该基因编码一种与I型干扰素和IL-10家族有远亲关系的细胞因子。这个基因，白细胞介素28a（il28a）和白细胞介素29（il29）是三个密切相关的细胞因子基因，它们在一个定位于19q13的染色体区域上形成一个细胞因子基因簇。病毒感染可诱导这三个基因所编码的细胞因子的表达。这三种细胞因子都与一种异二聚体ii类细胞因子受体相互作用，后者由白细胞介素10受体β（il10rb）和白细胞介素28受体α（il28ra）组成。[由RefSeq提供，2008年7月]
This gene encodes a cytokine distantly related to type I interferons and the IL-10 family. This gene, interleukin 28A (IL28A), and interleukin 29 (IL29) are three closely related cytokine genes that form a cytokine gene cluster on a chromosomal region mapped to 19q13. Expression of the cytokines encoded by the three genes can be induced by viral infection. All three cytokines have been shown to interact with a heterodimeric class II cytokine receptor that consists of interleukin 10 receptor, beta (IL10RB) and interleukin 28 receptor, alpha (IL28RA). [provided by RefSeq, Jul 2008]