Polyclonal FAQ’s

Q: Which species should I use for polyclonal antibody production?

A: Several factors are considered when determining the best species for polyclonal antibody production. If a protein antigen is homologous to a protein found in the species being immunized, a different species should be considered. For example, chickens frequently generate antibodies to conserved mammalian proteins. The amount of antibody required also determines the appropriate host species. Small amounts of sera containing antibody are obtained from mice, rats and guinea pigs. Larger amounts of sera are obtained from rabbits, the most popular species at SDIX for immunization. The largest volumes of sera (or plasma) are obtained from sheep and goats. Also, consider the time required to obtain a fully-matured antibody response. Rabbits, chickens, guinea pigs, rats, and mice typically require 4 immunizations over approximately 70 days to reach optimal immune response. Goats and sheep require more immunizations over 200 days to reach full immune maturity.

Q: What type of antigens can be used for polyclonal antibody production?

A: Nearly any molecule can be injected into animals, but some molecules are much better immunogens than others. Full-length proteins, either expressed recombinantly or purified from natural sources, are the best immunogens. Peptides may be easier and cheaper to produce, but anti-peptide antibodies frequently fail to recognize the full-length protein from which they were derived. Small molecules such as vitamins, antibiotics, drugs, dyes, and metabolites are not immunogenic due to their small size. This class of antigen is known as haptens. Haptens must be conjugated to carrier proteins before they can be recognized by the immune system. Other molecules such as carbohydrates, lipoproteins, and phospholipids are poor immunogens, either generating undesirable IgM responses only or failing to generate any response.

Q: To make large volumes of antisera, should I start additional animals or should I use extended immunization protocols on fewer animals?

A: Consider your timeline and consider the amount of antibody you require in a single lot of antibody product. If large amounts of antibody are required in a short period of time, more animals are started on an immunization protocol. If a single large lot of antibody product is desired, more animals are started on an immunization protocol. A single large lot of antibody minimizes the amount of qualification testing required before use in your laboratory or manufacturing operation. If you are uncertain of the antibody response that will be elicited by your antigen, extended immunization protocols may be preferable. In this approach, several animals might be started on a standard immunization protocol. At the conclusion of the standard protocol, the animals with the best antibody response are continued on extended protocols.

Q: How can I determine the status of my project?

A. You can contact your SDIX Customer Service Representative during business hours by phone, fax or email. When your project initiates your CS Representative will also assign you a password to our secure STAR database allowing you 24/7 web based access to your project information. With this access you will be able to see real time events completed or scheduled for your project, this information can be downloaded for your records.

Q: What level of compliance does SDIX have regarding animal welfare regulations?

A. SDIX has PHS/NIH/ OLAW Animal Welfare Assurance which allows SDIX to provide services to researchers with federal grants. In addition, SDIX maintains 4 separate licenses/registrations with the USDA and is an AAALAC accredited institution, maintaining the highest animal welfare standards. SDIX is also ISO 13485:2003 certified. SDIX utilizes Specific Pathogen Free (SPF) rabbit and small animal species to protect your project investment. Although goats, sheep and chickens are non-SPF, SDIX maintains high levels of bio-security monitoring and disease prevention programs for all species.

Q: What if I need large volumes of antisera?

A. Rabbits and goats are both utilized for large volume products. Rabbits can provide up to a half liter of antisera per year as compared to a goat or sheep that may produce up to 30 liters annually. SDIX utilizes continuous flow plasmapheresis for antisera collection from goats and sheep. Continuous flow plasmapheresis allows the return of red cells, white cells and platelets to the donor animal, the volume of plasma extracted is replaced with supportive fluids. This sterile procedure utilizes state of the art plasma collection technology. This process maintains the health of the animal while maximizing available antisera.

Q: What if I need project customization?

A. SDIX’s Polyclonal facility has been in operation for over 43 years producing antibodies. This experience can be applied to your project when designing antigens and antibody production. Our scientists can provide technical assistance with antigen and antibody project design to maximize your project results. Customization of immunization protocols, antisera processing and laboratory services are available and include adjuvant selection, injection routes/volumes/frequencies, labeling/vialing/sampling of antisera, and purification and screening options.


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