Recombinant Human IgG Isotype Control Antibodies

Recombinant human IgG isotype control antibodies help minimize non-specific binding of primary and capture antibodies by blocking interactions between antibody Fc fragments and Fc receptors, and preventing non-specific antibody binding to cellular proteins, carbohydrates, and lipids. Normal human serum and purified human IgGs from normal human serum are commonly used as non-specific passive blocking solution for antibody-based immuno-assays. Recombinant human IgG antibody mixes, as a direct alternative to normal human serum and even human IgGs purified from human serum or a non-specific passive blocking solution, can be used to eliminate interfering antibodies from immuno-assay systems using capture and detection antibodies. There is higher percentage of human IgG1 in normal human serum.

Features of recombinant human IgG isotype control antibodies compared with normal human serum and serum-derived human IgGs:

1) Animal free production. CHO cells rather than human are used in antibody production.

2) Lot-to-lot consistency. CHO cells which are used for antibody drug manufacturing are used to manufacture the human IgG isotype control antibodies in the antibody mixes. All production is under control and predictable.

3) As a targeted or passive antibody blocker to interfering antibodies and no binding to human tissues. In contrast, some serum-derived human IgGs may bind to unknown targets in some human tissues.

4) Adjustable percentages of the recombinant human IgG isotype control antibodies in the recombinant human IgG antibody mixes. A customized recombinant human IgG antibody mix with different percentages of human IgG1, IgG2, IgG3, and IgG4 isotype control antibodies can be easily made according to customers' applications.

Recombinant human IgG isotype control antibodies are the best normal human serum alternative as blocking reagents, and serum-derived human IgGs alternative.

PA007405: Recombinant Human IgG1 Isotype Control Antibody

The recombinant anti-HEL human IgG1 isotype control antibody binds to neither human nor mouse samples.
Clone: HyHEL-10.
Isotype: human IgG1 kappa.
Specificity/Sensitivity: neither human nor mouse samples.
Applications: ELISA, flow cytometry, immunoblotting, immunoprecipitation, immunocytochemistry, immunofluorescence, and isotype controls. 
Reactivity: None of Human, Mouse, and Rat.
Purification: The recombinant human IgG1 isotype control antibody was affinity-purified from supernatant of mammalian cells cultured in a chemically defined medium by affinity-chromatography using protein A.
Form of Antibody: 1x PBS.
Purity: >95% by SDS-PAGE under reducing conditions.

PA007406: Recombinant Human IgG2 Isotype Control Antibody

The recombinant human IgG2 isotype control antibody binds to neither human nor mouse samples.
Isotype: human IgG2 kappa.
Specificity/Sensitivity: neither human nor mouse samples.
Applications: ELISA, flow cytometry, immunoblotting, immunoprecipitation, immunocytochemistry, immunofluorescence, and isotype controls. 
Reactivity: None of Human, Mouse, and Rat.
Purification: The recombinant human IgG2 isotype control antibody was affinity-purified from supernatant of mammalian cells cultured in a chemically defined medium by affinity-chromatography using protein A and G.
Form of Antibody: 1x PBS.
Purity: >95% by SDS-PAGE under reducing conditions.

PA007407: Recombinant Human IgG3 Isotype Control Antibody

The recombinant human IgG3 isotype control antibody binds to neither human nor mouse samples.
Isotype: human IgG3 kappa.
Specificity/Sensitivity: neither human nor mouse samples.
Applications: ELISA, flow cytometry, immunoblotting, immunoprecipitation, immunocytochemistry, immunofluorescence, and isotype controls. 
Reactivity: None of Human, Mouse, and Rat.
Purification: The recombinant human IgG3 isotype control antibody was affinity-purified from supernatant of mammalian cells cultured in a chemically defined medium by affinity-chromatography using protein A and G.
Form of Antibody: 1x PBS.
Purity: >95% by SDS-PAGE under reducing conditions.

PA007408: Recombinant Human IgG4 (S228P) Isotype Control Antibody

The recombinant human IgG4 isotype control antibody binds to neither human nor mouse samples.
Isotype: human IgG4 kappa.
Specificity/Sensitivity: neither human nor mouse samples.
Applications: ELISA, flow cytometry, immunoblotting, immunoprecipitation, immunocytochemistry, immunofluorescence, and isotype controls. 
Reactivity: None of Human, Mouse, and Rat.
Purification: The recombinant human IgG4 isotype control antibody was affinity-purified from supernatant of mammalian cells cultured in a chemically defined medium by affinity-chromatography using protein A.
Form of Antibody: 1x PBS.
Purity: >95% by SDS-PAGE under reducing conditions.

Shipping: The recombinant human IgG isotype control antibodies are 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. For maximum recovery of the product, centrifuge the original vial after thawing and before removing the cap.
1 month from date of receipt, 2 to 8°C as supplied.
12 months from date of receipt, -20°C to -70°C as supplied.

The most popular human Fc blocking reagents include:
Anti-human CD16 (clone 3G8), and CD32 (Clone IV.3): for flow cytometry, immunohistochemistry (IHC), and immunoprecipitation (IP). It is highly specific for FcγRII (CD32) and FcγRIII (CD16), and reduces background staining; it may not block all Fc receptors. Clones 10.1, and 22 or H22 are the most widely used anti-human FcγRI (CD64) clone for Fc blocking in flow cytometry and functional assays. It prevents non-specific Fc receptor binding on monocytes, macrophages, and dendritic cells, improving antibody specificity.
Purified human IgGs or mixes of human isotype controls: for general Fc blocking in IHC and immunofluorescence (IF). It is cheap and easy to use but it is less specific, and may even introduce unwanted immunoglobulins. Syd Labs supply various human IgG isotype controls.
Normal mouse serum, purified mouse IgG or isotype controls: for flow cytometry. It can serve as a control to block Fc receptors but it is non-specific for Fc receptors. It is cheap and easy to use but it is less specific, and may even introduce unwanted immunoglobulins. Our recombinant mouse IgG antibody mixes are affordable; the ratio of various IgGs is optimized and adjustable without any unwanted immunoglobulins.
Bovine Serum Albumin (BSA) or FBS: for general blocking in Western Blot (WB) and IHC. They are readily available to reduce non-specific binding but less effective at Fc receptor blocking.
Commercial Fc blocking solutions: for flow cytometry, IHC, and functional assays. They are normally pre-optimized and highly effective but more expensive than DIY solutions. 

Best choice of human Fc blocking reagents based on your application are:
For flow cytometry: anti-human CD16 (Clone 3G8), CD32 (Clone IV.3), and CD64 (Clone 10.1, and 22 or H22).
For Immunohistochemistry (IHC) and Immunofluorescence (IF): Normal mouse serum, purified mouse or human IgGs or isotype controls or commercial Fc blocking kits. Our recombinant mouse IgG antibody mixes and recombinant human IgG isotype controls are affordable; the ratio of various IgGs is optimized and adjustable without any unwanted immunoglobulins.
For Western Blot and ELISA: BSA or FBS.
For functional assays (e.g., blocking Fc-mediated effects): Commercial Fc blocking reagents.

References of Human IgG Isotype Control Antibody:

Fcγ-Receptor-Independent Controlled Activation of CD40 Canonical Signaling by Novel Therapeutic Antibodies for Cancer Therapy
Beckmann K, et al. Antibodies (Basel). 2024 Apr 18;13(2):31. doi: 10.3390/antib13020031. PMID: 38651411
However, even immunomodulatory antibodies on the human IgG4 background may interact with cellular FcγRs and show dose limiting toxicities. By using a humanized mouse model allowing to study the immunomodulatory activity of human checkpoint control antibodies in vivo, we demonstrate that deglycosylation of the CD137-specific IgG4 antibody urelumab results in an amelioration of liver toxicity. The antibodies were administered intravenously to tumor-bearing mice at doses of 10 mg/kg weekly. Tumor growth was monitored over 4 weeks, showing significant inhibition in the treatment group. Histological analysis of liver tissues revealed reduced inflammation in deglycosylated antibody-treated mice compared to controls.
Tags: activity of Human IgG Isotype Control; activity of Human IgG Isotype Control mAb

Of mice and men: the need for humanized mouse models to study human IgG activity in vivo
de Taeye SW, et al. Immunol Rev. 2012 Sep;250(1):164-80. doi: 10.1111/j.1600-065X.2012.01143.x. PMID: 22948744
Antibodies of the IgG isotype have a variety of pro- and anti-inflammatory effector functions, making them attractive platforms for the development of novel therapeutic approaches. Animal model systems have been invaluable to the understanding of the underlying mechanisms of IgG activity. However, differences in the IgG subclasses and Fc receptors responsible for mediating IgG-dependent effector functions, even between such closely related species as humans and monkeys, make it difficult to predict the activity of human IgG in vivo. Humanized mice engrafted with human immune cells were used to evaluate human IgG effector functions in a transplant model. In vivo depletion of target cells was observed only with human IgG1 subclasses in the humanized model.
Tags: Human IgG Isotype Control antibody; Human IgG recombinant isotype control

Effects of CAMPATH-1 antibodies in vivo in patients with lymphoid malignancies: influence of antibody isotype
Dyer MJ, et al. Blood. 1989 May 15;73(7):1431-9. doi: 10.1182/blood.V73.7.1431.1431. PMID: 2713487
The CAMPATH-1 family of antibodies recognize an abundant glycoprotein expressed on virtually all human lymphocytes. All rat IgM and IgG antibodies of this specificity are lytic with human complement, but only IgG2b is active in antibody-dependent cell-mediated cytotoxicity (ADCC). We compared the ability of IgM, IgG2a, and IgG2b to deplete lymphocytes in vivo in two patients with prolymphocytic transformation of B-cell chronic lymphocytic leukemia (CLL). Patients received intravenous infusions of 10-100 mg of antibody over 1-7 days. Peripheral blood lymphocyte counts fell rapidly after treatment, with IgG2b showing the most profound and sustained depletion.
Tags: Human IgG Isotype Control antibody for cancer research; Human IgG Isotype Control antibody for flow cytometry

In vivo polysaccharide-specific IgG isotype responses to intact Streptococcus pneumoniae are T cell dependent and require CD40- and B7-ligand interactions
McCool TL, et al. J Immunol. 1999 Jul 15;163(2):1180-8. PMID: 10395655
In vivo Ig responses to soluble, haptenated polysaccharide (PS) Ags are T cell independent and do not require CD40 ligand (CD40L). However, little is known regarding the regulation of in vivo PS-specific Ig responses to intact bacteria. We immunized mice with a nonencapsulated, type 2 Streptococcus pneumoniae (R36A) and compared the parameters that regulated in vivo Ig isotype responses to the bacterial cell wall C-PS determinant, phosphorylcholine (PC). Mice were immunized intraperitoneally with 10^8 CFU of R36A bacteria. Serum IgG anti-PC titers were measured by ELISA seven days post-immunization, showing T cell dependence.
Tags: Human IgG Isotype Control antibody in vivo; Human IgG Isotype Control for animal model

FcγRIV deletion reveals its central role for IgG2a and IgG2b activity in vivo
Nimmerjahn F, et al. Proc Natl Acad Sci U S A. 2007 Aug 28;104(35):13482-7. doi: 10.1073/pnas.0706690104. PMID: 17703414
To define the role of the recently identified FcγRIV for IgG activity in vivo, we generated FcγRIV-deficient mice. In vivo, IgG2a- and IgG2b-mediated effector functions were strongly reduced in FcγRIV-/- mice. Wild-type and FcγRIV-/- mice were injected with IgG-opsonized red blood cells intravenously. Clearance of opsonized cells was monitored by flow cytometry of blood samples over 24 hours. In FcγRIV-/- mice, clearance rates were significantly slower for IgG2a and IgG2b compared to wild-type controls.
Tags: function of Human IgG Isotype Control; Human IgG Isotype Control antibody mouse dose range

For more references about Human IgG Isotype Control Antibody, please contact our scientific support team with message@sydlabs.com.

Syd Labs provides the following anti-human Fc blocking reagents:
Anti-human CD16 monoclonal antibody (Clone: 3G8)
Anti-human CD32 monoclonal antibody (Clone: IV.3)
Anti-human CD64 monoclonal antibody (Clone: 22)
Purified human IgG
Recombinant human IgG antibody mixes
Recombinant human IgG isotype control antibodies
Recombinant mouse IgG antibody mixes
Recombinant mouse IgG isotype control antibodies
Recombinant rat IgG antibody mixes
Recombinant rat IgG isotype control antibodies

Syd Labs provides the following anti-mouse Fc blocking reagents:
Anti-mouse CD16/CD32 monoclonal antibody (Clone: 2.4G2)
Recombinant mouse IgG antibody mixes
Recombinant mouse IgG isotype control antibodies
Recombinant rat IgG antibody mixes
Recombinant rat IgG isotype control antibodies