Suzanna J. Horvath

Restricted use of T cell receptor V genes in murine autoimmune encephalomyelitis raises possibilities for antibody therapy

Experimental allergic encephalomyelitis (EAE) is a paralytic autoimmune disease induced in susceptible animals by active immunization with myelin basic protein (MBP) or by passive transfer of MBP-specific T helper (TH) lymphocytes. We have analyzed the T cell receptor genes of 33 clonally distinct TH cells specific for a nonapeptide of MBP inducing EAE in B10.PL (H-2u) mice. All 33 TH cells used two alpha variable gene segments (V alpha 2.3, 61%; V alpha 4.2, 39%), the same alpha joining gene segment (J alpha 39), and two V beta and J beta gene segments (V beta 8.2-J beta 2.6, 79%; V beta 13-J beta 2.2, 21%). The anti-V beta 8 monoclonal antibody F23.1 was found to block completely recognition of the nonapeptide by V beta 8 TH cells in vitro and to reduce significantly the susceptibility of B10.PL mice to peptide-induced EAE.

Characterization of cloned cDNA representing rat myelin basic protein: Absence of expression in brain of shiverer mutant mice

A cDNA library was constructed from mRNA isolated from the brains of 18-day-old rats, the age at which myelin biosynthesis is maximal. A synthetic DNA probe synthesized based on reverse translation of the amino acid sequence of rat myelin basic protein (MBP) was used to select two cDNA clones encoding MBP. A 1.5 kb Eco RI fragment from one clone was completely sequenced. When translated, a portion of this sequence was identical at 126 of 127 positions with the reported amino acid sequence for small MBP from the rat. Brains from mice of the homozygous shiverer genotype contained neatly reduced amounts of MBP mRNA relative to wild type. A deletion of MBP sequences in the genome of shiverer mice was also demonstrated. cDNAs for MBP will allow molecular investigation of the role this gene plays in both dysmyelinating and demyelinating diseases, as well as questions of MBP biosynthesis.

The myelin proteins of the shark brain are similar to the myelin proteins of the mammalian peripheral nervous system

SummaryThe two major structural proteins in the shark CNS are similar to the structural proteins, Po and myelin basic protein (MBP), found in the mammalian peripheral nervous system (PNS). Shark Po is 46% similar to its mammalian counterpart. The extracellular domain of shark Po also appears to be organized as an immunoglobulin-like domain that mediates homotypic interactions. The intracellular domain of shark Po also is very basic and may play a role in myelin condensation analogous to that of MBP. Shark MBP is 44% similar to mammalian MBP. Both MBPs show conserved interspersed regions and are present in multiple forms that arise by alternative splicing of a single transcript. These structural analyses indicate that the complexities seen in mammalian myelin arose early during vertebrate evolution.

Autoimmune T cells: Immune recognition of normal and variant peptide epitopes and peptide-based therapy

Experimental autoimmune encephalomyelitis (EAE) results from T helper (TH) cell recognition of myelin basic protein (MBP). We have characterized TH cell reactivity in B10.PL and PL/J (H-2u) mice to 39 N-terminal MBP peptide derivatives of different lengths and with individual amino acid substitutions. The peptide determinant of murine MBP can be divided into a minimal stimulatory core region (residues 1-6) and a tail region (residues 7-20) that alters the structure of the core region to affect both T cell recognition and MHC binding. Core recognition by B10.PL and PL/J mice is highly similar but in one case strain dependent. Peptide analogs that do not stimulate MBP-specific TH cells but bind to the I-Au molecule competitively inhibit T cell reactivity to MBP in vitro and prevent the induction of EAE in vivo.

An automated DNA synthesizer employing deoxynucleoside 3'-phosphoramidites.

Publisher Summary This chapter describes the design of an automated deoxyribo nucleic acid (DNA) synthesizer that can synthesize longer strands of DNA at lower cost. Moreover, two, three, or four bases can be incorporated at appropriate positions in accordance with the ambiguity of the genetic code for individual amino acid residues. The design and operation of such a synthesizer is described in this chapter. The primary reactor is a flow through column, and the reagent and solvent deliveries are controlled by a series of zero-dead volume, pneumatically actuated diaphragm valves. To move reagents and solvents from the reservoirs, positive argon pressure is used rather than a mechanical pump. This chapter has carried out extensive studies, concerning the synthesis of DNA mixtures. This chapter discusses the using color-coded 5’ protecting groups on each of the four bases and computer analysis for multiple absorption spectrum analysis. This chapter discusses the ability to prove the equimolar existence of all desired sequences in the final mixture.