The building blocks of English

Affixes

immuno-

Immune or immunity.

English immune plus ‑o‑.

Immunology is the branch of medicine and biology concerned with immunity; a drug that is immunosuppressive partially or completely suppresses the immune response of an individual; a substance that is immunogenic is able to produce an immune response; immunodeficiency, as in the human immunodeficiency virus (HIV), is failure of the immune system to protect the body adequately from infection; an immunoglobulin is one of a class of proteins present in the serum and cells of the immune system, which function as antibodies.