Saar Kuzi
Alessandra Coutinho Fernandes
William Cope
Richard Tapping
Kashif Ahmad
Reda Sadki
Shubhra Kanti Karmaker Santu
Adam P Rusch
Elizabeth Edwards
Matthew LawFA16 Immunization Module’s Updates
Active versus passive immunity
Active immunity relies on the full capacity of one’s own immune system to provide protection against specific antigens. Examples of antigens that are typically protected against by one’s active immunity include hepatitis B surface antigen, polio, rabies (4). Active immunity works through exposure to an antigen that causes disease, overcoming the disease, and the formation of memory B cells that will return to the bone marrow and survey throughout the circulatory system for re-exposure (4).
Passive immunity relies on boosting a person’s innate immune system through the introduction of externally produced adaptive immune system products. These products include different kinds of immunoglobins such as IgG in utero and IgA from a mother’s breast milk which provide an infant with a passive immunity for up to a year. Other external sources of immunoglobins that can be used in passive immunity include “homologous pooled human antibody, homologous human hyperimmune globulin, and heterologous hyperimmune serum (4).”
Homologous pooled human antibody is defined as the combination of IgG fractions from many donors which will confer protection against different antigens (4). It is primarily used to prevent disease after exposure to hepatitis A and measles. It is also used as treatment for patients with congenital immunoglobulin deficiencies (4). Homologous human hyperimmune globulin refers to a more selective method of collecting antibodies (4). The product of this pool of antibodies is highly specific against one antigen and is primarily used to protect against diseases such as hepatitis B, rabies, tetanus, and varicella (4). The final major source of passive immunity antibodies is heterologous hyperimmune serum which also called anti-toxin (4). The heterologous term refers to the product being produced by a different animal, in most cases it is pooled from horses—which can cause “serum sickness” in some patients (4). The product is typically specific against one antigen and is primarily used to treat botulism and diphtheria (4).
All charts and references are from the PDF “Principles of Vaccination” which can be found in Update 1 of FA16 Immunization Module.
4 "Principles of Vaccination." Centers for Disease Control and Prevention.
Centers for Disease Control and Prevention, 08 Sept. 2015. Web. 27 Sept. 2016.
@Omar, I found your post very interesting! The ability of antibodies from one individual to protect another from disease is fascinating. I was unaware of the varying sources of passive immunity and how they are used to treat different diseases. One question that I do have is can passive immunity aid in the establishment of an active immunity, especially in infants who do not have the established memory cells that adults have?
Future Dr. Calderon, your post acted not only as a terrific review over active and passive immunity, but also as a means to acquire more knowledge on the topic of passive immunity. I truly find it marveling that a mother's antibodies provides the means for shared protection. Would you or any of my colleagues happen to know if the infant has any vulnerable periods of immunological development during this period of 'borrowed immunity'?
Wow, I didn't realize the maternal antibodies were able to protect the neonate for as long as a year. That's some great passive immunity! Does anyone know why the colostrum is so full of antibodies and why the mother stops producing it even though she continues producing breast milk?