Table 4 Secondary Endpoints

1. Absolute and relative change from baseline of cell-counts in the CSF at indicated time-points of sampling (see Additional file 1: Assessment Schedule). The same cell-types as indicated for the primary endpoints will be evaluated.

2. Functional characterization of T-cells in the peripheral blood and the CSF at indicated time-points of sampling (see Additional file 1: Assessment Schedule):

 a. Activation status of cell surface receptors assessed by flow cytometry: Relative and absolute change from baseline of mean fluorescence intensity (MFI) and of proportion of positive cells regarding CD25, HLA-DR, LFA-1, CD29, CD69, CD71 expression

 b. Expression of co-inhibitory molecules assessed by flow cytometry: Relative and absolute change from baseline of MFI and of proportion of positive cells regarding PD-1 = CD279, ICOS = CD278, TIM-3, CTLA4 expression

 c. Effector functions of CD4 and CD8 positive T cells:

  - Relative and absolute change from baseline of the results of cell proliferation assays assessed as percentage of proliferated cells

  - Relative and absolute change from baseline of cytokine production measurement assessed as concentration

  - Relative and absolute change from baseline of cytolytic activity assessed by flow cytometry measurement of MFI and proportion of positive cells regarding Granzyme B, Perforin and CD107a expression

  - Relative and absolute change from baseline of intracellular calcium response assessed as concentration

 d. Migrational capacity:

  - Relative and absolute change from baseline MFI and proportion of positive cells assessed by flow cytometry expression analysis of CD11a, CD31, CD44, CD49d, CCR5, CCR6, CCR7

  - Absolute and relative change of cell numbers of migrated cells compared to baseline assessed in an in vitro model by flow cytometry analysis

 e. Spectratyping of the T cell repertoire concerning the expansion of distinct clones:

  - Relative and absolute change from baseline for complexity scores

  - Qualitative comparison of the distribution of CDR3 sequences

 f. Regulatory T-cell function:

  - Relative and absolute change from baseline in production of TGF-beta and IL-10 of CD4⁺CD25⁺FOXP3⁺ regulatory T cells

  - Suppression of T cell proliferation: Relative and absolute change from baseline in responder T cell proliferation assessed by suppression assays