CCR6 and Huntington disease: PCA analysis of the overall counts of lymphocyte immune cell populations, including expression of chemokine receptors and of markers of activation (e.g., CD25, HLA-DR, CXCR5, CCR6, Ki67), showed that the COVID group segregated distinctly, whereas LC patients were separately distributed and in close proximity of HD and Recovered individuals, with the latter two groups being comparably distributed (Figure 5A).