Annotating genes with potential roles in the immune system: six new members of them IL-1 family

Analysis of the human genome sequence and other DNA databases is proceeding at a rapid pace, and immunologists are playing an important role in the ef fort to ascribe functions to putative gene products. An excellent, recent e xample is the description of six gene sequences predicted to encode homolog s of interleukin-1 (IL-1), named IL-1F5-IL-1F10. Indications of a possible role for these homologs in immunity and inflammation are starting to emerge . Most are expressed in monocytes, macrophages and/or dendritic cells; IL-1 F5 and IL-1F9 are expressed strongly in keratinocytes; and the expression o f IL-1F9 is induced in skin during contact hypersensitivity and in psoriasi s patients. IL-1F7 and IL-1F10 bind to the soluble type I IL-1 receptor (IL -1RI) and IL-18R, respectively. Specific functions for these proteins are c urrently being sought.