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Biomedical subjects

G R Wallace

Publications and source records attributed to G R Wallace.

6 recordsLinked to original sources
PubMed1992

Mapping of a visceral leishmaniasis-specific immunodominant B-cell epitope of Leishmania donovani Hsp70.

We have shown that a member of the 70-kDa heat shock protein (Hsp70) family is a major target of the humoral immune response during Leishmania donovani infection. A recombinant fusion protein was recognized by sera from 92% (35 of 38) of patients with visceral leishmaniasis, including representatives from each of the major regions where it is endemic. Serological analysis of recombinant Hsp70, expressed by a series of deletion constructs, identified the carboxy-terminal region as the immunodominant site. This region, which is the most evolutionarily divergent part of the molecule, was recognized by all sera from patients with visceral leishmaniasis which exhibited an anti-Hsp70 response. Purified recombinant L. donovani Hsp70 was not recognized by sera from patients with cutaneous leishmaniasis, Chagas' disease, leprosy, malaria, or schistosomiasis. To determine the regions involved in antibody recognition, a series of overlapping peptides were synthesized on polyethylene pins by the Pepscan method, and a hexamer, EADDRA, was identified by the visceral leishmaniasis serum samples as an immunodominant B-cell epitope.

Amino Acid Sequence↗
PubMed1991

Cloning of microbial epitopes relevant for T- and B-cells.

This review summarises, and illustrates, the technology that is available for the molecular cloning and precise identification of T-cell and B-cell epitopes, particularly those of bacteria and parasites. Methods include: selective cloning following subtractive hybridization of nucleic acids; selective screening of expression libraries; analysis of subcloned "epitope libraries" or "deletion constructs"; scanning of multiple synthetic peptides, and computer enhanced prediction. The direct sequencing of polymerase chain reaction products allows the rapid analysis of epitope heterogeneity occurring among natural populations. Multiple epitopes can be assembled either by synthesis or by the expression of polymeric epitope-bearing peptides. Prospects for probing expression libraries with T-cells are bleak due to the complexities of antigen processing, presentation and T-cell recognition in vitro. Elucidation of the enzymic steps involved in processing, resolution of peptide/MHC II co-crystals, and pairing of a large number of known epitopes with their functional restriction elements will significantly improve the ability to predict T-cell epitopes.

Animals↗
PubMed1979

Nonfamilial anterior corneal dystrophy.

A 31-year-old woman with subepithelial corneal opacification and numerous clear round or oval areas of epithelial edema confined to the palpebral fissure underwent a penetrating keratoplasty. The clinical appearance was similar to that of a severe Meesmann or Stocker-Holt dystrophy. The prominent histopathologic features were thickening and excrescences of the epithelial basement membrane, intense basal cell edema, but no intraepithelial cysts. The basement membrane changes are compatible with those seen in Meesmann, Stocker-Holt, and map-dot-fingerprint dystrophy, but the lack of intraepithelial cysts is not characteristic of these dystrophies. This case represents a variant of the known anterior corneal dystrophies which have an overproduction of epithelial basement membrane.

Adult↗
PubMed1978

Effective teaching.

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Educational Measurement↗