ABSTRACT
The immune health of a farm animal can have significant impact on its overall health, welfare and productivity. One of the most vulnerable physiological states for both humans and animals is pregnancy. Many systemic changes correlate with the gravid state, including shifts in the immune system that may impact the ability to respond optimally to pathogen challenge. Because of this, it would be beneficial to be able to monitor the immune health of the pregnant animals closely. Recently, we developed a new nanoparticle-enabled rapid blood test that can detect ongoing immune responses from both laboratory and farm animals. Here, we report that this novel test reveals highly repeatable and acute changes associated with pregnancy and peri-parturition period in laboratory mice and in cattle. We hypothesize that the test score change reflects changes in the immune status of the gravid females related to the humoral immune response. The test is easy to conduct, of low cost, with results obtained in less than 20 min. This rapid test could be potentially used as an onsite test in local farms and small clinics for animal health management.
ABSTRACT
In this study, we investigated the interaction between five biorelevant molecules and citrate-capped gold nanoparticles using dynamic light scattering, ζ-potential analysis, UV-vis absorption spectroscopy, and transmission electron microscopy. The five biomolecules are bovine serum albumin (BSA), two immunoglobulin G (IgG) proteins, immunoglobulin M (IgM), and a polysaccharide molecule, hyaluronan. BSA, IgG, and IgM are high abundance proteins in blood. Hyaluronan is a major component of the extracellular matrix. An abnormal level of hyaluronan in blood is associated with a number of medical conditions including rheumatoid arthritis and malignancy. Five different interaction modes were observed from these molecules. While BSA and IgM interact with the gold nanoparticles by forming electrostatic interactions with the citrate ligands, IgG and hyaluronan adsorb to the nanoparticle metal core by displacing the citrate ligands. BSA, rabbit IgG, and hyaluronan formed a stable monolayer on the nanoparticle surface. Human IgG and IgM caused nanoparticle cluster formation upon interacting with the gold nanoparticles. For the first time, we discovered that hyaluronan, a highly negatively charged polyglycosaminoglycan, exhibits an exceptionally strong affinity toward the citrate-gold nanoparticles. It can effectively compete with IgG to adsorb to the gold nanoparticles. This finding has exciting implications for future research: the molecular composition of a protein corona formed on a nanoparticle surface upon mixing the nanoparticle with blood or other biological fluids may vary according to the pathological conditions of individuals, and the analysis of these compositions could potentially lead to new biomarker discovery with diagnostic applications.