ABSTRACT
One of the auto-antigens aberrantly targeted in Multiple sclerosis is myelin basic protein (MBP). In this study, chronic progressive multiple sclerosis (CPMS) patients receiving the experimental drug MBP8298, on a compassionate care trial, were examined before and after high dose peptide treatment for their circulating regulatory T-cell numbers and their responses to the common mitogens, phytohemagglutinin and poke-weed mitogen. Peripheral blood mononuclear cells (PBMCs) isolated from these patients before treatment displayed anergy upon stimulation with phytohemagglutinin; measured through reduced proliferation, IFN-γ and IL-17A secretion in an in vitro cell culture system. 6 Weeks and 6months after treatment their PBMCs displayed a reversal of anergy with phytohemagglutinin stimulation. There was also a marked increase in their CD4(+)CD25(+hi)FoxP3(+) T-cells regulatory T-cells. These results suggest that high dose MBP8298 treatment has a profound effect on the circulating T-cells of CPMS patients, capable of reversing peripheral anergy and establishing T regulation.
Subject(s)
Immunotherapy , Multiple Sclerosis, Chronic Progressive/drug therapy , Myelin Basic Protein/therapeutic use , Peptide Fragments/therapeutic use , T-Lymphocytes, Regulatory/drug effects , CD4 Lymphocyte Count , Clonal Anergy/drug effects , Compassionate Use Trials , Dose-Response Relationship, Immunologic , Follow-Up Studies , Humans , Interferon-gamma/blood , Interleukin-17/blood , Interleukin-2 Receptor alpha Subunit/analysis , Multiple Sclerosis, Chronic Progressive/immunology , Multiple Sclerosis, Chronic Progressive/pathology , Myelin Basic Protein/administration & dosage , Myelin Basic Protein/immunology , Peptide Fragments/administration & dosage , Peptide Fragments/immunology , T-Lymphocytes, Regulatory/immunology , Transforming Growth Factor beta/blood , Treatment OutcomeABSTRACT
Structurally well-defined immune stimulatory molecules are important components of new generation molecular vaccines. In this paper, the design and synthesis of two lipid A analogues containing an unnatural tri-lipid acyl group are described. In a totally synthetic liposomal vaccine system, these re-designed lipid A analogues demonstrate potent immune stimulatory properties including antigen specific T-cell activation.
Subject(s)
Lipid A/analogs & derivatives , Lipid A/immunology , Adjuvants, Immunologic/chemical synthesis , Adjuvants, Immunologic/chemistry , Adjuvants, Immunologic/pharmacology , Animals , Drug Design , Lipid A/chemical synthesis , Lipid A/chemistry , Lymphocyte Activation , Mice , Molecular Structure , T-Lymphocytes/immunology , Vaccines/immunologyABSTRACT
MUC1 mucin is a large transmembrane glycoprotein, of which the extracellular domain is formed by a repeating 20 amino acid sequence, GVTSAPDTRPAPGSTAPPAH. In normal breast epithelial cells, the extracellular domain is densely covered with highly branched complex carbohydrate structures. However, in neoplastic breast tissue, the extracellular domain is underglycosylated, resulting in the exposure of a highly immunogenic core peptide epitope (PDTRP in bold above) as well as the normally cryptic core Tn (GalNAc), STn (sialyl alpha2-6 GalNAc), and TF (Gal beta1-3 GalNAc) carbohydrates. In the present study, NMR methods were used to correlate the effects of cryptic glycosylation outside of the PDTRP core epitope region to the recognition and binding of a monoclonal antibody, Mab B27.29, raised against the intact tumor-associated MUC1 mucin. Four peptides were studied: a MUC1 16mer peptide of the sequence Gly1-Val2-Thr3-Ser4-Ala5-Pro6-Asp7-Thr8-Arg9-Pro10-Ala11-Pro12-Gly13-Ser14-Thr15-Ala16, two singly Tn-glycosylated versions of this peptide at either Thr3 or Ser4, and a doubly Tn-glycosylated version at both Thr3 and Ser4. The results of these studies showed that the B27.29 MUC1 B-cell epitope maps to two separate parts of the glycopeptide, the core peptide epitope spanning the PDTRP sequence and a second (carbohydrate) epitope comprised of the Tn moieties attached at Thr3 and Ser4. The implications of these results are discussed within the framework of developing a glycosylated second-generation MUC1 glycopeptide vaccine.
