Armenian Hamster IgG Isotype Control F(ab’)2 fragment [Clone PIP] — Purified in vivo GOLD™ Functional Grade

Clone PIP is used in in vivo mouse studies primarily to investigate its role in breast cancer (BC) development, immune response, and metastasis. Researchers use genetically engineered breast cancer cell lines (such as 4T1 and E0771) that overexpress PIP, then transplant these cells into syngeneic (genetically matched) mouse models, typically BALB/c mice, to assess how PIP expression influences tumor growth, immune cell dynamics, and metastatic spread, particularly to the lungs.

Key details on in vivo use:

• Generation of PIP-expressing tumor cells: Mouse BC cell lines (e.g., 4T1, E0771) are transduced or transfected to stably express PIP.
• Transplantation into mice: These PIP-expressing cells are injected into mice, and compared to control cells (often empty vector, EV) to study the impact of PIP on tumor behavior.
• Assessment of tumor growth and immune response: Tumor onset and growth are monitored. Flow cytometry and immunological assays assess changes in immune cell types (NK cells, dendritic cells, Th2 cells) within tumors, revealing that PIP alters the antitumor immune microenvironment.
• Metastasis evaluation: At endpoint, organs (commonly lungs) are analyzed for metastatic colonies via clonogenic metastasis assays. PIP expression in 4T1 cells leads to increased metastasis to the lungs in both immunocompetent and immunodeficient mice.
• Use of PIP knockout mice: Separate studies also utilize mice genetically lacking PIP (PIP KO) to study effects on immune system development and response, finding impaired Th1 differentiation and altered signaling in immune cells.

Tools and reagents: For detection and mechanistic studies:

• PIP expression is monitored via Western blot and immunostaining.
• Antibodies against PIP (such as rabbit monoclonal anti-PIP, clone EP1582Y) are utilized to verify expression in cell and tissue samples.

In summary, clone PIP is engineered into tumor cell lines and introduced into mouse models to dissect its dual effects on antitumor immunity and metastasis, with findings assessed using immunological, histological, and molecular techniques.

Commonly used antibodies and proteins with PIP (phosphatidylinositol phosphates, often PIP1, PIP2, or PIP3) in the literature include other phosphoinositide-binding antibodies, phosphorylated proteins, signaling enzymes, and interacting partners relevant to lipid signaling and membrane dynamics.

Key antibodies and proteins commonly studied or co-detected with PIP include:

• Antibodies against other phosphoinositides:
  • Anti-PI(3)P, anti-PI(4)P, anti-PI(4,5)P2, and anti-PI(3,4,5)P3 monoclonal antibodies are frequently used to distinguish between different phosphorylated forms and localizations of phosphoinositides within cellular compartments.
  • Monoclonal antibodies like 4E10 (widely cited for HIV research) have shown cross-reactivity with both PIP and cardiolipin, indicating that panels of anti-phospholipid antibodies are often tested together.
• Proteins or domains with known PIP binding specificity:
  • Pleckstrin Homology (PH) domains, e.g., PHPLC?1, are routinely used as molecular probes for PIP2/PI(4,5)P2 in live-cell imaging, and overexpression of these probes is a common experimental strategy.
• Proteins involved in PIP metabolism or signaling:
  • PI kinases (e.g., PIPK? or phosphatidylinositol 4-phosphate 5-kinase ?) and phospholipases (such as PI-specific phospholipase C) are studied or inhibited alongside measurements of PIP and its downstream effects.
  • Proteins regulating vesicle trafficking, such as EEA1 (early endosome antigen 1, which binds PI3P), and others involved in endocytosis and exocytosis, are often monitored together.
• Other phospho-specific and membrane-interacting antibodies:
  • Anti-cardiolipin (CL), anti-cytokeratins, or antibodies for highly phosphorylated proteins like casein have been shown to cross-react or be used as controls in PIP-antibody assays.

If you are asking about PIP as "prolactin-induced protein" (also called GCDFP-15), common co-used antibodies in breast cancer or secretory studies may include:

• Markers for apoptosis and cell signaling: anti-CRADD, anti-DAPK1, anti-CD40.
• GCDFP-15 itself, especially in diagnostic pathology.

In summary, the most commonly used antibodies and proteins alongside PIP in the literature are those targeting other phosphoinositides (e.g., PI(3)P, PI(4,5)P2), PIP-binding domains/probes (especially PH domains), enzymes metabolizing PIP, and reference proteins involved in related signaling pathways. In cancer research or breast tissue studies, anti-apoptotic and signaling protein antibodies are frequent companions.

Key Findings from Clone PIP-Related Scientific Literature

PIP Plant Peptide Family

• Discovery and Classification: A recent study identified 128 PIP (encoding plant-derived peptides) genes across 23 plant species (10 monocots, 13 dicots) and classified them into two distinct clades, with Arabidopsis sequences AtPIP1 and AtPIP2 serving as representative members of each clade.
• Functional Divergence: AtPIP1 strongly inhibits root growth in Arabidopsis, whereas AtPIP2 is more effective at inducing immunity against pathogens. This functional dichotomy highlights the evolution of specialized roles within the PIP family.
• Role of SGP Motif: The SGP (Ser-Gly-Pro) motif, present (and sometimes duplicated) in PIP sequences, is important for their biological activity. Hydroxylation of the proline residue in the SGP motif enhances the function of PIP peptides, and similar modifications are observed in other plant peptide families. However, the exact molecular mechanism underlying the enhanced bioactivity after modification remains to be elucidated.
• Potential Applications: Exogenous application of PIP peptides, particularly AtPIP2, offers a potential strategy to enhance pathogen resistance in crops without causing significant root growth penalties, suggesting practical agricultural applications.
• Future Directions: The study emphasizes the need for in vivo experiments to confirm the effects of PIP peptides and their post-translational modifications in natural plant settings.

PIP-eco Genomic Pipeline in Microbiology

• Tool Development: PIP-eco is a bioinformatics pipeline designed for rapid and accurate identification of Escherichia coli pathotypes using whole-genome sequencing (WGS) data. It integrates local alignment, phylogenetic analysis, and Pathogenicity Island (PAI) analysis to assign pathotypes based on virulence factor markers.
• Performance and Accuracy: When tested on 400 E. coli genomes, PIP-eco assigned a pathotype to 70.9% of genomes and detected hybrid pathotypes in 3.4%. The pipeline demonstrated stable and reproducible performance across multiple test iterations.
• Hybrid Pathotype Detection: PIP-eco identified that hybrid pathotypes (especially those involving ExPEC/AIEC and STEC) are common, reflecting the dynamic evolutionary landscape and adaptability of pathogenic E. coli. The pipeline’s PAI analysis revealed that even within hybrid pathotypes, there is significant genomic diversity, with conservation of certain virulence genes suggesting functional constraints.
• Clinical Implications: The ability to accurately detect and classify hybrid pathotypes can enhance surveillance and inform clinical responses to emerging E. coli strains, which is crucial for public health.

Pip in Pseudomonas Phenazine Biosynthesis

• Gene Identification: In Pseudomonas chlororaphis PCL1391, the pip gene was identified as a novel activator of phenazine biosynthesis, specifically for phenazine-1-carboxamide (PCN), an antifungal metabolite.
• Mutant Analysis: A pip mutant strain failed to produce PCN, indicating that pip is essential for the biosynthesis of this secondary metabolite. The gene's role was confirmed through both transposon mutagenesis and complementation assays.
• Regulatory Mechanism: The study established that Pip acts as part of a regulatory network controlling the biosynthesis of PCN, which is important for the bacterium's ecological interactions and potential biocontrol applications.

Summary Table: Key Findings by PIP Context

Conclusion

The PIP acronym appears in diverse biological contexts, each with distinct scientific implications:

• In plants, PIPs are a multifunctional peptide family with roles in growth regulation and pathogen defense, modulated by specific peptide motifs and post-translational modifications.
• In microbiology, PIP-eco is a bioinformatic tool for precise classification of E. coli pathotypes, including detection of hybrids and analysis of virulence evolution.
• In bacterial secondary metabolism, pip is a regulatory gene essential for antifungal compound production in Pseudomonas.

These findings collectively demonstrate the versatility of the PIP nomenclature in biology, spanning peptide signaling, genomic analysis, and microbial metabolism.

Dosing regimens for clone PIP (commonly referring to piperacillin, especially in mouse models for mimicking human antibiotic exposure) vary according to the mouse model’s immune status, infection type, and study objectives, but are typically designed to simulate human pharmacokinetics and therapeutic exposures.

• In immune-competent and neutropenic mouse models, researchers use a human-simulated dosing regimen. Example: subcutaneous administration of piperacillin-tazobactam (TZP) at 500/62.5 mg/kg initially, followed by 100/12.5 mg/kg at 15 minutes, 200/25 mg/kg at 2.5 hours, and 75/9.375 mg/kg at 5 hours, repeated every 6 hours throughout the dosing period. This multi-step regimen replicates the plasma concentration-time profile seen in humans and is repeated over several days depending on the experimental infection window.

• These regimens are often tailored to the specific pharmacokinetic (PK) and pharmacodynamic (PD) goals of the study. For example, maintaining drug concentrations above the minimum inhibitory concentration (MIC) for the target organism (T>MIC) is prioritized when mimicking human exposures, which may require frequent dosing and variable amounts depending on metabolism, organism susceptibility, and the chosen administration route (usually subcutaneous or intraperitoneal).

• Dosing may also vary depending on the infection model: Some studies use different schedules or single high doses for acute infection, while chronic models may require repeated dosing at lower amounts.

• The choice of mouse strain, age, and disease model can influence the exact dosing, but the overall strategy is optimizing for comparable serum drug exposures to those achieved clinically.

Key considerations:

• Regimens are often more frequent and higher per body weight in mice than in humans, due to differences in metabolism and clearance.
• Determining the regimen involves PK/PD simulation and experimental validation for the specific mouse model and infection context.

If you are inquiring about a specific antibody clone named "PIP" rather than piperacillin/tazobactam, please clarify—the literature and results cited above focus on piperacillin-based antibiotic models, which are standard in preclinical mouse studies.