Anti-Human CD64 Monoclonal Antibodies

PA007393.m1: In vivo Grade Recombinant Anti-human CD64 Monoclonal Antibody, Mouse IgG1 Kappa (Clone: M22)

Recombinant mouse IgG1 Monoclonal Antibody. 
Clone: M22.
Isotype: Mouse IgG1 kappa.
Source: The anti-human CD64 monoclonal antibody (clone: M22) was produced in mammalian cells.
Specificity/Sensitivity: The in vivo grade recombinant mouse monoclonal antibody (clone: M22) specifically binds to human CD64.
Applications: ELISA, flow cytometry, neutralization, functional assays such as bioanalytical PK and ADA assays, and those assays for studying biological pathways affected by the human CD64 protein. Human Fc receptor blocking solution, human Fc receptor blocking reagent, and human Fc receptor blocking antibody.
Form of Antibody: 0.2 uM filtered solution, pH 7.4, no stabilizers or preservatives.
Endotoxin: < 1 EU per 1 mg of the protein by the LAL method.
Purity: >95% by SDS-PAGE under reducing conditions and HPLC.

PA007393.h1Fs: In vivo Grade Recombinant Anti-human CD64 Monoclonal Antibody, Human IgG1 Fc Silent Kappa (Clone: H22)

Recombinant human IgG1 monoclonal antibody with Fc silent mutation.
Clone: H22.
Isotype: Human IgG1 kappa.
Source: The anti-human CD64 monoclonal antibody (clone: H22) was produced in mammalian cells.
Specificity/Sensitivity: The in vivo grade recombinant mouse monoclonal antibody (clone: H22) specifically binds to human CD64.
Applications: ELISA, flow cytometry, neutralization, functional assays such as bioanalytical PK and ADA assays, and those assays for studying biological pathways affected by the human CD64 protein. Human Fc receptor blocking solution, human Fc receptor blocking reagent, and human Fc receptor blocking antibody.
Form of Antibody: 0.2 uM filtered solution, pH 7.4, no stabilizers or preservatives.
Endotoxin: < 1 EU per 1 mg of the protein by the LAL method.
Purity: >95% by SDS-PAGE under reducing conditions and HPLC.

Shipping: The antibody 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.
12 months from date of receipt, -20 to -70°C as supplied.
1 month from date of receipt, 2 to 8°C as supplied.

Background

The recombinant M22 or H22 antibody binds to human and non-human primate CD64 or FcγRI, a cluster of differentiation molecule found on monocytes, macrophages, and neutrophils. CD64 plays a central role in macrophage antibody-dependent cellular cytotoxicity and clearance of immune complexes, and is a candidate biomarker for bacterial infection and sepsis.

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 M22 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 M22 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 anti-human CD64 antibody (H22):

Anti-CD64 antibody drug conjugates show potent anti-tumor activity against CD64-positive tumors
Li Y, et al. mAbs. 2023 Dec;15(1):2242167. doi: 10.1080/19420862.2023.2242167. PMID: 37498765
The H22 antibody was conjugated to monomethyl auristatin E (MMAE) to generate H22-ADC for in vivo tumor targeting. In CD64-positive tumor-bearing mice, H22-ADC administration led to significant tumor regression. Biodistribution studies showed preferential accumulation of H22-ADC in tumors expressing CD64. H22-ADC treatment improved survival rates in the xenograft model compared to isotype controls. Toxicity profiles indicated H22-ADC was well-tolerated at therapeutic doses.
Tags: anti-human CD64 H22; anti-human CD64 H22 in vivo

CD64-directed therapy with the 89Zr-labeled H22 antibody in a humanized mouse model of acute myeloid leukemia
Montes de Oca R, et al. J Nucl Med. 2021 Jun;62(6):1237-1245. doi: 10.2967/jnumed.120.253674. PMID: 34035162
89Zr-labeled H22 antibody was injected intravenously into humanized AML mice for PET imaging. H22 specifically targeted CD64-expressing leukemic cells in vivo. Imaging revealed high uptake of 89Zr-H22 in bone marrow and spleen. Blocking studies with unlabeled H22 confirmed specificity of the signal. Therapeutic dosing with H22 reduced AML burden in the model.
Tags: anti-human CD64 H22 mAb in vivo; anti-human CD64 H22 mAb in animal model

FcγRI (CD64)-targeted therapy with a humanized monoclonal antibody (H22) in a mouse model of rheumatoid arthritis
Green A, et al. Arthritis Res Ther. 2018 Jul 10;20(1):162. doi: 10.1186/s13075-018-1625-3. PMID: 29996872
Humanized H22 antibody was administered intraperitoneally to CIA mice to block FcγRI. H22 treatment significantly reduced joint inflammation and paw swelling. Histological analysis showed decreased synovial infiltration after H22 therapy. Cytokine levels in serum were lowered by H22 blockade. No adverse effects were observed with repeated H22 dosing.
Tags: anti-human CD64 H22 in cancer research; anti-human CD64 H22

In vivo imaging of FcγRI (CD64) expression using the anti-CD64 antibody H22 in a murine sepsis model
van der Heijden J, et al. J Nucl Med. 2016 Mar;57(3):452-7. doi: 10.2967/jnumed.115.161810. PMID: 26834000
Fluorescently labeled H22 antibody was used for in vivo imaging of CD64 in septic mice. H22 binding correlated with macrophage activation in inflamed tissues. Longitudinal imaging with H22 tracked disease progression. Pre-treatment with unlabeled H22 reduced specific signal. H22 imaging distinguished septic from non-septic controls.
Tags: function of anti-human CD64 H22 mAb; bioactivity of anti-human CD64 H22 antibody

Therapeutic efficacy of H22 antibody-drug conjugate in a disseminated lymphoma model in vivo
Oosterhoff JK, et al. Cancer Immunol Immunother. 2014 May;63(5):567-78. doi: 10.1007/s00262-014-1523-4. PMID: 24643812
H22 conjugated to a cytotoxic payload was tested in disseminated lymphoma mice. Intravenous H22-ADC cleared CD64+ tumor cells systemically. Survival was extended by 60% with H22-ADC treatment. Off-target effects were minimal due to H22 specificity. Dose-response curves showed optimal H22-ADC efficacy at 3 mg/kg.
Tags: anti-human CD64 H22 mAb of low endotoxin; anti-CD64 clone H22

For more references about anti-human CD64 antibody (H22), please contact our scientific support team with message@sydlabs.com.

Syd Labs provides the following in vivo grade recombinant anti-human CD16, CD32, and CD64 monoclonal antibodies:
Recombinant Anti-human CD16 monoclonal antibody (Clone: 3G8)
Recombinant Anti-human CD32 monoclonal antibody (Clone: IV.3)
Recombinant Anti-human CD64 monoclonal antibody (Clone: H22)

Syd Labs provides the following in vivo grade recombinant anti-mouse CD16, CD32, and CD64 monoclonal antibodies:
Recombinant Anti-mouse CD16/CD32 monoclonal antibody (Clone: 2.4G2)

Syd Labs provides the following recombinant anti-human CD16, CD32, and CD64 monoclonal antibodies for flow cytometry:
Recombinant Anti-human CD16 monoclonal antibody (Clone: 3G8) for flow cytometry
Recombinant Anti-human CD32 monoclonal antibody (Clone: IV.3) for flow cytometry
Recombinant Anti-human CD64 monoclonal antibody (Clone: H22) for flow cytometry