ch25h Antibody

What is CH25H and what biological functions does it serve?

CH25H (Cholesterol 25-hydroxylase) is a key enzyme that catalyzes the conversion of cholesterol to 25-hydroxycholesterol (25OHC). This enzyme plays critical roles in cholesterol metabolism and immune regulation. The 25OHC metabolite produced by CH25H functions as a potent modulator of immune responses and inflammatory processes . CH25H has a calculated molecular weight of approximately 32 kDa and consists of 272 amino acids based on its sequence data . Research has identified CH25H as a metabolic switch that constrains T cell effector expansion in tissues through its metabolite 25OHC, highlighting its importance in immune homeostasis .

What detection applications are CH25H antibodies validated for?

CH25H antibodies have been validated for multiple research applications:

These applications allow researchers to detect CH25H protein expression in various experimental contexts, including visualization in tissue sections and quantification in cell lysates .

What species reactivity do commercial CH25H antibodies demonstrate?

Different CH25H antibodies exhibit varied species reactivity profiles:

When selecting an antibody for your research, it's important to verify the species compatibility with your experimental model .

What positive controls are recommended for CH25H antibody validation?

For effective validation of CH25H antibodies, specific positive controls have been documented:

• For immunohistochemistry: Human kidney tissues have been used successfully as positive controls

• For immunoprecipitation: Mouse liver tissue shows detectable CH25H expression

• For Western blot: A band at approximately 31.7 kDa should be expected in appropriate tissue lysates

Using these established positive controls ensures proper validation of antibody specificity and experimental protocols .

What are the optimal storage and handling conditions for CH25H antibodies?

To maintain antibody integrity and performance, the following storage and handling protocols are recommended:

• Store vials at -20°C prior to opening

• For extended storage, aliquot contents and freeze at -20°C or below

• Avoid repeated freeze-thaw cycles

• Centrifuge product if not completely clear after standing at room temperature

• Most CH25H antibodies remain stable for several weeks at 4°C as undiluted liquid

• Dilute only immediately before use

These practices help preserve antibody activity and prevent degradation that could compromise experimental results .

What buffer systems are used in commercial CH25H antibody preparations?

Different manufacturers employ specific buffer formulations to maintain antibody stability:

Understanding buffer composition is important when designing experiments, especially when combining antibodies with other reagents or determining compatibility with specific applications .

What antigen retrieval methods are recommended for CH25H immunohistochemistry?

For optimal antigen detection in IHC applications using CH25H antibodies, specific antigen retrieval protocols have been recommended:

• TE buffer (pH 9.0) is suggested as the primary antigen retrieval solution for Proteintech's CH25H antibody

• Alternatively, citrate buffer (pH 6.0) may be used if TE buffer produces suboptimal results

• The specific antigen retrieval protocol should be optimized for each tissue type and fixation method

Proper antigen retrieval is critical for exposing epitopes that may be masked during fixation processes, thereby improving antibody binding and signal intensity .

How is CH25H expression regulated in immune cells?

Research has revealed complex regulatory mechanisms controlling CH25H expression:

• IL-27 is a potent inducer of CH25H expression in CD4+ T cells, more effective than type I interferons

• The combination of IL-27 and TGF-β significantly up-regulates CH25H protein expression

• CH25H expression is selectively inducible in CD4+ T cells but not in CD8+ T cells

• The induction of CH25H expression in T cells occurs in a STAT1-dependent manner

• Memory CD4+ T cells can also up-regulate CH25H when stimulated via TCR crosslinking with IL-27

These regulatory pathways highlight the specific contexts in which CH25H is expressed during immune responses, suggesting targeted research approaches .

What is the relationship between T-bet and CH25H expression?

An important regulatory relationship exists between the transcription factor T-bet and CH25H:

• T-bet functions as a negative regulator of CH25H expression

• In Tbx21−/− (T-bet knockout) CD4+ T cells, CH25H expression is significantly up-regulated compared to wild-type cells after IL-27 stimulation

• Tbx21−/− T cells produce more 25OHC upon IL-27 stimulation than wild-type T cells

• IFN-γ, which induces T-bet in TH1 cells, fails to induce CH25H expression in wild-type T cells

• In the absence of T-bet, IFN-γ significantly up-regulates CH25H expression

This regulatory mechanism provides insight into how T cell differentiation programs may control CH25H-mediated immune modulation .

How does 25OHC production via CH25H affect T cell functions?

The CH25H enzymatic product 25OHC has significant effects on T cell biology:

• Activated CD4+ T cells produce minimal 25OHC under standard conditions

• IL-27 stimulation promotes approximately sevenfold induction of 25OHC production

• The combination of IL-27 and TGF-β causes massive increase in 25OHC production

• CH25H-deficient CD4+ T cells are unable to produce 25OHC even when treated with cytokine combinations

• 25OHC functions as a metabolic switch that constrains excessive bystander T effector expansion in tissues

• 25OHC down-regulates gene expression of cholesterol biosynthetic enzymes

These findings highlight how CH25H-mediated production of 25OHC serves as an immunoregulatory mechanism affecting T cell responses .

What experimental approaches can detect CH25H protein localization in cells?

Several methods have been validated for visualizing CH25H protein localization:

• Immunofluorescence staining can confirm CH25H protein up-regulation after cytokine treatment

• In unstimulated cells, CH25H protein is typically undetectable by immunofluorescence

• Immunohistochemistry of paraffin-embedded tissues, such as human colon cancer samples, can reveal CH25H expression patterns

• For subcellular localization studies, confocal microscopy combined with organelle-specific markers may be required

These approaches provide spatial information about CH25H expression, complementing biochemical and molecular analyses .

What disease models are appropriate for studying CH25H function?

Based on its implicated roles in pathology, several disease models are suitable for investigating CH25H function:

• Atherosclerosis models: CH25H dysregulation has been implicated in atherosclerotic processes

• Multiple sclerosis models: CH25H may play roles in neuroinflammation and demyelination

• Viral infection models: CH25H and 25OHC have been shown to modulate antiviral responses

• Inflammatory disorders: CH25H's role in immune regulation makes it relevant to various inflammatory conditions

These disease models provide contexts for studying the physiological and pathological roles of CH25H and potential therapeutic interventions targeting this pathway .

How can researchers troubleshoot non-specific binding with CH25H antibodies?

When encountering non-specific binding issues with CH25H antibodies, consider these troubleshooting strategies:

• Increase antibody dilution (start with manufacturer's recommended range and titrate further if necessary)

• Extend blocking time using 5% BSA or serum from the same species as the secondary antibody

• Add 0.1-0.5% Triton X-100 in blocking buffer to reduce non-specific hydrophobic interactions

• Perform additional washing steps using PBS with 0.05-0.1% Tween-20

• Verify specificity using appropriate positive and negative controls, including CH25H knockout tissues if available

Non-specific binding can compromise data interpretation, making proper optimization critical for reliable results .

What is the temporal expression profile of CH25H in stimulated T cells?

Understanding the temporal dynamics of CH25H expression is important for experimental design:

• CH25H expression in CD4+ T cells peaks at 24-48 hours after IL-27 stimulation

• By day 3, CH25H mRNA expression typically diminishes

• Protein expression may persist longer than mRNA expression

• The timing of CH25H induction varies depending on the specific stimuli and cell types

These temporal aspects should inform sampling timepoints when designing experiments to study CH25H expression or function .

How can epigenetic regulation of CH25H expression be analyzed?

For researchers interested in the epigenetic control of CH25H expression:

• ChIP-seq analysis for histone marks (particularly H3K4me1 and H3K27ac) can identify enhancer regions

• Enhancer marks have been detected downstream of the CH25H gene in wild-type cells

• T-bet binding sites can be identified through ChIP-seq approaches

• DNA methylation analysis of the CH25H promoter may provide additional regulatory insights

• ATAC-seq can reveal chromatin accessibility changes at the CH25H locus under different conditions

These approaches can uncover the epigenetic landscape controlling CH25H expression in different cellular contexts .

How might CH25H antibodies contribute to cancer research?

CH25H antibodies have applications in cancer research contexts:

• Immunohistochemistry of paraffin-embedded human colon cancer samples has been performed to assess CH25H expression

• Changes in cholesterol metabolism are known to affect cancer cell proliferation and survival

• 25OHC produced by CH25H may influence tumor microenvironment and immune cell infiltration

• Altered CH25H expression patterns could serve as potential biomarkers in certain cancer types

• The regulatory role of CH25H in inflammation may be relevant to inflammation-associated cancers

These research directions highlight the potential significance of CH25H beyond its established roles in immune regulation .

What methodological considerations are important when quantifying 25OHC production?

For accurate quantification of the CH25H product 25OHC:

• Gas chromatography-mass spectrometry (GC-MS) analysis is the gold standard for precise 25OHC measurement

• Liquid chromatography-mass spectrometry (LC-MS) can also be employed with appropriate standards

• Sample preparation requires careful lipid extraction procedures to preserve oxysterol integrity

• Internal standards should be used to account for extraction efficiency and instrument variation

• CH25H-deficient cells serve as essential negative controls to confirm specificity of detected 25OHC

These methodological considerations ensure reliable quantification of 25OHC when studying CH25H enzymatic activity .