Featured herein are non naturally occuring cytokine domains that can be used to modulate cellular signalling responsive to interleukin 1 receptor I (IL 1 RI) to treat disorders and to detect and/or bind to cellular receptors as well as other agents. Exemplary cytokine domains can contain amino acid residues from at least two parental cytokines domains for example receptor binding features surface features strands and loops from at least two parental cytokines domains.