Anti-Mouse CD209b [Clone 22D1] — Purified in vivo GOLD™ Functional Grade

The clone 22D1 is a monoclonal antibody extensively used in in vivo mouse studies as a research tool for investigating CD209b (SIGN-R1) function and for targeting specific immune cell populations.

Primary Applications in In Vivo Studies

Immune Cell Targeting and DepletionClone 22D1 serves as a critical reagent for targeting marginal zone macrophages and lymph node medullary macrophages, which express CD209b on their surface. Researchers use this antibody to specifically identify and manipulate these immune cell populations during experimental procedures.

CD209b Functional BlockadeThe antibody has been reported to effectively block CD209b function in vivo. Since CD209b is involved in the innate immune response and binds to high-mannose-containing glycoproteins on microbial envelopes to initiate pathogen uptake, blocking this receptor with 22D1 allows researchers to study the consequences of disrupting this immune recognition pathway.

Technical Specifications for In Vivo Use

Antibody CharacteristicsClone 22D1 is an Armenian Hamster IgG antibody with a molecular weight of 150 kDa. It maintains high purity (>95%) and low endotoxin levels (<2EU/mg), making it suitable for in vivo applications where contamination could interfere with experimental results.

Dosing and AdministrationThe antibody is formulated in PBS at pH 7.0 without stabilizers or preservatives, and researchers can dilute it using specialized pH 7.0 dilution buffer for consistent in vivo delivery. The antibody solution should be stored at 4°C at stock concentration to maintain stability.

Research Context and Applications

Immunological StudiesResearchers utilize 22D1 in studies investigating innate immune responses, particularly focusing on how marginal zone macrophages contribute to pathogen recognition and clearance. The antibody's ability to block CD209b function makes it valuable for determining the specific role of this receptor in immune surveillance.

Flow Cytometry IntegrationBeyond in vivo blockade experiments, 22D1 is commonly used in flow cytometry applications to analyze CD209b expression patterns on different cell populations before and after in vivo treatments. This dual functionality allows researchers to both manipulate and monitor CD209b-expressing cells within the same experimental framework.

The clone 22D1 represents a specialized tool for dissecting the role of CD209b in mouse immune system function, providing researchers with both blocking capability and detection sensitivity necessary for comprehensive in vivo immunological studies.

The correct storage temperature for the sterile packaged clone 22D1 (Anti-mouse CD209b SIGN-R1 Antibody) is undiluted at 4°C and protected from prolonged exposure to light; do not freeze.

This guidance aligns with standard practices for antibody preservation, ensuring product stability and integrity:

• Store undiluted at 4°C.
• Protect from prolonged light exposure.
• Do not freeze.

Some suppliers note that as supplied, antibodies may alternatively be stored at -20°C to -70°C for up to 12 months, but for the specific product provided by BD (as per the cited datasheet), storage at 4°C (refrigerator temperature) is correct, and freezing is specifically discouraged.

If there are alternative formulations (e.g., lyophilized or diluted forms), storage conditions may differ. Always refer to the product datasheet or manufacturer instructions for the exact requirements of your batch.

The 22D1 antibody is primarily used to detect mouse CD209b (SIGN-R1), a marker of marginal zone and medullary macrophages. In the scientific literature, 22D1 is most often used in studies involving immune cell populations, particularly in combination with other antibodies and cell markers for immunophenotyping, flow cytometry, and immunohistochemistry.

Commonly co-used antibodies or proteins with 22D1 include:

• Macrophage and dendritic cell markers:
  • CD11b and F4/80: General markers for macrophages.
  • CD11c: Marker for dendritic cells.
• B cell and T cell markers:
  • B220 (CD45R): Marker for B lymphocytes, often used with CD209b to distinguish macrophages from B cells in spleen sections.
  • CD3, CD4, CD8: T cell markers for context in lymphoid tissue studies.
• Endothelial and stromal cell markers: For tissue context and exclusion strategies, such as CD31 (endothelial), ER-TR7 (stromal reticular).
• Isotype controls: Often an Armenian hamster IgG isotype control, matching the species and isotype of 22D1, is used to discriminate specific from nonspecific staining.
• Markers for functional or signaling molecules (occasionally):
  • MHC-II: For identifying antigen-presenting cells.
  • CD68: For lysosomal and phagocytic compartments within macrophages.

In immunofluorescence or flow cytometry panels, 22D1 is often included alongside these markers to distinguish SIGN-R1+ macrophages from other immune and non-immune cell types within the spleen, lymph nodes, or tissues of interest.

Additionally, peptide antibodies and conjugated secondary antibodies (such as fluorescent anti-Armenian hamster IgG) may also be used for detection and visualization, depending on the primary experimental platform.

No evidence suggests that 22D1 is typically used with TSC22D1 antibodies (despite the name similarity): TSC22D1 is an unrelated protein involved in transcriptional regulation.

Summary Table: Common Markers Used with 22D1

These combinations enable researchers to precisely characterize and separate SIGN-R1+ macrophages from other immune cell subsets for immunological and infectious disease research.

Based on the scientific literature, the key findings regarding TSC22D1 (clone 22D1) center around its role as a tumor suppressor protein with significant implications for cellular regulation and therapeutic applications.

Protein Family Structure and Variants

TSC22D1 belongs to a protein family that produces multiple variants from four different family genes. The most studied variants include TSC22D1-1, TSC-22 (TSC22D1-2), and TSC22(86) (TSC22D1-3), each with distinct characteristics and functions. TSC-22 itself is composed of 144 amino acids translated from a short variant mRNA of the TSC22D1 gene.

Cellular Functions and Biological Activities

The research reveals that TSC-22 induces differentiation, growth inhibition, and apoptosis in various cell types. This multifaceted role positions it as a crucial regulator of cellular homeostasis and makes it particularly relevant for cancer research and therapeutic development.

Subcellular Localization Patterns

Studies have identified distinct localization patterns for different TSC22D1 family proteins:

• TSC22D1-1 is predominantly localized in the nucleus
• TSC-22 (TSC22D1-2) is primarily found in the cytoplasm, particularly in mitochondria, but can translocate to the nucleus following DNA damage
• TSC22(86) (TSC22D1-3) demonstrates dual localization in both cytoplasm and nucleus

This differential localization suggests that each variant may have specialized cellular functions and regulatory mechanisms.

Protein Interactions and Binding Partners

Mass spectrometry analysis has identified several important binding proteins for TSC22D1 family members. Two key interactions have been validated:

Histone H1 Interaction: Both TSC-22 (TSC22D1-2) and TSC22(86) (TSC22D1-3) bind to histone H1 in the nucleus. This interaction may have significant implications for chromatin structure and gene expression regulation, as histone H1 is a linker histone that can both positively and negatively regulate transcription.

GNL3 Binding: Guanine nucleotide-binding protein-like 3 (GNL3), also known as nucleostemin, binds to TSC-22 (TSC22D1-2) in the nucleus. GNL3 interacts with p53 and MDM2, influencing cell cycle progression and cellular differentiation.

Proposed Molecular Mechanisms

The research suggests several potential mechanisms by which TSC22D1 family proteins exert their effects:

• Chromatin Regulation: TSC22D1 family proteins may promote histone H1 degradation, leading to chromatin binding replacement by HMGA2, which could alter expression of genes regulating cell proliferation, differentiation, apoptosis, and senescence
• Cell Cycle Control: Through interaction with GNL3, these proteins may influence cell cycle progression and inhibit proliferation in tumor cells

Therapeutic Implications

The findings position TSC22D1 family proteins as potential targets for molecular-targeted therapy and differentiation-inducing therapy. Their roles in promoting apoptosis, inhibiting growth, and inducing differentiation make them attractive candidates for cancer treatment strategies.

The research emphasizes that while multiple binding protein candidates have been identified, further investigation is needed to confirm these interactions under physiological conditions and to fully elucidate the functional significance of these protein-protein interactions in various cellular contexts.