Dublin: When microorganisms such as bacteria or viruses infect us, our immune system kicks in. It is highly trained to understand, eliminate infections and remove any damages caused by them.
What is the importance of body clock?
Although it is generally believed that our immune system functions in the same way all the time, whether during the day or at night, but research going on for more than half a century shows that our body The immune system actually responds differently during day and night. The reason for this is our body’s natural clock or body clock. Every cell in the body, including our immune cells, can tell what time of day it is.
Body clock evolved over millions of years
Our body clock has evolved over millions of years to help us survive. Each cell of the body contains a collection of proteins that indicate the time based on their levels. Knowing whether it is day or night means that our body can adjust its actions and behaviors (such as when we want to eat) at the right time.
Fatiguing chemical is made in the body at night
Our body clock does this by generating a 24-hour rhythm (also called circadian rhythm) in the way cells function. For example, our body clock ensures that we only produce melatonin at night, as this chemical makes us tired. It signals that it is time to sleep.
Immune cells do this special job
Our immune system is made up of many different types of immune cells that constantly patrol the body in search of evidence of infection or damage, but it is our body clock that determines whether they Where are the cells located at particular times of the day?
Broadly speaking, our immune cells move into tissues during the day and then spread throughout the body at night. This circadian rhythm of immune cells may have evolved so that at times when we are most likely to be infected, immune cells are located directly in tissues to attack.
Our immune cells move around in the body at night and stop at our lymph nodes. Here they form a memory of what happened during the day, including any transitions. This ensures that they can respond better the next time they face an infection.
How is it decided how sick we will be?
Given the body clock’s control over our immune system, it is hardly surprising to learn that some research has shown that the timing of our exposure to a virus, such as influenza or hepatitis, can determine whether we How sick will he be? The exact timing may vary depending on the virus associated.
Benefits of taking cholesterol-lowering medicine before bedtime
Other research has also shown that the time of administration of medicines determines their effect, but here also it depends on the drug concerned. For example, since we make cholesterol while we sleep, taking cholesterol-lowering medication just before bedtime seems to provide the most benefit. It has also been shown that the time of day affects the functioning of certain types of immune cells.
body clock and vaccine
There is also enough evidence to suggest that the vaccines that create an immune ‘memory’ against the virus of a particular disease are influenced by our body clock and the time of day when a vaccine is administered. is.
For example, in 2016 a trial of more than 250 adults aged 65 years and older showed that those who were vaccinated for influenza in the morning (between 9 a.m. and 11 a.m.) had less exposure to the vaccine in the afternoon (between 9 a.m. and 11 p.m.). Between 3 pm and 5 pm), there was a higher antibody response than those who got it.
More recently, people around the age of 25 who were immunized with the BCG (tuberculosis) vaccine between 8 and 9 a.m. had higher immunity than those who were vaccinated between 12 and 1 p.m. There was a reaction. So for some vaccines, there is evidence that the morning vaccination may provide a stronger response.
One reason we show better immune responses to vaccines in the morning may be that our body clock regulates our sleep. In fact, studies have shown that getting enough sleep after hepatitis A vaccination increases the number of specific immune cells associated with the vaccine, which improves the immune response.
It is still not fully understood why sleep improves response to vaccines, but it may be because our body clock directly controls immune cell function and location during sleep. does. So, for example when we are sleeping it sends immune cells to our lymph nodes to know which infections were encountered during the day, and to create a ‘memory’ of it.
This of course raises the question of how all this can be related to the current pandemic and vaccination programs around the world. How our immune body clock works may be important in case we develop COVID-19. Interestingly, the receptor that allows the COVID virus, SARS-CoV-2, to enter our cells is controlled by our body clock.
This could mean that we are more likely to have COVID-19 at certain times of the day, but more research will be needed to determine that.
However, the question is yet to be answered whether the specific time at which we get the Kovid-19 vaccine affects our immune system against the disease.
Given the high effectiveness of many COVID-19 vaccines (Pfizer and Moderna are both reported to be over 90% effective) and the urgency with which we need to vaccinate, people should be vaccinated at any time of day.
But current and future vaccines that do not have such high efficacy rates, such as the flu vaccine or if they are used in people with poor immune responses (such as the elderly), may lead to a more accurate ‘time-bound’ approach. Resistance can be ensured.