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

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

Product No.: C2471

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Clone
E18
Target
CD28
Formats AvailableView All
Product Type
Hybridoma Monoclonal Antibody
Alternate Names
T-cell-specific surface glycoprotein CD28, Tp44, T44
Isotype
Mouse IgG2b κ
Applications
Agonist
,
B
,
FA
,
FC

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Select Product Size
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Antibody Details

Product Details

Reactive Species
Mouse
Host Species
Mouse
Recommended Dilution Buffer
Immunogen
CD28 -/- mice were alternately immunized with A20 cells expressing mCD28 and recombinant mCD28Ig
Product Concentration
≥ 5.0 mg/ml
Endotoxin Level
< 1.0 EU/mg as determined by the LAL method
Purity
≥95% monomer by analytical SEC
>95% by SDS Page
Formulation
This monoclonal antibody is aseptically packaged and formulated in 0.01 M phosphate buffered saline (150 mM NaCl) PBS pH 7.2 - 7.4 with no carrier protein, potassium, calcium or preservatives added. Due to inherent biochemical properties of antibodies, certain products may be prone to precipitation over time. Precipitation may be removed by aseptic centrifugation and/or filtration.
State of Matter
Liquid
Product Preparation
Functional grade preclinical antibodies are manufactured in an animal free facility using only in vitro protein free cell culture techniques and are purified by a multi-step process including the use of protein A or G to assure extremely low levels of endotoxins, leachable protein A or aggregates.
Storage and Handling
Functional grade preclinical antibodies may be stored sterile as received at 2-8°C for up to one month. For longer term storage, aseptically aliquot in working volumes without diluting and store at ≤ -70°C. Avoid Repeated Freeze Thaw Cycles.
Regulatory Status
Research Use Only
Country of Origin
USA
Shipping
2 – 8° C Wet Ice
Additional Applications Reported In Literature ?
Agonist,
B,
FA,
FC
Each investigator should determine their own optimal working dilution for specific applications. See directions on lot specific datasheets, as information may periodically change.

Description

Description

Specificity
E18 activity is directed against mouse CD28 at an epitope close to the B7 binding site.
Background
CD28 is a 44 kD glycoprotein and member of the Ig superfamily that produces co-stimulatory signals necessary for T cell activation and survival as part of the B7-1/B7-2–CD28/CTLA-4 pathway1. The two B7 family proteins, B7-1 (CD80) and B7-2 (CD86), have dual specificity for the stimulatory receptor CD28 and the inhibitory receptor CTLA-4 (CD152). When B7-1 and B7-2 interact with CD28, an important co-stimulatory signal, transmitted via CD28, synergizes with the TCR signal to regulate the threshold for T cell activation and promote T cell survival, clonal expansion, and differentiation. CD28 also promotes interleukin-2 (IL-2) production. In contrast, when B7-1 and B7-2 engage with CTLA-4, a negative signal inhibits TCR- and CD28- mediated signaling as well as IL-2 synthesis, and the T-cell response is terminated.

E18 was generated by alternately immunizing CD28-/- mice with A20 cells expressing mCD28 and recombinant mCD28Ig2. Splenic cells were fused with X63Ag8.653 for hybridoma production. E18 completely blocks CD28 ligation by B7 molecules3. Additionally, E18 enhances anti-CD3-induced proliferation of peripheral T cells. In vivo, E18 acts as an inhibitor of CD28 signaling and causes a reversible reduction in Treg cell frequencies among CD4+ cells.
Antigen Distribution
CD28 is constitutively expressed on the surface of T cells.
Ligand/Receptor
CD80 (B7-1), CD86 (B7-2), GRB2, PIK3R1, PRKCQ
NCBI Gene Bank ID
UniProt.org
Research Area
Costimulatory Molecules
.
Immunology
.
Immunoglobulins

Leinco Antibody Advisor

Powered by AI: AI is experimental and still learning how to provide the best assistance. It may occasionally generate incorrect or incomplete responses. Please do not rely solely on its recommendations when making purchasing decisions or designing experiments.

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

FieldContext of "Clone E18"Key Findings
Antibody engineeringEVA71-specific IgG (antibody E18)E18-F1 bispecific antibody has improved antiviral efficacy over clone E18 against EVA71 in vitro and in vivo
Fetal biology/gene expressionE18 fetal fibroblasts (E18 vs E14)Marked gene expression changes reflect transition from scarless to fibrotic repair during development
Viral genome cloningRCMV BAC clone E18E18 genome is complete; SNPs reflect inherent viral pool diversity, not cloning artifacts

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.

References & Citations

1. Sharpe AH, Freeman GJ. Nat Rev Immunol. 2(2):116-126. 2002.
2. Dennehy KM, Elias F, Zeder-Lutz G, et al. J Immunol. 176(10):5725-5729. 2006.
3. Beyersdorf N, Ding X, Blank G, et al. Blood. 112(10):4328-4336. 2008.
4. Langenhorst D, Haack S, Göb S, et al. Front Immunol. 9:1060. 2018.
5. Gladow N, Hollmann C, Ramos G, et al. PLoS One. 15(4):e0227734. 2020.
Agonist
B
FA
Flow Cytometry

Certificate of Analysis

Formats Available

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Disclaimer AlertProducts are for research use only. Not for use in diagnostic or therapeutic procedures.