High performance collection of cerebrospinal fluid in rats: evaluation of erythropoietin penetration after osmotic opening of the blood-brain barrier.

An important issue to be considered when studying a new drug for treatment of central nervous system (CNS) diseases is its ability to cross the blood-brain barrier (BBB) and distribute throughout the brain. As cerebrospinal fluid (CSF) has demonstrated to be an invaluable reservoir to study CNS availability of therapeutic proteins, we have developed an improved method for CSF sampling from the cisterna magna of rats. The technique enables the simple and rapid collection of adequate quantities (50-75 μl) of blood-free CSF, rendering a high percentage of animal survival (99%) without clinic or neurological consequences.

A versatile ionic strength sensitive tag from a human GM-CSF-derived linear epitope.

A 7-mer hGM-CSF-derived linear epitope (APARSPS) is herein described as a novel and small tag taking into account its particular binding affinity in native conditions that could be easily modified by increasing or lowering the ionic strength. Thus, a 3.4 or 3.

Isolation and characterization of a subset of erythropoietin glycoforms with cytoprotective but minimal erythropoietic activity.

Although historically used for the treatment of anemia, erythropoietin (EPO) has emerged as a neurotrophic and neuroprotective agent in different conditions of neuronal damage (traumatic brain injury, ischemia, spinal cord compression, peripheral neuropathy, retinal damage, epilepsy, Parkinson's Disease, among others). Nonetheless, EPO's therapeutic application is limited due to its hematological side-effects. With the aim of obtaining EPO derivatives resembling the hormone isolated from cells and tissues of neural origin, a novel combination of less acidic EPO glycoforms -designated as neuroepoetin (rhNEPO)- was purified to homogeneity from the supernatant of a CHO-producing cell line by a four-step chromatographic procedure.