice but V beta 4, 6, 7, 8.3, 9 and 11 were the most frequently expressed. In addition, there was a correlation in the TCR V beta usage by gamma-spz-induced CD8+ T(EM) in the liver and blood of individual mice. The expansion pattern of blood CD8+ T(EM) did not change with challenge and remained the same for 8 weeks thereafter. These results demonstrate that immunization with gamma-spz skews the TCR V beta repertoire of CD8+ T(EM), and commitment to a particular TCR V beta expression is maintained long-term.

• 出版日期2010-10