A chicken bioreactor for efficient production of functional cytokines.

BACKGROUND: The global market for protein drugs has the highest compound annual growth rate of any pharmaceutical class but their availability, especially outside of the US market, is compromised by the high cost of manufacture and validation compared to traditional chemical drugs. Improvements in transgenic technologies allow valuable proteins to be produced by genetically-modified animals; several therapeutic proteins from such animal bioreactors are already on the market after successful clinical trials and regulatory approval. Chickens have lagged behind mammals in bioreactor development, despite a number of potential advantages, due to the historic difficulty in producing transgenic birds, but the production of therapeutic proteins in egg white of transgenic chickens would substantially lower costs across the entire production cycle compared to traditional cell culture-based production systems. This could lead to more affordable treatments and wider markets, including in developing countries and for animal health applications. RESULTS: Here we report the efficient generation of new transgenic chicken lines to optimize protein production in eggs. As proof-of-concept, we describe the expression, purification and functional characterization of three pharmaceutical proteins, the human cytokine interferon α2a and two species-specific Fc fusions of the cytokine CSF1. CONCLUSION: Our work optimizes and validates a transgenic chicken system for the cost-effective production of pure, high quality, biologically active protein for therapeutics and other applications.

Do the results of the new trials change the standard treatment of metastatic renal cell cancer?

With the emergence of novel angiogenesis inhibitors, we are moving to a new era for patients with metastasized renal cell carcinoma. Since the results achieved reflect more a modification of the natural course of the disease than a cure, past achievements should not be neglected. Low-risk patients with clear cell histology, especially those with pulmonary metastasis only, should still be offered cytokine therapy. For intermediate-risk patients sunitinib is the treatment of choice. For high-risk patients, temsirolimus has to date provided the most convincing data, its availability is however limited. Data with sorafenib and sunitinib in the high-risk group are still anecdotal. The toxicity profiles of these 2 drugs are different and might particularly relate to patients with known cardiovascular co-morbidity. No sufficient data are available regarding sequential use. After cytokine failure, sorafinib is the treatment of choice. Patients should preferably be treated within clinical trials to answer unaddressed questions. It is well known that the strict entry criteria used within the clinical studies were applied very flexibly when drugs have been approved. These aspects require a careful follow-up to ascertain optimal use and to prevent misuse. Finally, the costs of prolonged treatment will be enormous, and only meaningful survival advantages will convince the health authorities to make these new treatments available for all patients.

Rheumatoid arthritis: regulation of synovial inflammation.

Rheumatoid arthritis (RA) is a systemic, inflammatory autoimmune disorder that presents as a symmetric polyarthritis associated with swelling and pain in multiple joints, often initially occurring in the joints of the hands and feet. Articular inflammation causes activation and proliferation of the synovial lining, expression of inflammatory cytokines, chemokine-mediated recruitment of additional inflammatory cells, as well as B cell activation with autoantibody production. A vicious cycle of altered cytokine and signal transduction pathways and inhibition of programmed cell death contribute to synoviocyte and osteoclast mediated cartilage and bone destruction. A combination of targeted interventions at various stages in the pathogenesis of RA will likely be required to control symptoms in certain patients with this complex and potentially disabling disease. The regulation of rheumatoid synovial inflammation will be reviewed, followed by a brief summary of the therapeutic implications of these advances, including strategies targeting key cytokines, signal transduction molecules, co-stimulatory molecules, B cells, chemokines, and adhesion molecules.

Mobilization, collection, and processing of autologous peripheral blood stem cells: development of a clinical process with associated costs.

We surveyed five academic medical centers to develop a clinical process for patients undergoing cytokine mobilization and leukapheresis prior to autologous peripheral blood stem cell transplantation. Costs were obtained from three centers and applied to each component of the pathway. Costs were divided into three categories: (1) pre-apheresis evaluation; (2) process of apheresis; (3) post-apheresis and peripheral blood stem cells processing. All centers participated in the development of the leukapheresis pathway. Because charges vary greatly among institutions, costs were determined from three of the institutions and a mean was calculated for each of the components of the process. Pre-apheresis costs consisted of central line placement, blood work, and the price of cytokine (rhG-CSF). Costs associated with apheresis included professional fees (for physicians and nurses), leukapheresis with stem cell cryopreservation, storage, sterility testing, analysis of circulating CD34+ cell counts, and 1 day of cytokine therapy. The post-apheresis process included thawing with sterility testing along with CD34+ cell number analysis and the performance of clonogenic assays. Total costs were as follows: (1) pre-apheresis, $2711; (2) apheresis, $2990; and, (3) post-apheresis/stem cell processing, $754. This survey from five academic medical centers provides the average costs associated with three main components of the apheresis procedure. Because many patients require multiple aphereses, interventions to achieve target CD34+ cell collections in as few collections as possible would result in significant cost reduction.

[The cost of cytokines]. / Le coût des cytokines.

The use of cytokines (interferons, interleukin-2, growth factors) is in full development, but the new drugs issued from biotechnology are costly. In order to control consumption, these products are made available only to hospital pharmacists, and they are paid by the prescribing establishments from global funds. This results in an ever growing financial burden on the hospital pharmaceutical budget. Physicians will have to conciliate 2 objectives: make the patients benefit from the new drugs, and control the expenses by using these drugs only when necessary.