Over the past two decades, the use of nanoparticles in medicine has steadily increased. However, their safety and effect on the human immune system remains an important question.
B lymphocytes are responsible for the production of antibodies, are central to the vaccine response, are an important part of the body’s immune system, and are central to research in other areas such as oncology and autoimmune diseases. B lymphocytes are therefore attractive targets for the development of prophylactic and therapeutic vaccines.
Gold, which has good body tolerance and easy ductility, has the particularity of absorbing light and then releasing heat, and its special physical and chemical properties can be used in cancer research, so it becomes an excellent candidate for nanomedicine.
Researchers from the University of Fribourg in Switzerland recently published a paper in the journal ACS Nano entitled: Polymer-Coated Gold Nanospheres Do Not Impair the Innate Immune Function of Human B Lymphocytes in Vitro.
The researchers made gold nanoparticles with a diameter of 15 nanometers, and experimental results showed that the gold nanoparticles can target tumors, and when exposed to a light source, the gold nanoparticles release heat and destroy neighboring cancer cells. Drugs can also be attached to the surface of a nanoparticle and then delivered to a specific location. Further research showed that the polymer-coated spherical gold nanoparticles could boost the immune system.
To test the safety of gold nanoparticles and the best medical formulation, the researchers created spherical gold nanoparticles with a polymer coating, spherical gold nanoparticles without a polymer coating, and rod-shaped gold nanoparticles to explore the effects of coating and shape. Human B lymphocytes were then exposed to these different gold nanoparticles for 24 hours to check the activation of the immune response.
By tracking activation markers expressed on the surface of B lymphocytes, it was possible to determine the extent to which gold nanoparticles activated or suppressed the immune response. None of the various nanoparticles tested showed adverse effects, but their effects on the immune response varied depending on their shape and the presence of a polymer coating on the surface. To be specific:
1. Uncoated gold nanoparticles tend to clump together, making them unsuitable for biomedical use;
2. Spherical gold nanoparticles coated with protective polymers can stabilize and do not damage B-lymphocyte function;
3. Rod-like gold nanoparticles can inhibit the immune response, possibly because rod-like gold nanoparticles are too heavy and have an impact on cell membranes.
The targeting of gold nanoparticles allows the use of lower doses of immune stimulants while maintaining an effective immune response. If the nanoparticles are harmless to all immune cells, they can also improve efficacy while reducing side effects. Then more targeted and better tolerated treatments can be developed, especially in the field of oncology.
B lymphocytes are at the heart of vaccine responses, as well as in other fields such as oncology and autoimmune diseases. The study shows that gold nanoparticles can deliver existing drugs directly to B lymphocytes to reduce the necessary dose and potential side effects. And, because of gold’s excellent malleability, gold nanoparticles can be made small enough to cross the blood-brain barrier and be delivered directly to brain cancer cells with specific anti-tumor drugs for the treatment of brain tumors.
Gold nanoparticles, which can act as protective carriers for vaccines or other drugs, can be easily delivered to B lymphocytes, and this study establishes a way to evaluate the safety of nanoparticles on B lymphocytes, something that has never been done before. This approach is particularly useful for future research, as clear guidelines are still needed for the use of nanoparticles in medicine.
