Anti-Mouse PD-L1 [Clone 10F.9G2] — Purified in vivo PLATINUM™ Functional Grade

Clone 10F.9G2 is a rat monoclonal antibody that specifically targets mouse PD-L1 (programmed death ligand 1), also known as B7-H1 or CD274. This antibody is widely used in various in vivo applications involving mice, including:

Common In Vivo Applications

1. Blocking PD-L1 Interactions: The 10F.9G2 antibody is used to disrupt the interaction between PD-L1 and its receptors, such as PD-1 and B7-1 (CD80), to modulate immune responses.

2. Immunohistochemistry (IHC): It can be used for the detection of PD-L1 expression in mouse tissues, providing insights into immune cell distribution and function.

3. Flow Cytometry (FC): This application helps in analyzing PD-L1 expression on the surface of immune cells, such as T cells, B cells, NK cells, and dendritic cells.

4. Functional Assays: The antibody is used in various in vivo functional assays to study the role of PD-L1 in immune regulation and disease models.

5. Disease Models: Clone 10F.9G2 is used in models of autoimmune diseases, such as diabetes, to accelerate disease progression by blocking PD-L1-mediated immune suppression.

6. Cancer Research: It is also used to study the role of PD-L1 in tumor immune evasion and to block PD-L1 interactions, which can transiently arrest tumor growth in mouse models of cancer.

The 10F.9G2 antibody is widely used in mouse models to target PD-L1 (CD274, B7-H1), often in combination with other antibodies or proteins that interrogate related immune checkpoint pathways or immune cell populations. The most commonly co-used antibodies and proteins in the literature are:

• PD-1 antibodies (e.g., 29F.1A12, RMP1-14): Used to block or detect the PD-1 receptor, another central checkpoint protein frequently studied with PD-L1 blockade.
• PD-L1 antibodies (e.g., MIH6, 10F.2H11): MIH6 is another anti-PD-L1 antibody, functionally similar to 10F.9G2 and often compared or sometimes co-used. The 10F.2H11 antibody is also frequently mentioned, as it specifically blocks PD-L1:B7-1 interactions, whereas 10F.9G2 blocks both PD-L1:PD-1 and PD-L1:B7-1.
• Isotype controls (e.g., Rat IgG2b): Used as negative controls alongside 10F.9G2 in functional assays to validate specificity.
• CD80 (B7-1) fusion proteins: Utilized to investigate the interaction between PD-L1 and CD80, since 10F.9G2 and 10F.2H11 have distinct blocking capacities for PD-L1:B7-1 interactions.
• Other immune cell markers/proteins: Antibodies against CD4, CD8, and sometimes dendritic cell, B cell, or NK cell markers are frequently used in multi-color flow cytometry or immunofluorescence panels with 10F.9G2 to analyze immune cell subsets expressing PD-L1.

Most common combinations in the literature:

• 10F.9G2 + PD-1 antibody (29F.1A12 or RMP1-14): For dual checkpoint inhibition studies.
• 10F.9G2 + MIH6 or 10F.2H11: For comparative studies of PD-L1 function/blockade.
• 10F.9G2 + isotype control: To confirm specificity and control experimental variability.
• 10F.9G2 + CD80 fusion protein: To dissect PD-L1–CD80 vs. PD-L1–PD-1 interactions.

Additional frequently used immune-related antibodies or proteins:

• CD3, CD4, CD8, CD45: To further phenotype T cell populations and immune infiltrates in conjunction with PD-L1 expression analysis.

In summary, the most frequently co-used antibodies or proteins with 10F.9G2 are other immune checkpoint antibodies (especially anti-PD-1, anti-CD80/B7-1, anti-PD-L1 clones such as MIH6, 10F.2H11), isotype controls, and immune cell markers relevant to the tissue/cell type being studied.

Clone 10F.9G2 is a rat monoclonal antibody targeting mouse PD-L1 (CD274, B7-H1) that has generated substantial scientific findings across multiple areas of cancer immunotherapy and autoimmune disease research. This antibody has become particularly valuable due to its unique dual-blocking capability and extensive validation in preclinical models.

Dual-Blocking Mechanism

The defining characteristic of 10F.9G2 is its ability to simultaneously block both major PD-L1-mediated immune checkpoint pathways. Specifically, it prevents the interaction between PD-L1 and PD-1, as well as between PD-L1 and B7-1 (CD80). This dual-blocking activity distinguishes it from other anti-PD-L1 antibodies like clone 10F.2H11, which only blocks the PD-L1:B7-1 interaction while leaving PD-L1:PD-1 binding intact. The two antibodies bind to distinct, non-overlapping epitopes on PD-L1, with 10F.9G2 sharing epitope similarity with another dual blocker, MIH5.

Radioimmunoconjugate Applications

Clone 10F.9G2 has proven highly effective when radiolabeled for imaging and targeted therapy applications. When conjugated with ^89^Zr, the antibody demonstrated excellent target specificity and binding to PD-L1-overexpressing CT26/PD-L1 mouse colon cancer cells compared to weakly expressing CT26 cells. PET imaging analysis revealed 3.9-fold greater accumulation in PD-L1-overexpressing tumors. Remarkably, gemcitabine co-treatment enhanced ^89^Zr-10F.9G2 binding to 145.4% of control levels in vitro, and increased tumor uptake from 1.56% to 6.24% of the injected dose per gram in CT26 tumor-bearing mice.

The F(ab')~2~ fragment of 10F.9G2, when radiolabeled with ^89^Zr, maintained target specificity in B16F10 murine melanoma cells while demonstrating earlier and higher tumor uptake than the full antibody—5.5 times greater at 2 hours post-injection in B16F10-bearing mice.

Comparative Efficacy in Tumor Models

Studies comparing 10F.9G2 with experimental PD-L1 vaccines have revealed important benchmarks for therapeutic efficacy. In BALB/c mice challenged with D2F2 and 4T1 tumor cell lines, the MVF-PD-L1(130) epitope vaccine and mAb 10F.9G2 both achieved significant tumor growth inhibition, with the vaccine showing slightly higher tumor growth inhibition (TGI) percentages in some models. However, both approaches significantly prolonged survival rates across multiple cancer models.

In three different syngeneic tumor models (CT26, D2F2, and 4T1), mice treated with TT3-PD-L1(130) vaccine demonstrated higher TGI percentages compared to 10F.9G2-treated mice, though both treatments substantially outperformed PBS controls and extended survival. These findings establish 10F.9G2 as a gold-standard comparator for evaluating novel PD-L1-targeting therapeutics.

Immunological Effects

The antibody elicits robust immune responses in treated animals, including increased T cell infiltration into target tissues such as pancreatic islets in diabetes models. In tumor contexts, 10F.9G2 treatment enhances cytokine production and delays tumor growth. These effects result from relieving PD-L1-mediated immunosuppression, thereby enabling more effective antitumor and autoimmune T cell responses.

Autoimmune Disease Research

Beyond oncology, 10F.9G2 has contributed significantly to understanding immune regulation in autoimmune diseases. Research using this antibody has demonstrated that the PD-L1:B7-1 pathway restrains diabetogenic effector T cells in vivo. By comparing 10F.9G2 (dual blocker) with 10F.2H11 (B7-1-specific blocker), researchers have been able to dissect the distinct contributions of each PD-L1 interaction pathway to immune homeostasis and disease pathogenesis.

The extensive citation of clone 10F.9G2 reflects its utility as a reliable tool for dissecting immune escape mechanisms, antitumor immunity, and autoimmune processes in mouse models, making it an essential reagent for preclinical immunotherapy research.

Dosing regimens of clone 10F.9G2, an anti-mouse PD-L1 antibody, generally vary from 100 to 250 µg per mouse per dose, administered intraperitoneally at a frequency of 2–3 times per week across most mouse models.

Key dosing details and how they may vary:

• Dose Range: Most studies and suppliers recommend 100–250 µg per mouse as a standard regimen. Some protocols report a fixed 200 µg dose in tumor models.
• Route: Intraperitoneal injection is consistently used across immune-oncology, infection, and depletion models.
• Frequency: Administration typically occurs 2–3 times weekly; regimens can be adapted based on experimental needs and model sensitivity.
• Dose Scaling: In more detailed pharmacokinetic studies, doses can be scaled by body weight, with 1–10 mg/kg reported (e.g., PK studies in CD1 mice), although this is less common in routine efficacy experiments and more relevant for PK/ADA analyses.
• Model Variability: Syngeneic tumor models (e.g., melanoma, MC38 colon carcinoma) and chronic infection studies mostly adhere to the standard range above, with occasional adjustment for mouse strain, tumor burden, or immune response intensity. Highly inflamed or resistant models may require more frequent dosing or closer monitoring due to variable antibody clearance and possible development of anti-drug antibodies (ADAs).
• Combination Therapy: Sometimes, dosing regimens are modified when 10F.9G2 is used in combination with other checkpoint inhibitors (e.g., anti-PD-1, anti-CTLA-4), but the base dose per injection remains similar.

Summary Table

Regimens are highly consistent across models; dose and frequency rarely differ unless dictated by specific study design requirements or observed pharmacokinetic changes (like ADA development).

In summary, clone 10F.9G2 is reliably dosed at 100–250 µg per mouse, 2–3 times weekly, intraperitoneally for most mouse models, with adjustments based on experimental context (such as strain or disease kinetics).