Previous observational studies showed that high-dose and long-term glucocorticoid therapy and low LYMP count in non-HIV and non-organ transplant patients were highly associated with PCP.[54–58] A study showed a decrease in the percentage of CD4+, CD4+/CD8 + ratios and NK cell in patients with Cushing’s syndrome compared to controls.[59] The stimulating signals from dendritic cells (DCs) are the beginning of T cell mediated adaptive immune response. Here, CD8A is linked to Cushing syndrome.