Journal: bioRxiv

Article Title: Immunotherapy of cytomegalovirus infection by low-dose adoptive transfer of antiviral CD8 T cells relies on substantial post-transfer expansion of central memory cells but not effector-memory cells

doi: 10.1101/2023.08.31.555660

Figure Lengend Snippet: (A) Frequencies of viral epitope-specific TCM, iTEM, and cTEM. (Left panel) IE1 peptide-specific cells. (Right panel) m164 peptide-specific cells. Frequencies refer to functional cells responding with secretion of IFNγ in an ELISpot assay to stimulation by P815 cells loaded with the respective antigenic peptide at the saturating concentration of 10 -8 M. (NP) no peptide. (B) Cumulative avidity distributions and deduced Gaussian-like avidity distributions of TCM, iTEM, and cTEM specific for antigenic peptides IE1 and m164, corresponding to (A). Stimulator cells in the ELISpot assay were P815 cells loaded with the respective antigenic peptide in the graded concentrations indicated. (NP) no peptide. (EC 50 and 95% CI) effective concentration and its 95% confidence interval of antigenic peptide that leads to the half-maximal response of the CD8 T-cell population tested. Throughout, bars represent frequencies determined by intercept-free linear regression analysis. Error bars represent the 95% confidence intervals. Data for transferred CD8 T-cell subsets are color-coded as defined in .

Article Snippet: Based on MPN and the corresponding upper and lower 95% confidence limits, half-maximal effective concentration (EC 50 ) values, representing peptide concentrations that result in the half-maximal response of the cell population, were calculated with Quest Graph™ EC 50 Calculator (AAT Bioquest, Inc.; retrieved from https://www.aatbio.com/tools/ec50-calculator ).

Techniques: Functional Assay, Enzyme-linked Immunospot, Concentration Assay

Journal: bioRxiv

Article Title: Strong SARS-CoV-2 N-specific CD8 + T immunity induced by engineered extracellular vesicles associates with protection from lethal infection in mice

doi: 10.1101/2022.01.10.475620

Figure Lengend Snippet: Antiviral effect induced by high levels of N-specific CD8 + T cell immunity. ( A ) CD8 + T cell immune response in C57 Bl/6 K18-hACE-2 mice injected with vectors expressing either Nef mut /S1, Nef mut /N or, as control, Nef mut alone. PBMCs were isolated by retro orbital bleeding and, after erythrocyte lysis, were incubated o.n. with or without 5 μg/mL of either unrelated or SARS-CoV-2 related peptides in triplicate IFN-γ EliSpot microwells. Shown are the number of SFUs/10 5 PBMCs as mean values of triplicates after subtraction of values from wells treated with an unrelated peptide. Intragroup mean values + SD are reported. ( B ) Kaplan–Meier survival curve calculated for groups of C57 Bl/6 K18-hACE-2 mice infected with 4.4 LD 50 of SARS-CoV-2. Differences between Kaplan-Meier survival curves relative to S1- and N-immunized groups of mice were statistically significant (log-rank test, p = 0.01285). ( C ) Relative weight loss in each injected mice after SARS-CoV-2 challenge. Identification numbers of each mouse are reported on the right of each panel. SFUs/10 5 PBMCs for each low and high responder N-immunized mouse are also indicated together with intergroup mean values. Shown are cumulative data from two experiments.

Article Snippet: For the in vivo titration, virus dilutions and number of deaths/group after challenge were used to calculate the LD 50 (Quest Graph™ LD 50 Calculator, AAT Bioquest, Inc.).

Techniques: Injection, Expressing, Isolation, Lysis, Incubation, Enzyme-linked Immunospot, Infection

Journal: bioRxiv

Article Title: Strong SARS-CoV-2 N-specific CD8 + T immunity induced by engineered extracellular vesicles associates with protection from lethal infection in mice

doi: 10.1101/2022.01.10.475620

Figure Lengend Snippet: Relative weight loss in mice injected with 10 μg each of Nef mut /S1, Nef mut /S2 and Nef mut /N expressing vectors, and then infected with 5 LD 50 of SARS-CoV-2. Identification numbers for each mouse are reported on the right together with the counts of SFUs/10 5 PBMCs after incubation with the N 219-228 peptide. S2-specific SFU counts as measured using a pool of S2 peptides were similar in each mouse.

Article Snippet: For the in vivo titration, virus dilutions and number of deaths/group after challenge were used to calculate the LD 50 (Quest Graph™ LD 50 Calculator, AAT Bioquest, Inc.).

Techniques: Injection, Expressing, Infection, Incubation