Monoclonal Antibodies

General procedure to generate monoclonal antibodies

One of the most important innovations in Immunology during the second half of the 20th century was the development of monoclonal antibodies, by Georges Kohler and Cesar Milstein. Kohler and Milstein were awarded the Nobel Prize in Physiology or Medicine in 1984, which they shared with Niels K. Jerne for discoveries about the control and specificity of the immune system.

I first learned of the work of Kohler and Milstein as an undergraduate. In 1986, the process of making monoclonal antibodies was still very new and cutting edge, but as with most stories in science, the hybridoma process did not originate so suddenly or cleanly. Studies of leukemic cell lines in the late 1960’s and early 1970’s  indicated that a B-cell produced only one kind of an antibody molecule, but there was no way to alter the kind of antibody made by an existing B-cell. The leukemia cell lines did offer the clue to the method for developing a cell line which could make a monoclonal antibody recognizing a specific, desired antigen. As we learned in lecture, antibody-producing (plasma) B cells have a limited lifespan in the circulation; it is the memory B-cells that have an extended lifespan, but they do not produce antibody until stimulated by antigen and differentiate back into plasma cells.

Kohler and Milstein’s innovation was this:  a mouse is immunized with an antigen, so that B-cells present in the mouse would be stimulated to produce antibody capable of recognizing that antigen. Once antibody production is verified by measurement of serum antibody levels, the mouse is sacrificed, and it’s B-cells are isolated. These B-cells would normally only last for a limited period of time before they begin to die. Kohler and Milstein fused these normal B-cells from the immunized mouse with an immortal cancerous cell line, which had lost the ability to make antibody. Cells which have not fused with a cancerous partner are killed by administration of a drug, and the only surviving cells are B-cells which have fused with the cancer cell.

The B-cell/cancer cells fusions (called hybridomas) are diluted and dispensed into growth chambers, so that only one hybridoma is present in each chamber. Consequently, only one antibody is produced in each growth chamber. The scientist laboriously examines each chamber for chambers that are positive for an antibody of interest, by adding the antigen of interest. Once that has been accomplished, the positive “clone” can be grown essentially indefinitely, and the antibody harvested in massive amounts.

I alluded to a bit of back story up above. In 1973, two years before Kohler and Milstein’s seminal publication, Schwaber and Cohen at the University of Chicago published the fusion of a mouse cell line with human non-antibody producing cells, resulting in a hybrid cell capable of making human antibody. Some historians of science have suggested that significantly more credit should have been given to the first two scientists, however the innovation brought in by Kohler and Milstein (the ability to make an immortalized cell line secreting a single antibody of desired specificity,) while utilizing the basic principle of Schwaber and Cohen, extended and adapted that work in a new direction. And this is the way science works!

BONUS: Describe the use of a monoclonal antibody from a clinical setting. There’s a million of them!

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About ycpmicro

My name is David Singleton, and I am an Associate Professor of Microbiology at York College of Pennsylvania. My main course is BIO230, a course taken by allied-health students at YCP. Views on this site are my own.

Posted on March 30, 2011, in A bit 'o history, Bonus!, Lecture. Bookmark the permalink. 12 Comments.

  1. They are use in diagnostic test for example the Western blot test and immuno dot blot tests detect the protein on a membrane, also they are very useful in immunohistochemistry which detect antigen in fixed tissue sections.

  2. Mylotarg (Gemtuzumab) is used to help with Acute Myelogenous Leukemia. This particular antibody interferes with a specific protein and can help stop cancer cell growth.

    • This is an example of one of the therapeutics that comes closest to Paul Ehrlich’s “Magic Bullet.” Essentially all forms of cancer therapy (surgical resection of tumor, radiation therapy, chemotherapy) can treat the tumor, but are incredibly hard on the body, and convey a significant amount of ancillary damage. This antibody specifically hones in on an antigen on the cancer cells, and delivers a toxic compound to those cells while minimizing the damage to health cells around them.

  3. Brittany MacFadden

    Since monoclonal antibodies specifically bind to target cells. This monoclonal antibody therapy may then stimulate the patient’s immune system to attack those cells. There are so many uses for a monoclonal antibody like autoimmune diseases by using the monoclonal antibody infliximab and adalimumab, which are effective in rheumatoid arthritis, Crohn’s disease and ulcerative Colitis because they are able to bind to and inhibit TNF-α…(a receptor)
    There’s a whole list I found of different monoclonal antibodies and it was interesting to look at how many different diseases they target.

  4. They can be used to detect minute amounts of hormones. This is why they are used in pregnancy tests. These monoclonol antibodies test specifically for human chorionic gonadotropin (HCG).

  5. I just found another one! The antigen OKT3 is used to bind to the T3 cells to alleviate organ regection.

  6. Another example i found was
    Infliximab (Remicade®) and adalimumab (Humira®).These two Bind to tumor necrosis factor-alpha (TNF-α). They show a promise against some inflammatory diseases such as rheumatoid arthritis (by blunting the activity of Th1 cells).
    Some potential side-effects can convert a latent case of tuberculosis into active disease and can induce the formation of autoantibodies (by promoting the development of Th2 cells).

  7. Brittany MacFadden

    Here’s two more that deal with killing or inhibiting malignant cells:
    1. Rituximab (trade name = Rituxan®). Binds to the CD20 molecule found on most B-cells and is used to treat B-cell lymphomas.
    2. Zevalin®. This is a monoclonal antibody against the CD20 molecule on B cells (and lymphomas) conjugated to either
    —the radioactive isotope indium-111 (111In) or
    —the radioactive isotope yttrium-90 (90Y)

  8. There are a lot of these and here are some more!!
    1.) basiliximab[22] Acute rejection of kidney transplants
    inhibits IL-2 on activated T cells chimeric
    2.) daclizumab[22] Acute rejection of kidney transplants
    inhibits IL-2 on activated T cells

  9. For an insight into the complications in the initial making of monoclonal antibodies you might like to see the online exhibition: ‘A healthtech revolution in the making: The story of Milstein and the making of monoclonal antibodies’ at http://www.whatibiotechnology.org

    • Thanks for the link! I do not get the opportunity most semesters to cover the tools of immunology in this introductory microbiology class. I had a bit of extra time in the Spring of 2011 when this posting went up and did cover monoclonals, Western blots, and ELISAs in very superficial detail.

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