Question

1. Place the following in the correct order from initiation to end of inflammation (some events may happen simultaneously)

Attraction of phagocytes

Clot formation around area

Damage/injury

Histamine released

Mast cell activated

Neutrophils enter tissue

Phagocytes attack

Remove debris

Swelling

Tissue repair

Vasodilation

2. Explain humoral immunity; and the active, passive, natural and acquired componenents.

Answer 1

Question 1. Place the following in the correct order from initiation to end of inflammation (some events may happen simultaneously)

Answer:

1. Damage/injury

2. Swelling

3. Clot formation around area

4. Vasodilation

5. Mast cell activated

6. Histamine released

7. Attraction of phagocytes

8. Neutrophils enter tissue

9. Phagocytes attack

10.Remove debris

11. Tissue repair

Queston 2. Explain humoral immunity; and the active, passive, natural and acquired componenents.

Answer: Humoral immunity is defined as the production of specific antibodies against infectious pathogens. Antibodies act through three main ways:

(a) neutralization, binding to free or cell-associated antigens and thereby preventing cell entry and/or biological activity of a pathogen;

(b) opsonization, coating the surface of the pathogen to facilitate phagocytosis; and (c) complement activation, helping antibodies and phagocytic cells to clear pathogens by inducing an inflammatory response.

It is the aspect of immunity that is mediated by macromolecules found in extracellular fluids such as secreted antibodies, complement proteins, and certain antimicrobial peptides. Humoral immunity is so named because it involves substances found in the humors, or body fluids. Initiation of the humoral immune response requires activation of B cells by antigens and interaction with a specific subset of CD4+ T cells denoted as follicular helper T cells in lymph nodes. This interaction induces differentiation of B cells into long-lived plasma cells, which secrete new antibodies, and into memory B cells that enter the circulation and rapidly differentiate into plasma cells upon antigen re-exposure.

Active immunity

Active immunity is the development of antibodies in response to stimulation by an antigen. Active immunity is explained as "results when exposure to a disease organism triggers the immune system to produce antibodies to that disease," and can happen one of two ways: Through infection with the actual disease, which is known as natural immunity; or through a vaccination (essentially, a killed or weakened form of the disease that won't make someone ill, but will trigger the body to make antibodies), which is known as vaccine-induced immunity.

Active immunity that results from either situation—natural immunity or vaccine-induced immunity—will allow a person's immune system to recognize the specific disease, if they ever come into contact with it again, which will then trigger the body to produce the antibodies needed to fight it off.

Active immunity is often longer-lasting and may sometimes even provide life-long protection—but that's entirely based on the disease itself. Immunity to the varicella virus (aka, chickenpox)—either via acquiring the infection as a child or through a vaccine—can provide lifelong immunity or long-lasting protection for up to 10 to 20 years. Whereas a yearly flu shot must be repeated annually, as it provides the most protection within the first three months, and begins to lose most effectiveness after six months. It's also important to note that active immunity isn't immediate—it can sometimes take several weeks to develop.

Passive immunity

Passive immunity refers to the process of providing IgG antibodies to protect against infection; it gives immediate, but short-lived protection—several weeks to 3 or 4 months at most. Passive immunity is usually classified as natural or acquired. The transfer of maternal tetanus antibody (mainly IgG) across the placenta provides natural passive immunity for the newborn baby for several weeks/months until such antibody is degraded and lost. In contrast, acquired passive immunity refers to the process of obtaining serum from immune individuals, pooling this, concentrating the immunoglobulin fraction and then injecting it to protect a susceptible person.

The four most commonly used immunoglobulin preparations are as follows.

1. Human Hepatitis B Immunoglobulin Ph.Eur.* Bio Products Laboratory: Human hepatitis B immunoglobulin is presented as two vial sizes of 200 and 500 IU. Each millilitre contains 10–100 mg/ml human protein of which at least 95% are gammaglobulins (IgG). This product is prepared from plasma from screened donors, selected from the USA. One millilitre contains not (i) <100 IU of hepatitis B antibody. Its use occupationally is for the immediate protection of non-immune health care workers exposed to hepatitis B viruses (together with an appropriate vaccination programme).

2. Human Rabies Immunoglobulin Ph.Eur.* Bio Products Laboratory: Human rabies immunoglobulin is presented as a vial size of 500 IU. Each millilitre contains 40–180 mg/ml human protein of which at least 95% are gammaglobulins (IgG). This product is prepared from plasma from screened donors, selected from the USA. One millilitre contains not (ii) <150 IU of rabies antibody. It is given as part of post-exposure prophylaxis to non-immune individuals with a rabies prone exposure.

3. Human Tetanus Immunoglobulin Ph.Eur.* Bio Products Laboratory: Human tetanus immunoglobulin is presented as a vial size of 250 IU. Each millilitre contains 40–180 mg/ml human protein of which at least 95% are gammaglobulins (IgG). This product is prepared from plasma from screened donors, selected from the USA. One millilitre contains not (iii) <100 IU of tetanus antibody. It is unlikely that this preparation would be used for health care workers; it is given both as part of the management of tetanus prone wounds where there is heavy soil/manure contamination and as part of the management of all wounds if the individual is thought to be non-immune.

4. Human Varicella-Zoster Immunoglobulin Ph.Eur.* Bio Products Laboratory: Each vial contains 250 mg protein (40–180 mg/ml) of which at least 95% are gammaglobulins (IgG). This product is prepared from plasma from screened donors, selected from the USA. One millilitre contains not (iv) <100 IU of Varicella-Zoster antibody. It is given as part of post-exposure prophylaxis to specified non-immune individuals exposed to chickenpox.