Why antibodies are important

We know that public health controls are effective. We also know that poverty is the single greatest factor in population health 2. In general this disease has the greatest impact on older males with co-existing illness. It is inevitable that if further antibody studies continue to support the suggestion of a lower infection fatality rate that this will become a component of the political narrative around the evolving debate between ongoing public health controls versus the social, political and economic impact of such controls.

The challenge will be to reboot the economy whilst mitigating the impact of the disease below the threshold at which health systems are able to function. Real-time dashboard. Poverty and social determinants.

Our priority is to help individuals to enhance and optimise their health by providing easy access to a wide range of excellent practitioners and information, supported by management systems and technology that ensure quality of service and value. Our Mission is to provide pre-eminent private healthcare in Hong Kong. We aim to be the best in class fully integrated healthcare service, providing a circle of care for all our patients' needs.

Repulse Bay Family Medicine. Clearwater Bay Family Medicine. Central Specialists Medical Specialists. Home Blog Antibodies: what are they and why are the antibody studies so important? Antibodies: what are they and why are the antibody studies so important? The impact of all infectious illness is ultimately determined by two independent factors: Exposure Risk Individual immune response The goal of the public health controls is to minimise exposure risk. What are antibodies?

Why are antibody tests so difficult or unreliable? What is sensitivity and specificity? What do the early studies show? What information will the antibody studies give us? Individual information It seems reasonable that an individual who has a positive antibody test is likely to have some degree of immunity.

Population information Antibody studies are going to be most effective in giving information in population terms. There are really two main pieces of information that will come out of the population prevalence studies: Population immunity The first is the total number of positive antibody tests.

Infection fatality rate The other information which we will get from population studies is the incidence of unrecognised infections. References 1.

Related articles. When this system recognizes an invader, it goes into action immediately. The cells of this immune system surround and engulf the invader. The invader is killed inside the immune system cells. These cells are called phagocytes. The acquired immune system, with help from the innate system, produces cells antibodies to protect your body from a specific invader.

These antibodies are developed by cells called B lymphocytes after the body has been exposed to the invader. The antibodies stay in your child's body. It can take several days for antibodies to develop.

But after the first exposure, the immune system will recognize the invader and defend against it. The acquired immune system changes throughout your child's life.

We also have another type of immune system known as the innate immune system. The innate immune system is our frontline defense, the first system to respond to a new infection. This includes cells such as neutrophils, macrophages, and dendritic cells. Unlike the adaptive immune system, which includes antigen-specific antibodies that take time to develop, the innate immune system responds to antigens very quickly but in a non-specific way.

Quite often, the innate immune response will take care of an infection before the adaptive immune system even has a chance to start manufacturing antibodies. The adaptive immune system involves more than just B cells, plasma cells, and antibodies—it also includes T cells. T cells are another population of white blood cells that can develop into memory cells, just as B cells can.

They can also differentiate into specialized cells that kill virus-infected cells. The functions of T cells and B cells are different.

B cells develop into plasma cells that produce antibodies T cells do not ; T cells directly kill virus-infected cells B cells do not. Sometimes individuals with a very vigorous T cell immune response will be protected from a pathogen even though they produce low amounts of antibody.

The T cell immune response is much more difficult to measure than the antibody response and is usually only evaluated in specialized research settings. Our adaptive immune response is important because once developed, it is highly specific for the pathogen and provides us with immunologic memory. This serves two purposes. First, it helps build herd immunity. If enough people in a population have immunologic memory, the second wave of infection typically occurs in smaller clusters instead of spreading like wildfire and overwhelming the population and thus our hospitals.

Secondly, our adaptive immune system protects us as we age. Our immunologic memory can last for a very long time. People in their 80s or 90s still maintain immunologic memory to pathogens and vaccines that they were exposed to as children, such as influenza or the measles vaccine. Our capacity to generate immunologic memory is greatest from childhood into late adolescence because the bone marrow, where B cells mature, and the thymus, where T cells mature, are most efficient and productive at younger ages.

As we advance into adulthood, these production systems decline and we gradually lose our ability to generate a vigorous adaptive immune response to new pathogens, particularly in later stages of life. In general, our elderly population has effective immunologic memory to things that they were exposed to when they were younger, but because this is a new virus, elderly people might have a difficult time generating an adaptive antiviral immune response.

This is often compounded by other underlying diseases that weaken the adaptive immune responses. Not exactly. However, when that B cell starts dividing to create clones of itself, the genes in these cloned cells are sprinkled with mutations that produce antibodies that are highly similar but slightly different from the original parent cell. The one that binds best will proliferate the most because it gets activated the most. This process, called affinity maturation , can ratchet up the binding strength of antibodies by more than a thousand-fold.

When an activated B cell starts dividing, many of the progeny cells will have antibodies with similar affinity or less affinity than the original parent cell. But a few will have antibodies with much higher affinity, and the cells that bind best to the target will proliferate.

The result can be thousands of different antibodies that bind to different proteins on a virus or different parts of the same protein. Some of these antibodies might not deter the virus at all, while others may block key proteins, for example the spike protein the coronavirus uses to infect cells. Antibodies that defend cells from infection are called neutralizing antibodies. There are cells in the innate immune system called macrophages, which vacuum up and digest things that are coated with antibodies in a process known as phagocytosis, which literally means cell eating.

Antibodies that block the spike protein can interfere with this binding and neutralize the virus. Antibodies that bind to other SARS-CoV-2 proteins can also help to fight infections by signaling macrophages to engulf and destroy the virus right side. In some people with a viral infection, the antibody response may arise too weakly or too late to fight off the virus.

In other cases, the antibodies made by the immune system may bind tightly to the virus but fail to neutralize it. A vaccine , based on inactivated virus or viral antigens, can prompt your immune system to recognize a virus and produce memory B cells against the virus to guard against a future infection. Vaccines potentially offer long-lasting active immunity , but it may take weeks or months for that protection to develop.

Neutralizing antibodies that target a virus can also be manufactured outside the body and injected into patients or those at high risk of infection to potentially treat or prevent a disease. Therapeutic antibodies can offer rapid protection, but this passive immunity may only last for a few weeks to a month before the injected antibodies are removed by natural processes. The antibodies your body makes are also removed eventually, but your immune system can make more as needed.