Anti-Mouse CD8b.2 [Clone 53-5.8] — Purified in vivo PLATINUM™ Functional Grade

Clone 53-5.8 is a monoclonal rat IgG1 antibody specific for the mouse CD8? (Lyt 3.2) chain, and in in vivo mouse studies, it is widely used for the selective depletion of CD8? T cells. This depletion allows researchers to assess the functional roles of CD8? T cells in immune responses without affecting other cell populations such as CD8? dendritic cells.

Key uses in in vivo mouse studies:

• CD8? T cell depletion: Administration of anti-CD8? (clone 53-5.8) depletes CD8? T lymphocytes efficiently and specifically in vivo, but does not significantly deplete CD8? CD11c? dendritic cells or other non-T cell populations.
• Investigation of immune function: Depleting CD8? T cells with this clone is a standard approach in immunological research to study the roles of cytotoxic T lymphocytes (CTLs) in processes such as viral infection, tumor immunity, autoimmunity, and transplant rejection.
• Advantage over anti-CD8? clones: While both anti-CD8? and anti-CD8? antibodies are used for T cell depletion, clone 53-5.8 targets only CD8?, providing greater specificity for mature CD8? T cells, as some non-T cell populations express CD8? but not CD8?.

Experimental notes:

• The antibody is typically administered intraperitoneally or intravenously to mice, and various suppliers offer guidance regarding dosage and schedules based on experimental needs.
• Clone 53-5.8 is routinely validated by flow cytometry, but its primary in vivo use is for cell depletion.
• It is most effective in mouse strains expressing Ly-3.2 (most common laboratory strains), but has weak reactivity with Ly-3.1 strains, so strain compatibility must be checked.

Summary Table:

Limitations:

• Not effective in mouse strains expressing only Ly-3.1 alleles.
• Not used for general flow cytometry staining protocols; better suited for depletion purposes, though can be validated for flow.

Related clones: For broader CD8 depletion, anti-CD8? (e.g., clone 53-6.72) can be used, but may affect additional cell types.

In summary: Clone 53-5.8 is an established tool for the specific in vivo depletion of CD8? T cells in mice, enabling precise dissection of T cell–mediated immune mechanisms in experimental models.

Commonly used antibodies or proteins alongside 53-5.8 (anti-mouse CD8?) include other markers for T cell subsets, cytotoxic cell depletion, and core immune characterization: frequently used companions are anti-CD8? (clone 53-6.7 or 53-6.72), anti-CD3, anti-CD4, and pan-leukocyte antibodies such as anti-CD45.

Details and Context:

• Anti-CD8? (53-6.7 or 53-6.72): The most common pairing in the literature is with anti-CD8?. 53-5.8 targets the CD8? chain, while anti-CD8? targets the CD8? chain. Because CD8 exists as a heterodimer (CD8??) or homodimer (CD8??), both antibodies are often used together to distinguish between these populations. For instance, depletion or phenotyping experiments typically use both to accurately dissect CD8+ T cell subsets.

• Anti-CD3: Used to identify total T cells, anti-CD3 is commonly employed in panels with CD8?-specific and CD8?-specific antibodies for T cell immunophenotyping and depletion studies.

• Anti-CD4: Included for comprehensive T cell subset analysis to distinguish CD8+ from CD4+ T cells, allowing for a full assessment of cytotoxic and helper T cell populations.

• Anti-CD45: As a pan-leukocyte marker, anti-CD45 is included in panels to identify all leukocytes, often in flow cytometry settings.

• Markers for dendritic cells and other immune cells: Since CD8 can also be expressed on dendritic cells and some NK cells, researchers often include additional markers like anti-CD11c (dendritic marker), anti-NK1.1 (NK marker), and viability dyes to unambiguously define subpopulations.

Summary Table: Common Co-Used Antibodies/Proteins

Other Notes:

• In depletion experiments, research highlights the parallel use of both 53-5.8 (CD8?) and 53-6.7/53-6.72 (CD8?) to study effects on different CD8+ subsets and the specific roles of each.
• When used in vivo for depleting CD8+ T cells, 53-5.8 is often selected because it depletes CD8+ T cells efficiently but not CD8+ dendritic cells, whereas CD8? reagents deplete both.

These standard antibody panels are widely used in immunological studies involving cytotoxic T cells, especially in murine models.

Key findings from scientific citations of clone 53-5.8 center on its use as an anti-mouse CD8? monoclonal antibody for depletion or detection of CD8+ T cells, revealing significant functional and biological consequences in immunological studies.

• Depletion Effectiveness: Clone 53-5.8 is more effective at depleting mouse CD8+ T cells compared to antibodies targeting CD8? (such as clone 53-6.7). Attempts to combine lower doses of both antibodies do not improve depletion efficiency over clone 53-5.8 alone.

• Surviving CD8+ T Cell Population:

  • CD8+ T cells surviving depletion by clone 53-5.8 show altered differentiation and homing marker profiles and localize differently within the spleen compared to survivors of anti-CD8? treatment or untreated controls.
  • Surviving cells exhibit increased cytotoxic function compared to those depleted with anti-CD8?, indicating possible enhancement in immune effector activity after treatment.
  • Flow cytometric detection may underestimate surviving CD8+ T cells, as CD8 is internalized and downregulated after treatment with clone 53-5.8, requiring careful gating strategies.

• Disease Model Findings:

  • In Plasmodium berghei infection models, administration of clone 53-5.8 depletes CD8+ T cells, significantly reducing pulmonary vascular leakage and protecting against experimental cerebral malaria, without affecting parasitemia levels.
  • These findings confirm the pathogenic role of CD8+ T cells in tissue injury during certain infections and demonstrate the utility of clone 53-5.8 in dissecting immune cell contributions.

• Technical Usage:

  • Clone 53-5.8 specifically binds the ? chain of the mouse CD8 differentiation antigen, making it suitable for both depletion and detection of CD8+ T cells in various mouse strains.
  • It is commonly used in immunotherapy, adoptive transfer, and T cell depletion protocols.

Summary Table: Key Effects of Clone 53-5.8 (Anti-CD8? mAb) in Scientific Literature

Thus, clone 53-5.8 is a central tool for CD8+ T cell depletion and detection, with implications for immune function, experimental interpretation, and disease model outcomes.

Dosing regimens for clone 53-5.8 (anti-mouse CD8?) in mouse models typically involve 5 mg/kg administered intraperitoneally; the exact schedule varies depending on the experimental design, but a common regimen is dosing on the day before, the day of, and then weekly after tumor or disease initiation. The specific timing and frequency may be adjusted based on the disease model and study goals.

Supporting details:

• In a tumor model study (CT26, MC38, B16-F10 lines), 53-5.8 was administered at 5 mg/kg i.p.: on the day before, the day of tumor cell implantation, and then weekly thereafter for sustained CD8+ T cell depletion.
• Most protocols use intraperitoneal (i.p.) injection, with some studies reporting complete depletion of CD8+ T cells, but not of CD8+CD11c+ dendritic cells, under these regimens.
• Vendors and general antibody dosing guides note that for similar CD8 depleting antibodies, typical doses range from 200–250 ?g per mouse (about 8–10 mg/kg for a 20–25g mouse), given 2–3 times per week, but clone 53-5.8-specific published studies often use the 5 mg/kg schedule.
• The precise regimen can vary by context:
  • Tumor immunology studies may initiate dosing pre- and peri-tumor cell introduction.
  • Chronic disease or infection models may extend or alter the schedule for ongoing depletion.

Key points on variability:

• Model specificity: Some protocols tailor the regimen based on model (e.g., CT26 vs. MC38 vs. B16-F10), but the core dosing schedule—initial depletion around disease induction with maintenance dosing weekly—remains consistent.
• Study endpoint and duration: The duration (2–3 weeks vs. longer) and escalation (monotherapy or in combination) may influence how often and how long the antibody is dosed.

In summary, clone 53-5.8 is most often dosed at 5 mg/kg i.p., starting shortly before or at disease initiation, and then weekly thereafter, with minor adjustments based on mouse strain, tumor type, or the duration of experimental endpoints. If using other CD8 depleting antibodies, dosing schedules and quantities may differ slightly.