CD19 and periodontitis: Indeed, the co-expression of CD1d and CD19 on the same cells and proximate infiltration of CD1d+ and Vα24+ cells was observed in periodontitis-affected tissues, suggesting that CD1d+ B lymphocytes could activate Vα24+ NKT cells in a CD1d-restricted manner [83], being B lymphocytes largely present in the diseased gingival tissues infiltrate of periodontitis-affected patients [92].