[5][6] This gene was identified by the induction of its expression in B lymphocytes by Epstein–Barr virus infection.

The protein encoded by this gene is a secreted glycoprotein, which is a member of the hematopoietin receptor family related to the p40 subunit of interleukin 12 (IL-12).

It plays a role in regulating cell-mediated immune responses.

[8] IL35, an inhibitory cytokine involved in regulatory T-cell function, is composed of EBI3 and the p35 subunit of IL12.

This article on a gene on human chromosome 19 is a stub.