biostudies-literatureMani RNIAID NIH HHS105182https://www.ebi.ac.uk/biostudies/studies/S-EPMC12371382biostudies-literatureUnknown25(8)CD8⁺ T cells from HLA-A2.1-transgenic mice, but not wild-type mice, immunized with the amino-terminus region (aa 41-152) of dense granule protein 6 (GRA6Nt) of Toxoplasma gondii secreted large amounts of perforin and granzyme B in response to GRA6Nt through antigen presentation by HLA-A2.1 in vitro. When those CD8⁺ T cells were transferred into chronically infected HLA-A2.1-expressing NSG mice deficient in T cells, cerebral cyst burden of the recipients of HLA-A2.1-transgenic T cells, but not of WT T cells, became significantly less than that of control mice with no cell transfer. Furthermore, the significant reduction of the cyst burden by a transfer of the HLA-A2.1-transgenic CD8⁺ immune T cells required an expression of HLA-A2.1 in the recipient NSG mice. Thus, antigen presentation of GRA6Nt by human HLA-A2.1is able to activate anti-cyst CD8⁺ T cells that eliminate T. gondii cysts through antigen presentation by human HLA-A2.1.Microbes and infectionImmunization with the amino-terminus region of dense granule protein 6 (GRA6) of Toxoplasma gondii activates CD8<sup>+</sup> cytotoxic T cells capable of removing tissue cysts of the parasite through antigen presentation by human HLA-A2.1.PMC12371382AI136821R01 AI095032R56 AI152597R21 AI136821AI152597R21 AI134323Delauw MFSuzuki YMercier CMani RfalseImmunization with the amino-terminus region of dense granule protein 6 (GRA6) of Toxoplasma gondii activates CD8<sup>+</sup> cytotoxic T cells capable of removing tissue cysts of the parasite through antigen presentation by human HLA-A2.1.CD8⁺ T cells from HLA-A2.1-transgenic mice, but not wild-type mice, immunized with the amino-terminus region (aa 41-152) of dense granule protein 6 (GRA6Nt) of Toxoplasma gondii secreted large amounts of perforin and granzyme B in response to GRA6Nt through antigen presentation by HLA-A2.1 in vitro. When those CD8⁺ T cells were transferred into chronically infected HLA-A2.1-expressing NSG mice deficient in T cells, cerebral cyst burden of the recipients of HLA-A2.1-transgenic T cells, but not of WT T cells, became significantly less than that of control mice with no cell transfer. Furthermore, the significant reduction of the cyst burden by a transfer of the HLA-A2.1-transgenic CD8⁺ immune T cells required an expression of HLA-A2.1 in the recipient NSG mice. Thus, antigen presentation of GRA6Nt by human HLA-A2.1is able to activate anti-cyst CD8⁺ T cells that eliminate T. gondii cysts through antigen presentation by human HLA-A2.1.2023-01-01T00:00:00Z2023 Nov-Dec2026-05-08T06:51:15.258Z2026-04-07T23:31:02.959ZS-EPMC123713823742332610.1016/j.micinf.2023.105182