CD28 and Alzheimer disease: To further investigate T cell differentiation in our AD mice, the levels of IFN-γ (Th1), IL-17 (Th17), IL-4 (Th2) and IL-10 (Th9) were measured in anti-CD3/CD28 activated T cells derived from the local LNs of the UC-MSC- or MSC-Ex-treated animals.