gradual: (Roman Catholic Church) an antiphon (usually from the Book of Psalms) immediately after the epistle at Mass
antiphon: a verse or song to be chanted or sung in response
immunosuppression: lowering the body's normal immune response to invasion by foreign substances; can be deliberate (as in lowering the immune response to prevent rejection of a transplanted organ) or incidental (as a side effect of radiotherapy or chemotherapy for cancer)