Anti-Mouse CD48 (Clone HM48-1) – Purified in vivo PLATINUM™ Functional Grade

Clone HM48-1, an anti-mouse CD48 monoclonal antibody, has several well-documented in vivo applications in mice, primarily centered around modulating immune responses and studying CD48-mediated cellular interactions.

Blocking CD48-Mediated Interactions

The HM48-1 antibody effectively blocks the interactions between CD48 and its primary counter-receptors, CD2 and CD244, in living mice. This blocking capability makes it a valuable tool for investigating the role of these molecular interactions in immune cell function and communication. By preventing CD48 from binding to its natural ligands, researchers can assess the functional consequences of disrupting these pathways in whole animal systems.

Transplantation and Graft Survival Studies

One of the most significant in vivo applications is in transplantation research, where HM48-1 has been shown to prolong cardiac allograft survival. This application demonstrates the antibody's potential for studying immune tolerance mechanisms and developing strategies to prevent transplant rejection. The ability to extend graft survival by blocking CD48 interactions highlights the molecule's importance in the alloimmune response.

T Cell Modulation

HM48-1 provides costimulatory signals for T cells activated through their T cell receptor (TCR) in vitro, and this extends to in vivo applications where the antibody can modulate T cell responses. The antibody also inhibits the proliferative response of mitogen-activated spleen cells, making it useful for studying T cell activation and proliferation dynamics in living animals.

Inhibition of Cytotoxic Activity

The antibody has been reported to inhibit cytotoxic T lymphocyte (CTL) activity in vivo, which is particularly relevant for research involving cellular immune responses against tumors or infected cells.

These diverse applications make clone HM48-1 a versatile research tool for investigating immune regulation, cell-mediated immunity, and therapeutic interventions in mouse models of disease and transplantation.

Commonly used antibodies or proteins studied alongside HM48-1 (anti-mouse CD48) in the literature include those that target CD2 and CD244, as these are the primary ligands and interaction partners of CD48; researchers frequently block or analyze these pathways in tandem to study immune regulation and cell signaling.

Key companion antibodies/proteins appearing together with HM48-1:

• Anti-CD2 (e.g., clone 12-15): CD2 is a major receptor for CD48. Studies often use anti-CD2 antibodies, sometimes in combination with HM48-1, to dissect or block the CD48-CD2 interaction, for example to enhance effects such as prolongation of allograft survival and modulation of T cell activation.
• Anti-CD244 (2B4): CD244 is another principal receptor for CD48, especially relevant in studies involving NK cells and some T cell subsets.
• Anti-CD3 (e.g., CD3ε): Used for T cell activation assays, often in combination with HM48-1 to assess co-stimulation or inhibitory effects on T cell proliferation.
• Other leukocyte markers: Depending on the experiment, antibodies detecting surface markers such as CD4, CD8, CD19, or other immune cell lineage markers are frequently multiplexed with HM48-1 in flow cytometry panels for more detailed phenotyping (see product descriptions and application notes for common fluorochrome combinations and multicolor panels).

Usage context:

• In transplant and alloreactivity studies, anti-CD2 (clone 12-15) is often used with HM48-1 to more profoundly disrupt CD48 signaling, which results in synergistic prolongation of allograft survival.
• In basic immunology and signaling research, anti-CD244, anti-CD3, and lineage markers help to define which cells are affected by CD48 pathway blockade or modulation.

In summary, anti-CD2, anti-CD244, and general T/B cell phenotyping antibodies (e.g., anti-CD3, anti-CD4, anti-CD8, anti-CD19) are most commonly used in combination with HM48-1 in published research to interrogate CD48-related immune mechanisms.

The monoclonal antibody clone HM48-1 is primarily used to detect and study mouse CD48, a 45 kDa GPI-linked glycoprotein involved in immune cell activation, adhesion, and hematopoietic lineage differentiation. Key scientific findings from literature citations using clone HM48-1 include:

• CD48 Expression in Hematopoietic Progenitors: CD48 is differentially expressed among bone marrow hematopoietic progenitor subsets, making it a useful marker for distinguishing lineage commitment and predicting the primitiveness of stem cell populations. In mice:

  • HSCs (hematopoietic stem cells): CD150(+)CD244(-)CD48(-)
  • Multipotent progenitors (MPP): CD244(+)CD150(-)CD48(-)
  • Most restricted progenitors: CD48(+)CD244(+)CD150(-).

• Functional Studies: HM48-1 can modulate CD48 functions both in vitro and in vivo. Reported effects include:

  • Blocking CD48/CD2 and CD48/CD244 interactions, which are vital for T cell and NK cell activation.
  • Inhibiting proliferative responses of mitogen-activated spleen cells.
  • Providing costimulation for T cells activated via their T cell receptor (TCR).
  • Prolonging cardiac allograft survival in vivo by modulating immune responses.

• Immunophenotyping Utility: HM48-1 is extensively used in flow cytometry for the identification and sorting of immune cell populations, particularly to track CD48 expression on B cells, T cells, macrophages, and monocytes, and to study adhesion molecule function in immunology.

• Counter-receptors and Mechanism: CD2 and CD244 are the chief counter-receptors for CD48 in mice, and HM48-1 has been employed to disrupt these interactions for mechanistic studies.

• Methodological Notes: HM48-1 is validated for applications like flow cytometry and in vivo studies, often in mouse models of hematopoiesis, transplantation, and immunological function.

In summary, clone HM48-1 is foundational in mouse immunology for identifying hematopoietic subsets, dissecting the role of CD48 in immune activation and adhesion, and for functional blocking studies of CD48-mediated cell interactions. These findings are consistently cited in research on hematopoietic lineages, immune modulation, and transplant immunology.

Dosing regimens for clone HM48-1 (anti-mouse CD48 antibody) in mouse models typically vary by application, mouse strain, and experimental design, but published protocols provide relevant examples for both in vivo functional studies and flow cytometry.

Key dosing regimens across mouse models:

• In Vivo Functional Studies:

  • A frequently used regimen is 300 μg per dose, intraperitoneally (i.p.), administered at days -1 and 2 relative to the experimental induction. This schedule has been used to modulate immune cell populations and assess the antibody's impact on lymphocyte counts in mice.
  • In experimental autoimmune encephalomyelitis (EAE) models, anti-CD48 (clone HM48-1) was administered on days 4 and 7 post-immunization to affect CD4+ T cell proliferation and cytokine production. The exact dose for this regimen is not directly specified in that source but is generally consistent with published functional doses in the 200–300 μg per mouse range.

• Flow Cytometry (Ex Vivo Analysis):

  • For flow cytometric staining, the recommended dose is ≤ 0.25 μg per 1 × 10⁶ cells in 100 μl volume. Doses should be titrated depending on the specific cell type, conjugate, and detector sensitivity.
  • BALB/c splenocytes, for example, have been stained with the antibody per the manufacturer’s recommendation, confirming this range is standard for analytical applications.

Factors affecting dose selection:

• Mouse strain and disease model: Immunological responsiveness and baseline CD48 expression can vary, prompting dose adjustment for different strains or disease states.
• Route and timing of administration: Most in vivo studies use intraperitoneal injection, generally timed to coincide with or precede immunological challenge. For mechanistic studies, more frequent dosing or larger doses may be warranted to ensure blocking of CD48-mediated interactions.
• Reagent purity and endotoxin content: Highly sensitive studies (e.g., graft rejection, CTL inhibition) recommend purified, ultra-low endotoxin antibody preparations, and may adjust doses accordingly.

Summary Table: Dosing regimens of HM48-1 in mouse models

Additional notes:

• The precise dosing for other in vivo applications (e.g., blocking CD48-CD2 interaction) may differ and should be titrated based on pilot studies and published benchmarks for similar monoclonal antibodies.
• For analytical and blocking applications, manufacturers and published studies consistently advise trial titration to optimize signal and functional effect for the specific mouse strain and experimental condition.

In summary, while 300 μg i.p. per mouse is a common in vivo dose for HM48-1, analytical (flow cytometry) use requires much lower concentrations, and dosing may be tailored for different models and experimental objectives.