ATP19 Antibody

What is ATP19 Antibody and what cellular components does it target?

ATP19 Antibody is a monoclonal antibody that targets adenosine triphosphate synthase (ATP synthase), a critical enzyme complex involved in cellular energy production. ATP synthase is primarily located in the inner mitochondrial membrane but has been identified ectopically on the cell surface of various cancer cells. This ectopic expression makes ATP synthase an important target for cancer diagnostics and therapeutics. The antibody binds specifically to ATP synthase components, allowing for detection and potential therapeutic targeting of cells with aberrant ATP synthase expression .

How is ATP19 Antibody typically produced for research applications?

ATP19 Antibody is typically produced using hybridoma technology, where antibody-producing B cells from immunized animals are fused with myeloma cells to create stable cell lines that continuously produce the desired monoclonal antibody. For research applications, these antibodies are purified using affinity chromatography and can be stored as aliquots at -78°C to maintain their binding efficacy . The molecular weight of commonly used anti-ATP synthase antibodies is approximately 52 kDa, consistent with standard IgG antibody structures .

What are the primary applications of ATP19 Antibody in basic research?

In basic research, ATP19 Antibody serves several crucial functions:

• Identification and characterization of ATP synthase expression in different cell types

• Investigation of energy metabolism in normal and pathological states

• Study of mitochondrial function and dysfunction

• Analysis of cellular responses to metabolic stress

• Detection of ectopic ATP synthase as a biomarker in various disease models

• Flow cytometry-based identification of cellular populations with distinct metabolic profiles

What are the optimal methods for radioiodination of ATP19 Antibody for imaging studies?

The Iodogen tube method has proven effective for radioiodination of anti-ATP synthase antibodies. The protocol involves:

• Incubating 40 μg (range: 5-80 μg) of anti-ATP synthase monoclonal antibody with 185 MBq of 125I or 131I in phosphate-buffered saline (pH 7.4) in an Iodogen-precoated tube (50 μg)

• Maintaining the reaction for 25 minutes at room temperature

• Purifying the radiolabeled antibody by gel filtration on a PD-10 column

• Eluting with PBS

• Collecting and combining the 2-3 fractions with highest radioactivity

This approach yields radiolabeled antibodies suitable for both diagnostic imaging (using 125I) and therapeutic applications (using 131I), making it valuable for theragnostic approaches in cancer research .

How should flow cytometry panels be designed to incorporate ATP19 Antibody with other cellular markers?

When designing multiparameter flow cytometry panels that include ATP19 Antibody, researchers should consider:

• Selection of compatible fluorophores based on the excitation/emission properties of your flow cytometer

• Inclusion of appropriate lineage markers to identify specific cell populations

• Addition of functional markers to assess cellular activation state

• Incorporation of viability dyes to exclude dead cells

For example, when analyzing T cell subsets alongside metabolic markers like ATP synthase, researchers can develop panels similar to the one shown below:

This design allows simultaneous assessment of ATP synthase expression across different T cell subpopulations, enabling correlation between metabolic profiles and immune cell function .

How effective is radiolabeled ATP19 Antibody for cancer imaging and biodistribution studies?

Radiolabeled anti-ATP synthase antibodies have demonstrated significant potential for cancer imaging applications. In biodistribution studies using 125I-ATPS mAb in MKN-45 tumor-bearing mice, researchers observed:

• Peak xenograft uptake at 24 hours post-intravenous injection

• Optimal tumor-to-background contrast at 48 hours post-injection

• Specific accumulation in tumors with high ATP synthase expression

These characteristics make radiolabeled anti-ATP synthase antibodies promising candidates for cancer detection, particularly in gastric cancer models like MKN-45 where they show high specificity. The prolonged retention in tumor tissues provides a substantial window for imaging procedures, enhancing the clinical utility of these antibodies as diagnostic tools .

What is the evidence for ATP19 Antibody efficacy in radioimmunotherapy applications?

Studies have demonstrated that 131I-labeled anti-ATP synthase monoclonal antibodies significantly suppress tumor growth in preclinical models. In experiments with MKN-45 tumor-bearing mice, treatment with 18.5 MBq 131I-ATPS mAb showed:

• Significant reduction in tumor volume compared to control groups treated with isotype IgG or vehicle

• Measurable tumor growth inhibition (TGI) within weeks of treatment initiation

• Sustained anti-tumor effects through the targeting of ectopic ATP synthase on cancer cells

This approach represents an alternative to traditional angiostatin therapy, which requires daily injections and faces production challenges. By targeting ATP synthase (identified as the receptor for angiostatin), 131I-ATPS mAb provides a more practical approach to inhibiting tumor angiogenesis while simultaneously delivering therapeutic radiation to tumor cells .

What are common challenges in ATP19 Antibody specificity validation and how can they be addressed?

Researchers frequently encounter several challenges when validating the specificity of anti-ATP synthase antibodies:

• Cross-reactivity with similar proteins: ATP synthase shares structural similarities with other ATPases. To address this, perform comprehensive blocking experiments with recombinant ATP synthase proteins and assess binding to knockout cell lines.

• Distinguishing between mitochondrial and ectopic ATP synthase: Use cell fractionation techniques to separate membrane and mitochondrial fractions, followed by Western blotting to confirm target location.

• Variable expression levels across cell types: Test antibody performance across multiple cell lines with known ATP synthase expression levels to establish detection thresholds.

• Background in immunohistochemistry applications: Optimize blocking protocols using bovine serum albumin (1-5%) and include appropriate isotype controls in parallel experiments.

For definitive validation, a combination of techniques including Western blotting, immunoprecipitation, flow cytometry, and immunofluorescence microscopy should be employed with appropriate positive and negative controls.

How can researchers optimize uptake studies with radiolabeled ATP19 Antibody?

To optimize uptake studies using radiolabeled anti-ATP synthase antibodies, researchers should:

• Screen multiple cancer cell lines: Test uptake across diverse cancer cell types to identify those with highest specificity, as demonstrated in studies where MKN-45 cells showed superior uptake compared to other cancer cell lines .

• Optimize antibody concentration: Titrate antibody concentrations (typically in the range of 5-80 μg) to determine the optimal amount for specific binding while minimizing non-specific uptake .

• Consider time-dependent kinetics: Establish a time course for uptake studies, noting that peak tumor uptake may occur at 24 hours post-injection, while optimal tumor-to-background contrast might require 48 hours .

• Implement competitive binding assays: Include unlabeled antibody as a competitor to confirm specificity of radiolabeled antibody binding.

• Standardize quantification methods: Use consistent methods such as gamma counting for quantification, and express results as percentage of injected dose per gram of tissue (%ID/g) for reliable comparisons between experiments.

How can ATP19 Antibody be incorporated into bispecific antibody designs for enhanced therapeutic potential?

Advanced research applications increasingly focus on integrating anti-ATP synthase antibodies into bispecific antibody (BsAb) formats to enhance therapeutic efficacy. Researchers can:

• Utilize single-chain fragment variable (scFv) domains derived from anti-ATP synthase antibodies combined with anti-CD3 scFvs to create bispecific T cell engagers (BiTEs) .

• Implement high-throughput screening platforms to identify optimal bispecific configurations, which can screen up to 1.5 million variant library cells per run and isolate functional clones even at low abundance (0.008%) .

• Design formats that combine ATP synthase targeting with immune effector recruitment, allowing simultaneous targeting of cancer metabolism and activation of anti-tumor immunity.

• Evaluate various linker lengths and compositions to optimize the spatial configuration of the binding domains, which significantly impacts functional efficacy of the bispecific constructs.

This approach leverages the specificity of anti-ATP synthase antibodies for cancer cells while recruiting T cells to the tumor microenvironment, potentially enhancing therapeutic outcomes beyond those achieved with monospecific antibodies .

What are the considerations for developing ATP19 Antibody-drug conjugates (ADCs)?

Developing antibody-drug conjugates using anti-ATP synthase antibodies requires careful consideration of several factors:

• Selection of appropriate cytotoxic payloads: Based on the cancer type and intracellular processing of the ATP synthase-antibody complex, researchers must select payloads with suitable mechanisms of action (DNA-damaging agents, microtubule inhibitors, etc.).

• Optimization of drug-to-antibody ratio (DAR): Determine the optimal number of drug molecules per antibody (typically 2-4) to balance potency with pharmacokinetic properties.

• Linker chemistry selection: Choose between cleavable linkers (sensitive to pH, proteases, or reducing environments) and non-cleavable linkers based on the internalization and processing kinetics of the ATP19 Antibody.

• Characterization of internalization kinetics: Assess the rate and efficiency of antibody internalization after binding to cell-surface ATP synthase to ensure efficient delivery of the cytotoxic payload.

• Evaluation of bystander effects: Consider whether the released drug can diffuse to neighboring cells, which may be advantageous for heterogeneous tumors but could increase off-target toxicity.

The development process should include rigorous in vitro characterization of binding, internalization, and cytotoxicity, followed by in vivo studies addressing pharmacokinetics, biodistribution, and therapeutic efficacy.

How might ATP19 Antibody contribute to understanding the relationship between cellular metabolism and immune function?

Recent advances suggest potential applications of anti-ATP synthase antibodies in understanding the interplay between metabolism and immunity:

• Metabolic profiling of immune cell subsets: Anti-ATP synthase antibodies can be incorporated into multiparameter flow cytometry panels to characterize the metabolic states of different immune cell populations, particularly T cell subsets including regulatory T cells, Th2 cells, and effector T cells .

• Investigation of metabolic reprogramming during immune responses: By tracking ATP synthase expression and localization during immune cell activation, researchers can gain insights into how metabolic shifts support functional changes in immune cells.

• Analysis of energy metabolism in the tumor microenvironment: Anti-ATP synthase antibodies enable the study of metabolic competition between tumor cells and infiltrating immune cells, potentially revealing new therapeutic targets.

• Correlation of ATP synthase expression with immune checkpoint molecules: Combined analysis of ATP synthase and immune checkpoint receptors may uncover novel relationships between cellular metabolism and immune suppression mechanisms.

This research direction bridges two traditionally separate fields—cancer metabolism and tumor immunology—potentially leading to integrated therapeutic approaches that target both metabolic vulnerabilities and immune evasion mechanisms.