Anti-Mouse CD28 [Clone E18] — Purified in vivo GOLD™ Functional Grade

Clone E18 is a monoclonal antibody against murine CD28, commonly used in mice for in vivo modulation of T cell activation, particularly as a co-stimulatory signal for T cell functional assays, and has also been applied therapeutically in disease models such as myocardial infarction.

Main in vivo applications of clone E18 in mice:

• T cell activation and costimulation: E18 can stimulate murine T lymphocytes in combination with anti-CD3 antibody, mimicking physiological costimulation required for robust T cell responses.
• Blocking ligand binding: E18 has been used to block ligand binding to CD28, modulating immune responses and costimulatory pathways in vivo.
• Therapeutic disease models: In mouse models of myocardial infarction, E18 treatment improved survival and reduced adverse cardiac events, indicating immunomodulatory and protective effects during tissue injury.
• Functional assays: E18 is used for functional studies examining T cell proliferation, cytokine production, and other immune outcomes following CD28 engagement.

Supporting details:

• E18 specifically recognizes murine CD28, a co-stimulatory receptor expressed on T cells, and can be used for both flow cytometry and functional in vivo assays.
• It can be administered to mice in experimental protocols to study T cell-driven immune responses, including autoimmunity, infection, and tissue injury contexts.
• While E18 has been verified for costimulation and blocking activity, it is important to distinguish its mode of action from CD28 “superagonist” antibodies (like D665).

Additional Notes:

• Product datasheets recommend using E18 diluted appropriately for in vivo applications, and ensure storage requirements to maintain antibody stability.
• Not all anti-CD28 antibodies are suitable for in vivo work—E18 is explicitly described for T cell modulation and blocking studies, while other clones may function differently or be reserved for ex vivo/flow cytometry purposes.

Overall, clone E18 is widely used for research targeting T cell costimulatory pathways, immune modulation, and therapeutic intervention in mouse disease models.

Commonly used antibodies or proteins paired with E18 depend on the specific biological context, as "E18" is a designation found across different fields (e.g., anti-Bcl-XL [E18] antibody used in apoptosis and cancer research, or E18 mAb for Enterovirus A71 research). Below are the most notable examples as reported in recent literature.

1. Anti-Bcl-XL [E18] Antibody (Oncology/Cell Biology Research)

This rabbit monoclonal antibody specifically detects the anti-apoptotic protein Bcl-XL. In experiments involving anti-Bcl-XL [E18], other frequently used antibodies or proteins include:

• Bcl-2: Another anti-apoptotic protein often compared or studied in tandem with Bcl-XL for apoptosis assays.
• Bax and Bad: Pro-apoptotic proteins used to study the balance of cell survival and apoptosis pathways.
• Cleaved Caspase-3: Marker of apoptosis, analyzed when evaluating Bcl-XL function.
• β-actin or GAPDH: Loading controls in Western blot experiments for normalization.
• Secondary antibodies: Commonly anti-rabbit IgG, conjugated to HRP, FITC, or AlexaFluor for detection in Western blot, flow cytometry, or immunofluorescence.

2. E18 or E18-F1 Antibodies (Virology/Enterovirus A71 Research)

In studies investigating Enterovirus A71 (EV71):

• E19 mAb: Another monoclonal antibody against EV71, used together with E18 for structural and neutralization studies.
• Single-domain F1 antibody: Fused to E18 to create a bispecific antibody (E18-F1) for enhanced viral targeting.
• VP1, VP2, VP3, and VP4 viral proteins: These are common antigens for which other monoclonal or polyclonal antibodies are used as comparators or controls.
• Human SCARB2 receptor: Sometimes assessed in parallel, as it is the EV71 entry receptor.
• Secondary antibodies: Anti-human or anti-mouse IgG for detection in ELISA, immunoprecipitation, or immunocytochemistry.

3. HPV E18-Related Antibodies (Virology/Cancer Research)

In studies related to HPV-18 E6/E7 proteins (which can be referred to as E18 in some literature):

• Anti-HPV-16 E6/E7 antibodies: Used in parallel for comparative studies between different HPV types.
• Polyclonal rabbit anti-fusion protein serum: Used for detection and mapping of antibody-reactive regions.
• Synthetic peptides representing E6/E7 regions: Used as antigens for ELISA to detect specific responses in sera of patients.

Contextual Note

If you are referring to a specific use of "E18" (such as a clone, an epitope, or an embryonic timepoint), the associated antibodies or proteins will depend strongly on that context. The above include the most widely documented pairings from recent peer-reviewed literature.

If you clarify the research field or target, more tailored and relevant combinations can be provided.

The term "clone E18" has been cited in distinct scientific contexts, notably in antibody engineering, gene expression/fibroblast biology, and viral genome cloning. Here are the key findings from major citations:

1. Antibody Engineering and Antiviral Activity (Enterovirus A71)

• Clone E18 refers to an IgG antibody specific for Enterovirus A71 (EVA71).
• Researchers developed a bispecific antibody (E18-F1) by fusing a single-domain antibody (sdAb) named F1 to the light chain of E18 IgG.
• Key findings:
  • E18-F1 exhibits improved antiviral activity against EVA71 compared to the original E18 IgG.
  • It offers better virus binding, reduces clinical symptoms, and increases survival in hSCARB2 transgenic mice after lethal EVA71 challenge.
  • The bispecific structure is notable for avoiding steric hindrance, which can reduce antibody efficacy.
  • Quantitatively, the EC50 (the concentration for half-maximal effect) improved from 5.2 nM for E18 to 1.6 nM for E18-F1.
  • At 10 nM, E18-F1 reduced viral load by more than 99.5% in vitro.

2. Gene Expression and Fetal Fibroblast Biology

• In fetal mouse studies, E18 refers to embryonic day 18 fibroblasts, which are compared to earlier stages (e.g., E14) to study scar formation.
• Key findings:
  • At E18, 245 genes are upregulated and 30 genes are downregulated compared to E14 fibroblasts.
  • Upregulated pathways at E18 include those associated with cancer signaling pathways (colorectal, pancreatic, endometrial) and fibrosis.
  • Downregulated pathways in E18 include various biosynthetic processes (e.g., putrescine, S-adenosyl-L-methionine, specific inositol tetrakisphosphates).
  • The transition from E14 to E18 marks a shift from scarless to scar-forming repair, highlighting candidate genes and pathways relevant to regenerative vs. fibrotic healing.
  • These findings narrow the mechanisms underlying scarless fetal wound healing and may guide future therapeutic strategies.

3. Viral Genome Cloning (Herpesvirus)

• In the context of herpesvirus genome cloning, clone E18 refers to a specific BAC-clone of the rat cytomegalovirus (RCMV) genome.
• Key findings:
  • Clone E18 was sequenced and found to be genomically complete, with three polymorphisms in non-coding regions and five in coding regions (one silent).
  • Variants seen in clone E18 reflect those present in the viral DNA used for cloning, not new mutations from cloning techniques.
  • This establishes STAR cloning as a reliable method for capturing diverse viral genome variants present in parental populations.

Summary Table: Clone E18 Scientific Contexts

If you have a specific context for "clone E18," (e.g., antibodies, embryonic development, viral cloning), please clarify so I can target findings even more precisely.

Clone E18, an anti-mouse CD28 monoclonal antibody, exhibits varying dosing regimens across different experimental contexts, though specific dosing information for this clone is limited in the literature compared to other commonly used antibodies.

Functional Characteristics and Applications

Clone E18 recognizes murine CD28, a co-stimulatory molecule expressed on T cell subsets, and has been demonstrated to stimulate murine T lymphocytes when used in combination with anti-mouse CD3 antibodies. The antibody blocks the binding of other CD28-targeting antibodies (such as 37.51) and can costimulate T cell activation and proliferation.

Reported Dosing in Myocardial Infarction Models

In cardiovascular research, clone E18 has been applied as a ligand-binding blocking antibody in myocardial infarction studies. The antibody was administered once on day two after myocardial infarction in wildtype mice, though the specific dose used in this application was not detailed in the available search results.

General Context for Anti-CD28 Dosing

While specific dosing information for clone E18 across multiple mouse models is not extensively documented in the provided sources, the antibody is supplied at a concentration of 1.0 mg/ml and is recommended for use at 10 μL of a 1/50 to 1/100 dilution for labeling 10^6 cells in flow cytometry applications. However, in vivo dosing regimens would typically require substantially higher amounts than those used for in vitro applications.

For comparison, other immune-activating antibodies targeting T cell markers, such as anti-CD3ε (clone 145-2C11), are administered at doses ranging from 5-50 μg per mouse via intravenous injection. Given that CD28 functions as a co-stimulatory molecule alongside CD3, similar dose ranges might be expected for E18 in functional assays, though the specific application and desired outcome would dictate the optimal dosing strategy.

The variation in dosing regimens across different mouse models would likely depend on factors including the mouse strain used, the route of administration, the experimental endpoint being measured, and whether the antibody is being used for blocking, stimulation, or depletion purposes.