Based on synonyms in MeSH and EMTREE databases and assuming hyphenated terms will retrieve hyphenated terms as well as those with spaces.
il-1 OR il1 OR interleukin-i OR interleukin-1 OR LAF OR leucocyte-pyrogen OR leukocyte-pyrogen OR leucocytic-endogenous-mediator OR leukocytic-endogenous-mediator OR leukocytic-pyrogen OR leucocytic-pyrogen OR lymphocyte-activating-factor OR T-Helper-Factor OR Lymphocyte-Activating-Factor OR Macrophage-Cell-Factor OR Epidermal-Cell-Derived-Thymocyte-Activating-Factor
