SPAC1952.17c Antibody

What is IL-17C and how does it differ from other IL-17 family members?

IL-17C is a secreted protein that shares the conserved cysteine-knot fold characteristic of the IL-17 family but shows considerable sequence divergence at the N-terminus. Unlike IL-17B which exists as a non-covalently linked dimer, IL-17C forms disulfide-linked dimers. Human IL-17C consists of 197 amino acid residues with a putative 18 amino acid signal peptide, sharing only 15-30% amino acid sequence identity with other IL-17 family members, making it structurally distinct . It primarily activates the receptor IL-17RE, which is preferentially expressed on Th17 cells and epithelial cells, distinguishing its signaling pathway from other IL-17 cytokines .

What are the primary tissue expression patterns of IL-17C?

IL-17C exhibits a highly restricted expression pattern compared to other IL-17 family members. It was initially detected as a rare expressed sequence tag (EST) in adult prostate and fetal kidney libraries . Unlike IL-17A and IL-17F which are predominantly produced by immune cells, IL-17C is primarily expressed by epithelial cells in response to pro-inflammatory cytokines (TNF-α and IL-1β) or microorganisms . This epithelial-specific expression suggests a distinct role in mucosal immunity and inflammatory responses compared to other IL-17 family cytokines.

How do IL-17C antibodies help characterize the functional properties of IL-17C?

IL-17C antibodies enable researchers to identify the pro-inflammatory functions of IL-17C, which include stimulating the release of TNF-alpha and IL-1 beta from monocytic cells (a property shared with IL-17B) . Through neutralization studies with anti-IL-17C antibodies, researchers have demonstrated that IL-17C activates both Th17/IL-17A responses and directly induces epithelial cell production of pro-inflammatory chemokines, cytokines, and antimicrobial peptides . This dual mechanism of action distinguishes IL-17C from other family members and highlights its unique role in mucosal defense and inflammation.

How can IL-17C antibodies be optimized for specific detection assays?

For optimal detection specificity in immunohistochemistry, researchers should perform heat-induced epitope retrieval (as demonstrated with VisUCyte Antigen Retrieval Reagent-Basic in the search results) before applying IL-17C antibodies. The recommended concentration for paraffin-embedded tissue sections is approximately 10 μg/ml with a 1-hour incubation at room temperature . For flow cytometry applications, intracellular staining requires fixation with paraformaldehyde and permeabilization with saponin to access cytoplasmic IL-17C. Always include appropriate isotype controls (such as MAB003) to confirm staining specificity and minimize background . Research laboratories should independently determine optimal antibody dilutions for each specific application and tissue type, as sensitivity can vary significantly between experimental systems.

What are the critical controls needed for IL-17C neutralization experiments?

When conducting IL-17C neutralization experiments, inclusion of appropriate control antibodies is essential. In the kidney injury model described in the research, normal IgG control antibody administered at equivalent doses (10 mg/kg) to the IL-17C neutralizing antibody was used as a control group . This control is crucial for distinguishing specific effects of IL-17C neutralization from non-specific antibody effects. Additionally, the timing of antibody administration represents a critical experimental parameter - the research demonstrated that delayed administration (3 hours post-injury) retained therapeutic efficacy, suggesting a clinically relevant treatment window . Researchers should also include measurements of IL-17C expression kinetics in their tissue of interest to determine optimal neutralization timing.

How can researchers distinguish between direct and indirect effects of IL-17C neutralization?

Distinguishing direct epithelial effects from Th17-mediated effects requires comprehensive experimental design. Researchers should assess multiple parameters including: 1) Changes in IL-17A expression and Th17 cell infiltration to evaluate indirect effects through the Th17 axis; 2) Direct measurement of epithelial cell-derived inflammatory mediators (MCP-1, IL-6, IL-1β); 3) Quantification of different inflammatory cell populations (macrophages, neutrophils) to assess downstream consequences . The research demonstrated that IL-17C blockade led to reduced IL-17A expression, decreased Th17 cell and macrophage infiltration, but had no effect on Treg cell infiltration, indicating selective immunomodulatory effects . Complementary in vitro studies with epithelial cell cultures can help isolate direct IL-17C effects from indirect immune-mediated effects.

What are the optimal techniques for detecting IL-17C in different tissue preparations?

Several validated techniques for IL-17C detection include:

For immunohistochemistry, cytoplasmic staining pattern in lymphocytes is characteristic of specific IL-17C detection . Flow cytometry requires appropriate gating strategies and comparison with isotype controls to ensure specificity, particularly when examining intracellular proteins .

What are the critical considerations for antibody preparation and storage?

Proper handling of IL-17C antibodies is essential for maintaining activity. According to the product information, researchers should use a manual defrost freezer and avoid repeated freeze-thaw cycles that can degrade antibody quality. The recommended storage durations are: 12 months from receipt date at -20 to -70°C in original supplied form; 1 month at 2 to 8°C under sterile conditions after reconstitution; or 6 months at -20 to -70°C under sterile conditions after reconstitution . For lyophilized antibodies, proper reconstitution is critical for maintaining activity. Small pack sizes may be supplied either lyophilized or as a 0.2 μm filtered solution in PBS, requiring different handling approaches .

How should researchers design in vivo IL-17C neutralization experiments?

Based on the kidney injury study, effective in vivo neutralization of IL-17C requires careful consideration of several factors:

• Dosage determination: The study used 10 mg/kg of IL-17C neutralizing antibody administered via tail vein injection

• Timing assessment: Expression kinetics showed IL-17C induction at 3 hours post-injury, peaking at 6 hours, guiding the 3-hour post-injury intervention timing

• Route of administration: Intravenous delivery via tail vein injection ensured rapid systemic distribution

• Outcome measurements: Multiple parameters including serum biomarkers (BUN, creatinine), tissue oxidative stress markers (MDA, SOD), histological assessment, inflammatory cytokine expression, and immune cell infiltration provided comprehensive evaluation

Researchers should conduct preliminary time-course experiments to determine the optimal intervention window specific to their disease model.

How can researchers address background staining issues when using IL-17C antibodies?

When encountering background staining issues in IL-17C detection, researchers should implement a systematic troubleshooting approach. First, ensure appropriate blocking steps are performed—the protocol for IL-17C detection in human Crohn's intestine utilized VisUCyte HRP Polymer Detection Reagents with specific blocking parameters . Second, include multiple controls: isotype control antibodies (as demonstrated with MAB003 in flow cytometry applications) and negative tissue controls lacking IL-17C expression . Third, optimize antibody concentration through titration experiments to find the concentration that maximizes specific signal while minimizing background. Finally, if background persists, consider alternative detection systems or more stringent washing procedures to remove non-specifically bound antibodies.

What are the potential confounding factors when interpreting IL-17C neutralization experiments?

Several confounding factors can complicate interpretation of IL-17C neutralization studies:

• Compensatory upregulation of other IL-17 family members

• Indirect effects on multiple inflammatory pathways beyond direct IL-17C signaling

• Timing-dependent effects that vary across disease progression stages

• Strain-dependent and sex-dependent variations in IL-17C responses

What is the therapeutic potential of IL-17C neutralization in inflammatory diseases?

Recent research demonstrates significant therapeutic potential for IL-17C neutralization in kidney diseases. In acute kidney injury models, post-ischemic IL-17C antibody administration (3 hours after injury) significantly attenuated elevation of blood urea nitrogen and serum creatinine, reduced malondialdehyde (MDA) levels, restored superoxide dismutase (SOD) activity, and improved histological parameters of tubular injury . In diabetic nephropathy models, IL-17C neutralization reduced albuminuria, ameliorated glomerular hypertrophy, and decreased expression of pro-inflammatory cytokines (MCP-1, IL-6, IL-1β) . These findings suggest therapeutic applications in both acute and chronic inflammatory kidney conditions, with potential relevance to other inflammatory diseases where IL-17C is implicated.

How do IL-17C responses differ between acute and chronic inflammatory conditions?

Research comparing acute kidney injury and diabetic nephropathy models revealed important differences in IL-17C-mediated inflammatory responses:

These differences suggest context-dependent roles for IL-17C in neutrophil recruitment depending on the acute versus chronic nature of inflammation . Researchers investigating IL-17C should consider these temporal dynamics when designing studies and interpreting results across different disease models.