Latest News

A tale of two colleges
COVID-19 at the University of Wisconsin this fall has been pretty much a non-issue. While we are wearing masks, full in-person teaching is happening on campus. Bars, restaurants, and all other busine…
Read more
Get your Vitamin D to Protect Yourself from COVID-19
This sounds like another hydroxychloroquine or ivermectin hoax, but the science is peer-reviewed. Getting enough vitamin D in your diet is an excellent way to protect yourself from severe COVID-19. E…
Read more
About 35,000 people die from drug-resistant infection in the US. What are we going to do?
When antibiotics first achieved widescale use in the middle of the 20th century, they had a tremendous impact. For example, the mortality rate in England from infectious disease dropped from 25% in 1…
Read more
Nasal nanoSTING vaccines may Provide Lasting Protection Against SARS-CoV-2
All successful vaccines against SARS-CoV-2 have used the spike protein as the target and delivered the vaccine by intramuscular injection, typically a shot in the left or right shoulder. The vaccines…
Read more
Probiotic Bacterium can prevent antibiotic use side effects
Researchers at the University of Maryland School of Medicine demonstrate the power of probiotics. A test group was given Bifidobacterium lactis BB-12 as they took a course of amoxicillin clavula…
Read more

News

Nasal nanoSTING vaccines may Provide Lasting Protection Against SARS-CoV-2


 

All successful vaccines against SARS-CoV-2 have used the spike protein as the target and delivered the vaccine by intramuscular injection, typically a shot in the left or right shoulder. The vaccines have proven to be spectacularly effective, protecting against infection, severe disease, and death. However, recent mutations of SARS-CoV-2 have created varients that can cause breakthrough infections at a significant rate. While those who are vaccinated are still protected against severe disease and death, protection against infection does appear to wane after several months. This can allow the virus to continue to spread and impact those who cannot or will not get vaccinated. SARS-CoV-2 infection begins in the nose and the upper respiratory tract. Intramuscular injection does not stimulate strong mucosal immunity in these areas.

 

An et al. from the University of Texas have developed a single-dose intranasal vaccination system that elicits rapid systemic and mucosal immunity. Importantly, spike-specific IgA responses are present in the nasal compartment and the lung after vaccination and will presumably be better at preventing infection than current vaccines. Inhaled vaccines were difficult to deliver and there was a need for appropriate adjuvants that would stimulate a robust response. (Adjuvants are added to vaccines to enhance the body's immune response to an antigen.)  The authors report the creation of adjuvants that stimulate the STING pathway (STINGa) was the key to vaccine effectiveness.

STINGa was formulated in liposome particles by a simple hydration procedure. These nanoSTING particles were stable at refrigerator temperatures. The active vaccine was created by mixing lyophilized spike proteins with nanoSTING and immediately inoculating mice with the mixture. A convenient, foolproof method of preparing the vaccine will have to be developed for this to have widespread use.

The mice vaccinated with nanoSTING had a rapid immune response in 15 days. The response included neutralizing antibodies, B-cells, T-cells, and serum IgA. Especially important, a strong immune response was found in the nasal immune tissue of the mice, suggesting that they would have strong protection against infection with SARS-CoV-2. Unfortunately, the immunized mice were not challenged by infection since they are not an appropriate model for these types of studies. The authors indicate that studies in hamsters or monkeys where viral challenges are possible is the next set of experiments.

There is a long way to go before this hits clinical trials, but it may eventually be a path toward more robust protection against respiratory viruses.