Detection of chromogranin A in the adrenal gland extracts of different animal species by an enzyme-linked immunosorbent assay using Thomsen–Friedenreich antigen-specific Amaranthus caudatus lectin

Development of enzyme immunoassay for chromogranin A (CgA) and profiling of plasma CgA concentrations in the cow

The objectives of this study were to establish and characterize a homologous immunoassay for bovine chromogranin A (bCgA) and to profile plasma bCgA concentrations during early pregnancies. We synthesized oligopeptide corresponding to the amino acid sequence 341-355 of bCgA for immunizing rabbits and peptide corresponding to the amino acid sequence 336-365 of bCgA for both a biotinylated tracer and reference standards. Recombinant bCgA protein was also generated in Escherichia coli lysate. Dose-dependent displacement curves were obtained from 1 to 1,000 nM of the reference standards. The displacement curves showed a good relationship between the reference standards of the synthetic peptide and the serially diluted plasma sample or recombinant bCgA protein generated in the present study. The assay sensitivity defined as the value of two standard deviations below the zero standard was calculated as 0.46 nM. The intraassay and interassay coefficients of variation were 6.48% and 13.4%, respectively. Changes in the plasma bCgA concentrations in early pregnancies undulated in nonpregnant animals. The results of the present study suggest that assaying plasma bCgA concentrations could be utilized as measures to evaluate the physiological status of cattle.

Chromogranins can be measured in samples from cats and dogs

BACKGROUND

Methods for objective evaluation of stress in animals are important, but clinically difficult. An alternative method to study the sympathetic activity may be to investigate Chromogranin A (CGA), Chromogranin B (CGB) and Secretogranin II (SG2). The aim of this study was to investigate the cross-reactivity of CGA, CGB and SG2 between man, cat and dog and to explore possibilities to measure these proteins in samples from cats and dogs.

RESULTS

Adrenal gland extracts from feline and canine species were measured by region-specific radioimmunoassays in different dilution steps to explore possible inter species cross reactivity. High cross reactivity was found for cats in the CGA17-38, CGA324-337, CGA361-372, CGB and SG2 assays. High cross reactivity was found for dogs in the CGA17-38, CGA361-372, CGB and SN assays. The method measuring the intact CGA was not useful for measurements in cats and dogs.

CONCLUSIONS

Region-specific assays measuring defined parts of CGA, CGB and SG2 can be used for measurements in samples from cats and dogs. These results are promising and will allow for further studies of these proteins as possible clinical biomarkers in cats and dogs.

Comprehensive list of lectins: origins, natures, and carbohydrate specificities

More than 100 years have passed since the first lectin ricin was discovered. Since then, a wide variety of lectins (lect means "select" in Latin) have been isolated from plants, animals, fungi, bacteria, as well as viruses, and their structures and properties have been characterized. At present, as many as 48 protein scaffolds have been identified as functional lectins from the viewpoint of three-dimensional structures as described in this chapter. In this chapter, representative 53 lectins are selected, and their major properties that include hemagglutinating activity, mitogen activity, blood group specificity, molecular weight, metal requirement, and sugar specificities are summarized as a comprehensive table. The list will provide a practically useful, comprehensive list for not only experienced lectin users but also many other non-expert researchers, who are not familiar to lectins and, therefore, have no access to advanced lectin biotechnologies described in other chapters.