Monoclonal antibody fragment removal mediated by mixed mode resins.

Efforts to increase monoclonal antibody expression in cell culture can result in the presence of fragmented species requiring removal in downstream processing. Capto adhere, HEA Hypercel, and PPA Hypercel anion exchange/hydrophobic interaction mixed mode resins were evaluated for their fragment removal capabilities and found to separate large hinge IgG1 antibody fragment (LHF) from monomer. Removal of greater than 75% of LHF population occurred at pH 8 and low conductivity.

A Therapeutic Uricase with Reduced Immunogenicity Risk and Improved Development Properties.

Humans and higher primates are unique in that they lack uricase, the enzyme capable of oxidizing uric acid. As a consequence of this enzyme deficiency, humans have high serum uric acid levels. In some people, uric acid levels rise above the solubility limit resulting in crystallization in joints, acute inflammation in response to those crystals causes severe pain; a condition known as gout.

Developmental toxicity of 2-ethylhexyl stearate.

2-Ethylhexyl stearate was investigated in an embryo-/foetotoxicity and teratogenicity study on rats according to OECD guidelines for the testing of chemicals (No. 414). Dose levels of 0 (arachidis oil), 100, 300 and 1000mg/kg body weight/day were administered by gavage.

Comparison of two in vitro and two in vivo methods for the measurement of irritancy.

A number of in vitro assays have recently been developed that need further validation in order to judge their value for local tolerance testing. For this purpose, results from the following experiments were compared: (A) cytotoxicity testing in cell culture (neutral red assay); (B) tests with the chorioallantoic membrane of fertilized chicken eggs; (C) rabbit eye mucous membrane tests; and (D) occluded epicutaneous testing in human volunteers. The data presented indicate that in vitro testing with the first two methods yields reliable results with respect to the eye and human skin irritation data within homologous substance classes.

Skin organ culture for the study of skin irritancy.

Skin explants maintained in culture may represent a reliable model for in vitro tests of the irritancy of chemicals. During the process of skin irritation intracellular enzymes migrate into the culture medium. The amount of released enzyme activity corresponds to the degree of skin damage.

Percutaneous absorption, metabolism, and hemolytic activity of n-butoxyethanol.

A series of studies was conducted to examine the percutaneous absorption, distribution, excretion, and hemolytic activity of n-butoxyethanol (BE). Rats receiving a subcutaneous dose of 14C-labeled BE excreted the radioactivity in the urine (79%), expired air (10%), and feces (0.5%) within 72 hr.

Percutaneous absorption of formaldehyde in rats.

As formaldehyde is used as a preservative in cosmetic products, its dermal absorption from an O/W-cream was studied using rats. [14C]Formaldehyde as a tracer, together with non-labelled formaldehyde, was incorporated into a cream at a total concentration of 0.1%.

Zeolithe A--A phosphate substitute for detergents: toxicological investigation.

Tests on Zeolithe A, a sodium aluminium silicate developed as a substitute for phosphates in detergents, were designed to investigate the safety of exposure to the material, or to detergents containing it, either under industrial conditions encountered during manufacturing processes or as a consequence of domestic use. The test programme included oral studies (acute, subchronic and long-term carcinogenicity tests and absorption measurements), and dermal, ocular and inhalation studies on the silicate alone and on appropriate detergent formulations, as well as studies of possible silicogenic activity and metal-complexing potential and measurements of dust generation and particle-size distribution. These studies did not produce any evidence to suggest that levels of domestic and industrial exposure resulting from the projected use of Zeolithe A in detergents would present any hazard to health.