(362d) Crossflow Microfiltration of E.Coli Cell Lysate Containing Inclusion Bodies of Recombinant Human Growth Hormone (Met-Hgh)

The production
of recombinant protein therapeutics as inclusion bodies has the main advantage
of high specific cellular yield.  The desired protein, mainly in the inactive
form (i.e. as inclusion bodies), has to be solubilized and refolded to high
yields and activity and at high purity.  Membrane-based separations namely,
microfiltration and ultrafiltration, provide an attractive method for the
recovery and concentration of inclusion bodies prior to subsequent refolding
steps.

This work describes the comparison
of a linear hollow fiber membrane module (a currently used technology) and a
helical hollow fiber membrane module (representing the latest self-cleaning
methodology based on Dean vortices) for cross flow microfiltration (MF) of an E.Coli
cell lysate containing recombinant human growth hormone (Met-hGH) inclusion
bodies. Polyethersulfone membranes (mean pore size 0.1 μm) were used for
all experiments. Diafiltration experiments were conducted to study the effect
of flux with number of diavolumes for the two modules. The helical module
exhibited improved performance as compared with the linear module with regards
to the permeation flux.  As the cell lysate is a complex mixture of cell
debris, soluble proteins and inclusion bodies, the back transport velocities of
these various entities in the feed become important during filtration. Thus it is
imperative to also study the effect of the wall shear rate on permeate flux.
This would give a better understanding of the operating conditions needed to
select for recovery of the Met-hGH inclusion bodies in high yield and purity.