In our cohort, pooled HD patients on anti-CD20 therapy showed tendentiously lower number of SARS-CoV-2 reactive CD4+ T-cells compared to HD patients with no anti-CD20 treatment (Figures 4A–C) and this result was further confirmed by the reduced or zero % of patients on anti-CD20 achieving the cut-off value of 400 responding CD4 T-cells in a million (data not shown). This evidence concerns the gene CD4 and Huntington disease.