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Producing monoclonal antibodies

Some types of assays require better antibody specificity and affinity than can be obtained using a polyclonal antiserum. To attain this high specificity, all of the antibodies must bind with high affinity to a single epitope. This high specificity can be provided by monoclonal antibodies (mAbs) . [link] compares some of the important characteristics of monoclonal and polyclonal antibodies.

Unlike polyclonal antibodies, which are produced in live animals, monoclonal antibodies are produced in vitro using tissue-culture techniques. mAbs are produced by immunizing an animal, often a mouse, multiple times with a specific antigen. B cells from the spleen of the immunized animal are then removed. Since normal B cells are unable to proliferate forever, they are fused with immortal, cancerous B cells called myeloma cells, to yield hybridoma cells. All of the cells are then placed in a selective medium that allows only the hybridomas to grow; unfused myeloma cells cannot grow, and any unfused B cells die off. The hybridomas, which are capable of growing continuously in culture while producing antibodies, are then screened for the desired mAb. Those producing the desired mAb are grown in tissue culture; the culture medium is harvested periodically and mAbs are purified from the medium. This is a very expensive and time-consuming process. It may take weeks of culturing and many liters of media to provide enough mAbs for an experiment or to treat a single patient. mAbs are expensive ( [link] ).

Diagram showing production of monoclonal antibodies. Antigen is injected into an animal (such as a mouse) Spleen cells are extracted. Myeloma line cells from a cell culture are added to the spleen cells in a test tube. Then, hybrid cells are selected and grown. Hybrid cells are separated and allowed to proliferate into clones (hybridomas). Each hybrid produces a different antibody and the desired antibody is selected. This hybridoma is then grown to produce large batches of desired mAB.
Monoclonal antibodies (mAbs) are produced by introducing an antigen to a mouse and then fusing polyclonal B cells from the mouse’s spleen to myeloma cells. The resulting hybridoma cells are cultured and continue to produce antibodies to the antigen. Hybridomas producing the desired mAb are then grown in large numbers on a selective medium that is periodically harvested to obtain the desired mAbs.
Characteristics of Polyclonal and Monoclonal Antibodies
Monoclonal Antibodies Polyclonal Antibodies
Expensive production Inexpensive production
Long production time Rapid production
Large quantities of specific antibodies Large quantities of nonspecific antibodies
Recognize a single epitope on an antigen Recognize multiple epitopes on an antigen
Production is continuous and uniform once the hybridoma is made Different batches vary in composition

Clinical uses of monoclonal antibodies

Since the most common methods for producing monoclonal antibodies use mouse cells, it is necessary to create humanized monoclonal antibodies for human clinical use. Mouse antibodies cannot be injected repeatedly into humans, because the immune system will recognize them as being foreign and will respond to them with neutralizing antibodies. This problem can be minimized by genetically engineering the antibody in the mouse B cell. The variable regions of the mouse light and heavy chain genes are ligated to human constant regions, and the chimeric gene is then transferred into a host cell. This allows production of a mAb that is mostly “human” with only the antigen-binding site being of mouse origin.

Questions & Answers

anybody tell me what is immobilization
rajesh Reply
immobilization means when anatomy of our body is deviated to correct as normal anatomical position ok!
the process in which we un able to move their body parts due to any reason such as nerve disorders .trauma etc
is there anybody here who know about Black Soldier Flies
Eyinfunjowo Reply
Hello everyone Am Sandra studying Microbiology in Nigeria How does this work?
Iyere Reply
in which university?
hello my name is najdah, im studying microbiology too
hello, my name is Puneet, im studying microbiology in GURUKUL KANGRI UNIVERSITY, HARIDWAR, INDIA
hello I m Rajesh I completed B.Sc.Chemistry also I Completed Post Graduation Diploma in fermentation and wine making Science tech
hello.. My name is Bahati..i m studying biomedical sciences here in zambia
hii ....I'm vinod I'm studying b.pharm in pune university
good to hear from you, I'm Joel studying Masters in Public health. Namibia
this is imtiaz afridi bsc in micro. graduate in nursing
i am from Pakistan
aim from Ethiopia health officer student
What is batch culture
Keerti Reply
a technique for large-scale production of microbes or microbial products.
use of bioreactors
a suspension culture in which cells grow in finite volume of nutrient medium following a sigmoidal pattern of growth
batch culture..... the microorganisms grows in a bunch colony
is there any book which can help in preparing for NET?
Moumita Reply
yes Michael J pleczar
it's a good book
Industrial production of microbial drugs
Funmi Reply
Hi!! I'm a Medical Technologist in Microbiologist from Cuba but I'm living in USA and I'm studying to get a License to start working here
Yailin Reply
im an ascpi licensed med tech working with my papers to work in US as well..hope i'll be one of the lucky candidates in H1b visa this year
Wish you all the luck dear even though I hardly know you..Go get what's yours and make your life greater than anything else...
thanks :)
You're welcome but never forget your own god.. pray Dear...
Ooh I'm inspired by Azora...God is everything..He is mighty and beyond all human knowledge
l'm Asiya from Nigeria studying microbiology
Asiya Reply
Hi! this over here is Azola from South Africa studying microbiology.It's all because I seek more knowledge in each and every living and non-living ongarnism....
Hi! I'm also studying Microbiology In India and I'm graduating this year.
guess im the only medical technologist here? :)
Yes my dear, I too guess you're the only one who's doinn' MEDI-TECH....
am maria from somlia student of lab guess welcome
am muslim alx also happy with meeting uuu
am amina a student of microbiology is my pleasure of meeting u guys here
welcome guys
imtiaz from pakista lecturer of microbiology and also graduate in nursing field
you can message on here?
oh i am also happy to meet u
Salam ..am Maryam, studying microbiological in Nigeria.
nice to meet you all
im student of microbiology
Hi... Am Japhet... Microbial scientists
Japhet Reply
how does this work i'm à little bit bored here!
didnt know it has an active chat box..downloaded this app to have something to read only..
what is shrimp
Rashmi Reply
a type of fish also called as prawn.
shellfish you eat tasty treat
Am Blessing from Nigeria studying microbiology
Ekeoma Reply
I am also microbiology
me too study microbiology
I completed my masters degree in microbiology .
I'm Favour from Nigeria,a Human Anatomist. Hope am welcomed here?
am Cynthia from Nigeria,am a graduate of applied microbiology and brewing.
Cynthia Reply
4. You are examining a cell on low power. You can see the cell membrane and nucleus. When you turn the microscope to high power, the cells become blurry and you can no longer identify any structures. What happened?
Jenny Reply
maybe need oil immersion
oil cuts dwn on light refraction.
for observing under high power a drop of oil must be put on the slide first
examination of past case histories and medical test results conducted on patients in an outbreak
shaletta Reply
my name is Yasini Mohamed from Tanzania, l am studying becholor of science in biology can I specialize to microbiology?
it could be hormonal in balanced kindly see a doctor thanks
Precious Reply

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Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
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