Yes, you may use E.coli to express interleukin peptide for you

In this publication, 

ARCONE R, PUCCI P, ZAPPACOSTA F, Fontaine V, MALORNI A, MARINO G, CILIBERTO G. Single‐step purification and structural characterization of human interleukin‐6 produced in Esherichia coli From a T7 RNA polymerase expression vector. European Journal of Biochemistry. 1991 Jun 1;198(3):541-7.

In the abstract, 

Cloning of cDNA for human interleukin-6 in the pT7.7 expression plasmid under the control of a bacteriophage T7 RNA polymerase promoter system allows rapid production of the cytokine in Escherichia coli. Upon cell induction with isopropyl thiogalactopyranoside, recombinant human interleukin-6 is overexpressed and forms insoluble inclusion bodies. Solubilization of the protein with 6 M guanidine hydrochloride and refolding in the presence of a reduction/oxidation system results in a quantitative recovery of recombinant human interleukin-6. This material is already 70% pure and can be further purified to homogeneity with a single passage over a weak anionic-exchange column. Extended structural characterization of the purified protein by electrospray mass spectrometry, automated Edman degradation and peptide mapping by high-pressure liquid chromatography/fastatom-bombardment mass spectrometry demonstrates that recombinant human interleukin-6 is identical to the natural protein both in amino acid sequence and S-S bridge content.

They also provide the recovery method for purification.  

Just take into account the total cost of the experiment: Gene synthesis, expression and purification, validation, possible failure, time and manpower.

Hi Luis,

from experience, IL1B and IL6 are readily purified as soluble proteins from E.coli at high yield - you can get in contact with me outside RG if interested as I don't want to post material here that could give the impression of a conflict of commercial interest on my part or that of my employer.  Best wishes,  Robin