Persistence of Hemoglobin Allergenicity and Antigenicity during Metamorphosis of Chironomidae (Insecta: Diptera)

Abstract. Chironomid hemoglobins are potent allergens. The allergenic and antigenic activities of these hemoglobins are studied with the help of RAST, RAST inhibition and double immunodiffusion. Human as well as rabbit antisera were used. It was shown that hemoglobins are the main antigenic/allergenic compo nents in extracts of Camptochironomus tentans larvae. Furthermore, immunological cross-reactivity among larvae, pupae and adult midges of this species are shown to be due to [he existence of hemoglobin antigenic de terminants in all developmental stages of this insect

Functional material features of Bombyx mori silk light versus heavy chain proteins

Bombyx mori (BM) silk fibroin is composed of two different subunits; heavy chain and light chain fibroin linked by a covalent disulphide bond. Current methods of separating the two silk fractions is complicated and produces inadequate quantities of the isolated components for the study of the individual light and heavy chain silks with respect to new materials. We report a simple method of separating silk fractions using formic acid. The formic acid treatment partially releases predominately the light chain fragment (soluble fraction) and then the soluble fraction and insoluble fractions can be converted into new materials. The regenerated original (total) silk fibroin and the separated fractions (soluble vs. insoluble) had different molecular weights and showed distinctive pH stabilities against aggregation/precipitation based on particle charging. All silk fractions could be electrospun to give fibre mats with viscosity of the regenerated fractions being the controlling factor for successful electrospinning. The silk fractions could be mixed to give blends with different proportions of the two fractions to modify the diameter and uniformity of the electrospun fibres formed. The soluble fraction containing the light chain was able to modify the viscosity by thinning the insoluble fraction containing heavy chain fragments, perhaps analogous to its role in natural fibre formation where the light chain provides increased mobility and the heavy chain producing shear thickening effects. The simplicity of this new separation method should enable access to these different silk protein fractions and accelerate the identification of methods, modifications and potential applications of these materials in biomedical and industrial applications

Studies on Antigens Useful for Detection of IgE Antibodies in Isocyanate-Sensitized Workers

Peer Reviewe