Description

Mouse IgG2a isotype control and mutants (natural and engineered mIgG2a isotype controls) are useful for in vitro and in vivo studies from ELISA, Western blot (WB), to cell-based assay to animal model study. Mouse IgG2a antibodies are similar to human IgG1 antibodies in many aspects; thus researchers like to use the isotype of mouse IgG2a in mouse studies. Most of the therapeutic antibody drugs carry the natural human IgG1 constant regions. More and more engineered mutants in the human IgG1 Fc fragment have been tested during therapeutic antibody drug development. The corresponding mutations have been introduced to mouse IgG2a to study enhancement and abrogation effects of Fc binding. We generated mIgG2a isotype control mutants, the same mutations as those in therapeutic antibodies and candidates because such mouse IgG2a isotype control mutants are needed when clients test their engineered antibody candidates. For example, P329G substitution combined with L234A L235A (mIgG2a LALAPG, Fc silenced) was shown to decrease effector functions by disrupting the Fc/Fcγ receptor interface.
The ideal recombinant mouse IgG2a isotype control has low or no specific binding to any mouse sample, and completely mouse variable regions and the mouse IgG2a kappa constant regions. The mouse IgG2a kappa isotype control and mutants can be used in ELISA, Western blot (WB), the cell-based assay or animal model as the antibody negative control.
Please contact us to ask for a quote for the engineered mouse IgG2a isotype control mutants, mIgG2a isotype control and mutants with Avi-, His-, and Flag-tags, and biotinylated mIgG2a isotype control and mutants. A variety of conjugates (such as dyes and fluorophores) with the mouse IgG2a isotype control and mutants are available.

SA129: In Vivo Grade Recombinant Mouse IgG2a Isotype Control Antibody (mIgG2a Isotype Control)

The in vivo grade recombinant mouse IgG2a isotype control antibody (mIgG2a isotype control) was produced in mammalian cells.
Immunogen: N/A.
Clone: 12B9.
Isotype: mouse IgG2a, kappa.
Applications: an isotype-matched negative control for mouse IgG2a kappa antibodies used in ELISA, Western Blot (WB), Flow Cytometry (Flow), Immunoprecipitation (IP), Immunohistochemistry (Paraffin) (IHC (P)), Immunohistochemistry (Frozen) (IHC (F)), and in vivo animal model research.
Formulation: 0.2 μM filtered solution of 1x PBS.
Purity: >95% by SDS-PAGE under reducing conditions.
Endotoxin: Less than 1 EU/mg of protein as determined by LAL method.

SA136: In Vivo Grade Recombinant Mouse IgG2a-D265A Isotype Control Antibody (mIgG2a D265A Isotype Control)

The in vivo grade recombinant mouse IgG2a-D265A isotype control mutant (mIgG2a D265A isotype control) was produced in mammalian cells.
Immunogen: N/A.
Clone: 12B9.
Isotype: mouse IgG2a, kappa.
Applications: an isotype-matched negative control for mouse IgG2a D265A kappa antibodies used in ELISA, Western Blot (WB), Flow Cytometry (Flow), Immunoprecipitation (IP), Immunohistochemistry (Paraffin) (IHC (P)), Immunohistochemistry (Frozen) (IHC (F)), and in vivo animal model research.
Formulation:0.2 μM filtered solution of 1x PBS.
Purity: >95% by SDS-PAGE under reducing conditions.
Endotoxin: Less than 1 EU/mg of protein as determined by LAL method.

SA137: In Vivo Grade Recombinant Mouse IgG2a-N297A Isotype Control Antibody (mIgG2a N297A Isotype Control)

The in vivo grade recombinant mouse IgG2a-N297A isotype control mutant (mIgG2a N297A isotype control) was produced in mammalian cells.
Immunogen: N/A.
Clone: 12B9.
Isotype: mouse IgG2a, kappa.
Applications: an isotype-matched negative control for mouse IgG2a N297A kappa antibodies used in ELISA, Western Blot (WB), Flow Cytometry (Flow), Immunoprecipitation (IP), Immunohistochemistry (Paraffin) (IHC (P)), Immunohistochemistry (Frozen) (IHC (F)), and in vivo animal model research.
Formulation: 0.2 μM filtered solution of 1x PBS.
Purity: >95% by SDS-PAGE under reducing conditions.
Endotoxin: Less than 1 EU/mg of protein as determined by LAL method.

SA138: In Vivo Grade Recombinant Mouse IgG2a-L234A L235A P329G Isotype Control Antibody (mIgG2a LALAPG Isotype Control)

The in vivo grade recombinant mouse IgG2a-L234A L235A P329G (mIgG1 LALAPG, Fc silenced) isotype control mutant (mIgG2a LALAPG isotype control) was produced in mammalian cells.
Immunogen: N/A.
Clone: 12B9.
Isotype: mouse IgG2a, kappa.
Applications: an isotype-matched negative control for mouse IgG2a LALAPG kappa antibodies used in ELISA, Western Blot (WB), Flow Cytometry (Flow), Immunoprecipitation (IP), Immunohistochemistry (Paraffin) (IHC (P)), Immunohistochemistry (Frozen) (IHC (F)), and in vivo animal model research.
Formulation: 0.2 μM filtered solution of 1x PBS.
Purity: >95% by SDS-PAGE under reducing conditions.
Endotoxin: Less than 1 EU/mg of protein as determined by LAL method.
Shipping: The product is shipped with ice pack. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
1 month from date of receipt, 2 to 8°C as supplied.
3 months from date of receipt, -20°C to -70°C as supplied.

Background

Mouse IgG antibodies are classified to four subclasses mainly based on the isotype of the heavy chain (IgG1, IgG2a or IgG2c, IgG2b, and IgG3 for the heavy chain; kappa and lamda for the light chain), of which IgG1 and kappa are the most abundant named in serum. IgG antibodies are large molecules of about 150 kDa composed of four peptide chains, two identical heavy chains of about 50 kDa and two identical light chains of about 25 kDa. The four peptides are arranged in a Y-shape tetramer by disulfide bonds formed between the two heavy chains and between a heavy chain and a light chain.

Questions and Answers:

Question:The monoclonal antibody produced by the hybridoma C1.18.4 (clone number) is used as a mouse IgG2a kappa isotype control. The antibody variable regions of MOPC21 (hybridoma clone number, isotype: mouse IgG1, kappa) are used to make a recombinant mouse IgG2a kappa isotype control. Both C1.18.4 and MOPC21 antibodies have unknown binding specificity. Is your isotype control the C1.18.4 or MOPC21 antibody?

Answer: Our recombinant mouse IgG1 isotype controls (catalog # SA129 and the mutants) are not from C1.18.4 or MOPC21 though we also produce and sell the recombinant C1.18.4 and MOPC21 mouse IgG2a isotype controls. Please contact us and ask for C1.18.4 and MOPC21 derived recombinant mouse IgG2a kappa isotype controls if you are interested.

Question: What is the advantage of the recombinant antibody production method compared to the other antibody production method(s)?

Answer: We use chemically defined medium for cell culturing to produce the recombinant antibody. There is a significant advantage of the in vitro method. First, we do not use mouse ascites for antibody production. Second, although antibodies can be produced by cell culturing from over 90% of hybridomas, there is a finite and significant failure rate. The recombinant method can be of help. Third, some companies and scientists add FBS into hybridoma cell culturing medium, which results in antibody contamination. There is no such contamination in the production of recombinant antibodies. Fourth, we can easily switch the isotype with different antibody constant regions and generate mutations such as D265A which is used in therapeutic antibody research. It is better to use the same isotype control mutation.

Question: What is an isotype control antibody and why is it used?

Answer:An ideal isotype control matches the isotype of the primary antibody used in the application but lacks binding to the target. It is normally used as a negative control to differentiate any non-specific background signal from the specific antibody signal. Mouse IgG1 kappa isotype controls against KLH, TNP, DNP, GST, HEL, His-tag, Flag, c-myc, HA, and GFP meet the requirements in some cases but not in specific cases in the presence of the specific targets or cross-reactivity.