Homozygous: B cells from these mice fail to class switch so mice do not develop IgG responses
Hetero/Hemizygous: Immunization with NP-CGG (nitrophenol conjugated to chicken gamma globulin) yielded anNP-specific IgM antibody titer that was slightly higher in sera of AID-/- chimera than those of AID+/- chimera. However, no anti-NP IgG1 was produced by AID-/- chimera. MLN RNA (VH186.2-NP response) from AID+/- and AID-/- chimeras showed that AID+/- derived VH186.2 sequences of the mu and gamma1 chains carried comparable levels of mutation in the total and framework regions. However, CDR of the AID+/- gamma1 chain contained a 60% higher frequency of mutations than that of the AID+/- mu chain. R/S ratios were higher in CDR than framework region of both mu and gamma1 chains of AID+/- VH186.2 sequences. Furthermore, AID+/- VH186.2 sequences of the gamma1 chain contained, more frequently than those of the mu chain, the characteristic mutation at 33Trp (TGG) to 33Leu (TTG), which is known to be responsible for high-affinity binding to the NP hapten By contrast, AID-/- mu chains contained 10 times fewer mutations than AID+/- mu chain. There were no mutations in CDR 1 and CDR 2 of the AID-/- VH186.2 mu chain. The mutation frequency (1.5 x 10e-3) of AID-/- VH186.2 sequences was comparable to that due to PCR by Taq.
In this strain, activation-induced cytidine deaminase (Aicda - Gene ID 116298) was disrupted. To that end TT2 embryonic stem cells (strain of origin: (C57BL/6NCrlj x CBA/JNCrlj)F1) were electroporated with a target vector (see Fig. 2A in PMID:11007474) designed to replace exon 2 and the 5’ half of exon 3 with the neomycin resistance (NeoR) gene. Homologous integration was confirmed by PCR screening and Southern blot hybridization. ES cells were injected into ICR 8-cell embryos and implanted into pseudopregnant females. The resulting founder chimeras were crossed into C57BL/6 background to generate C57BL/6-Aicda‑/-mice, which were further crossed to MRL/MpJ-Faslpr/J(“MRL/lpr” - JAX Stock #000485) for 12 generations, then intercrossed to generate final strain. To prevent MRL/lpr drift, the animals were backcrossed to JAX Stock #000485 every 2 years.
|Viability and Fertility:||Female||Male||Comments|
|Homozygotes are viable:||Yes||Yes|
|Homozygotes are fertile:||Yes||Yes|
|Heterozygotes are fertile:||Yes||Yes|
|Age Reproductive Decline:||Less than 4 months||4 to 6 months|
Limited quantities of breeder mice (recovered litter) are available from a cryoarchive; recovered litter usually available to ship in 3 to 4 months.
Distribution of this strain requires submission of the MMRRC Conditions of Use (COU). A link to the COU web form will be provided via email after an order has been placed; the form should be completed then or the email forwarded to your institutional official for completion.
The donor or their institution limits the distribution to non-profit institutions only.
Additional charges may apply for any special requests. Shipping costs are in addition to the basic distribution/resuscitation fees. Information on shipping costs and any additional charges will be provided by the supplying MMRRC facility.
|MMRRC Item #||Description||Distribution Fee / Unit (US $)||Units||Notes|
|043606-UNC-RESUS||Litter recovered from cryo-archive||$2,829.00 / Non-Profit||Litter||Recovered litter1; additional fees for any special requests.|
Some MMRRC strains were submitted by the donor as cryopreserved germplasm, and because these strains were not cryopreserved by the MMRRC, we have not assessed the quality of this material. We have extensive experience with recovery of mice from cryopreserved sperm and embryos of varying quality, including using techniques such as IVF and ICSI, and are confident that we will have success in most, if not all, cases. However, because of the unknown quality of these frozen samples, we will restrict recovery efforts to two attempts for each order. Subsequent attempts can be performed on a fee-for-service basis, in addition to the standard fees, upon request.
1 The distribution fee covers the expense of resuscitating mice from the cryo-archive; you will receive the resulting litter. The litter will contain at minimum one mutant carrier; the actual number of animals and the gender and genotype ratios will vary. (Typically, multiple breeder pairs can be established from the recovered litter.) Prior to shipment, the MMRRC will provide information about the animals recovered. If you anticipate or find that you need to request specific genotypes, genders or quantities of mice in excess of what is likely from a resuscitated litter, you may discuss available options and pricing with the supplying MMRRC facility.
2 An aliquot is one straw or vial with sufficient sperm to recover at least one litter of mice, as per provided protocols, when performed at the MMRRC facility. The MMRRC makes no guarantee concerning the success of these procedures when performed outside the MMRRC facilities.
3 An aliquot contains a sufficient number of embryos (in one or more vials and based on the transfer success rate of the MMRRC facility) to transfer to at least two recipients. The MMRRC makes no guarantee concerning embryo transfer success experienced in the recipient investigator's laboratory. Neither gender nor genotype ratios are guaranteed.