Novel mutants of human tumor necrosis factor with dominant-negative properties

Production of anti TNF-α antibodies in eukaryotic cells using different combinations of vectors carrying heavy and light chains

Tumor necrosis factor-α (TNF-α) plays a key role in rheumatoid arthritis and some other autoimmune diseases. Therapy with anti-TNF-α recombinant antibodies (Ab) appears to be highly effective. Production of new hyper-producing eukaryotic cell lines can decrease the treatment cost, which currently is very high. However, due to the complexity of protein transcription, translation, processing, and secretion in mammalian cells, the stages at which antibody expression is affected are still poorly determined. The aim of this work was to compare the productivity of two cell lines developed in CHO DG44 cells, deficient in dihydrofolate reductase, transfected with vectors carrying either heavy (H) or light (L) chains of chimeric antibody under different combinations of selective elements. Both H and L chains were cloned either in pOptiVEC or pcDNA3.3 vectors and different combinations were used to produce HL and LH cell lines. We have shown that Ab production has been low and comparable between HL and LH cells until selection on methotrexate (MTX) when LH but not HL cells have responded with 3.5 times increased productivity. Flow cytometry analysis has demonstrated that intracellular concentration of full size Abs in LH cells was 5.6 times higher than in HL ones due to higher amount of H chain synthesis. No differences in viability between HL and LH cells have been found. We have concluded that the expression of H chain in the pOptiVEC vector, which is responsible for MTX resistance, has led to the suppression of H chain synthesis and limitation in full Ab assembly.

Is there any relation between cervical cord plaques and discopathy in patients with multiple sclerosis?

INTRODUCTION

Multiple sclerosis (MS) is the most common chronic autoimmune demyelinating disease of the central nervous system. The purpose of this study is to determine the relationship between the site of the cervical discopathy and cervical spinal cord plaque in MS patients.

METHODS

This retrospective study included all patients with a definite diagnosis of MS who were treated at an outpatient clinic between September 2004 and September 2011. All patients underwent cervical magnetic resonance imaging (MRI) for primary investigation of the disease. Cervical MRI scans were evaluated for detection of any evidence of cervical discopathy and cervical MS plaques. Any correlation between the site of the MS lesions and discopathy was recorded.

RESULTS

From 536 patients who were involved in the study, 214 patients had both cervical discopathy and cervical cord plaques. In this group 148 (69.1% of patients) had cervical plaque at the same site of cervical discopathy. The number of patients with cervical cord plaque and discopathy at same site was significantly higher than those with plaque and discopathy at different sites (P<0.05).

CONCLUSION

The study data suggests a possible correlation between cervical discopathy and cervical MS plaque.