Why do we use eggs, not serum to produce our chicken antibodies?
Immunoglobulin Y (IgY) is the major circulating antibody in chickens, but it is also found in egg yolks at high concentrations. Consequently, Aves Labs chooses to use eggs exclusively as its source of chicken IgY antibodies because it is animal-friendly.
We never bleed our hens, and we do not have to perform cardiac puncture to obtain large quantities of antibodies. We simply collect eggs.
Hens natually transfer their circulating IgY antibodies into their eggs as a means of conferring passive immunity to their offspring. Although the egss used for antibody production at Aves Labs are not fertilized, they contain about 100 mg of IgY per yolk.
In summary, eggs provide a convenient and humane source of high quality chicken IgY antibodies.
How long does it take to make a high-quality chicken antibody?
Regardless of the host species used to raise antibodies, it takes time for the immune system to produce the maximum titre of antibodies.
The maximal-titre antibody production process takes about twelve (12) weeks -- the same in chickens as in rabbits. (This is because the cell biology of antibody induction is the same in all vertebrates.) Note that any company advertising faster production times likely is sacrificing high titres for speed. Aves Labs will not make this sacrifice, as we believe it does not serve our customers' best interests.
The 12-week production schedule includes:
- four (4) injections spaced about 2-3 weeks apart;
- an egg collection phase; and
- an IgY purification phase (for both immune and pre-immune antibodies).
Customers requesting that Aves Labs synthesize peptides and conjugate them to carrier proteins should add two (2) weeks to the production schedule (14 weeks total).
Customers requesting affinity purification and/or ELISA analysis should add an additional two (2) weeks (16 weeks total).
For examples of custom chicken IgY antibody generation, please take a look at our Customer Success Blog.
How much IgY is present in chicken eggs?
The concentration of antibody in the egg yolk is somewhat higher than that found in serum. Whereas human serum typically contains IgG at 10-12 mg/ml, egg yolk contains immunoglobulin Y (IgY) at 8-20 mg/ml (Akita and Nakai, 1993 J. Immunol Methods 160 (2), 207-214). It is thought that this high concentration is important for conferring passive immunity to newly hatched chicks.
The rate of antibody production in laying chickens is remarkable. According to Larsson et al (1993) (Poultry Science 72 (10), 1807-1812), in one week, a hen produces egg antibodies equivalent to 90-100 ml of serum." This article also states that "only large mammals, such as cows or horses, can produce more antibodies than a laying hen." Gassmann et al (1990) (FASEB Journal 4 (8), 2528-2532) states that "the amount of purified IgY produced in one month is 18 times higher than that of IgG produced in a rabbit."
Therefore, chicken IgY isolated from egg yolk is a humane and economical source of large quantities of high quality antibodies.
What is the difference between the "IgY Fraction” and the “Affinity-Purified Antibody Fraction?"
Some of our chicken IgY antibodies are supplied as an "IgY fraction," while many are supplied as an "affinity-purified antibody fraction."
The IgY fraction refers to the total complement of antibodies circulating in the hen’s egg yolk.
The "affinity-purified antibody fraction" refers to only those antibodies that bind to the immunizing antigen (protein or peptide) with high affinity. They are typically purified using the immunizing antigen covalently immobilized on agarose beads. These affinity-purified antibodies typically correspond to 0.5%-2.0% of the total complement of antibodies.