Mammalian cell expression systems are currently essential for production of glycosylated biopharmaceuticals such as monoclonal antibodies or molecules requiring even more complex glycan structures. Various host cell and vector systems aimed at improving expression levels and quality have been established (1, 2). Development of biopharmaceutical product candidates from genes to clinical trials s...

Lewis X trisaccharides normally function as essential cell-cell interaction mediators. However, oligomers of Lewis X trisaccharides expressed by the parasite Schistosoma mansoni seem to be related to its evasion of the immune response of its human host. Here we show that monoclonal antibody 54-5C10-A, which is used to diagnose schistosomiasis in humans, interacts with oligomers of at least thre...

We have examined the low-resolution structure of a complete human IgG1 using known domain coordinates from crystallographic investigations of immunoglobulin fragment structures. Our results indicate that the Fc portion of this molecule has a structure similar to that of an isolated Fc fragment, with the carbohydrate moiety playing a central role as the principal contact between the CH2 domains....

The crystal structure of the Michaelis complex between the Fab fragment of ferrochelatase antibody 7G12 and its substrate mesoporphyrin has been solved to 2.6-A resolution. The antibody-bound mesoporphyrin clearly adopts a nonplanar conformation and reveals that the antibody catalyzes the porphyrin metallation reaction by straining/distorting the bound substrate toward the transition-state conf...

The IgG molecule, like all antibodies, is a glycoprotein, and with the discovery in 1959 that the rabbit IgG molecule could be split by the action of papain into two Fab (antigen-binding) and one Fc (crystallizable, complementand cell-binding) fragment, the major glycosylation site was found to lie within Fc (Porter, 1959). (The Fc fragment conists of the C-terminal half of each of the two ‘hea...

Combined therapy emerges as an attractive strategy for cancer treatment. The aim of this study was to investigate the inhibitory effects of mitomycin C (MMC) combined with a novel antibody fragment (Fab) targeting latent membrane protein 1 (LMP1) on nasopharyngeal carcinoma (NPC) xenograft nude mice. The inhibitory rates of MMC (2 mg/kg), Fab (4 mg/kg), MMC (2 mg/kg) + Fab (4 mg/kg), and MMC (1...

7C8 is a mouse monoclonal antibody specific for the third hypervariable region (V3) of the human immunodeficiency virus type 2 (HIV-2)-associated protein gp125. The three-dimensional crystal structure of the Fab fragment of 7C8, determined to 2.7 Å resolution, reveals a deep and narrow antigen-binding cleft with architecture appropriate for an elongated epitope. The highly hydrophobic cleft is ...

Antibodies are critical components of the human adaptive immune system, providing versatile scaffolds to display diverse antigen-binding surfaces. Nevertheless, most antibodies have similar architectures, with the variable immunoglobulin domains of the heavy and light chain each providing three hypervariable loops, which are varied to generate diversity. The recent identification of a novel cla...

N-terminal fragment of emerimicin III has been synthesized by the repetitive method in solution, involving triazine ,,superactive esters". The synthetic protocol, equivalent to the classic REMA procedure, has been applied in the step by step approach, and in the fragment coupling affording all the peptide bonds. By monitoring the progress of the synthesis by FAB-MS, 1H-NMR and HPLC, the structu...