Delayed-Type Hypersensitivity (DTH) Model

Evaluate antigen-specific inflammation and immune-mediated swelling with a reproducible T-cell–driven hypersensitivity assay.

The delayed-type hypersensitivity (DTH) model has been used for decades to evaluate a compound’s ability to modulate swelling and cellular infiltration in response to antigen challenge. Sensitization and challenge with sheep red blood cells (SRBCs) produce a reliable inflammatory response with clear, quantifiable readouts for assessing anti-inflammatory or immunomodulatory therapies within a rapid study timeline.

A Focused Model for T-Cell–Mediated Inflammation

The delayed-type hypersensitivity model provides a reproducible system for studying antigen-specific inflammation following SRBC sensitization and challenge. The response includes localized swelling, immune-cell infiltration, and cytokine activity, offering clear endpoints for evaluating therapeutic effects. With a typical turnaround of 2 to 3 weeks, this model supports both screening studies and targeted mechanism-of-action programs.

Advantages of the Delayed-Type Hypersensitivity Model

This DTH model supports evaluation of therapies targeting localized, antigen-driven inflammation.

  • Reliable activation of adaptive immunity
    SRBC sensitization produces a consistent T-cell-mediated DTH response that supports comparative testing across treatment groups.
  • Clear separation between sensitization and challenge phases
    The two-step design allows investigation of compounds that act at either the priming or effector stages of the immune response.
  • Multiple tissue-level endpoints available
    In addition to paw thickness measurements, studies can include histological scoring of infiltrating immune cells or profiling of local cytokine activity.
  • Straightforward integration into broader inflammation programs
    The model complements other hypersensitivity assays and provides a practical way to benchmark immunomodulatory compounds early in development.

This model is included in our theraTRACE® platform

Ready to get started or looking for a custom model?

Contact us today for more information about our flexible DTH study designs, including optional tissue or cellular endpoints tailored to your research goals.

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    Sridharan Rajamani, Ph.D., Senior Research Scientist

    Gilead Sciences
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    Jay Lichter

    Avalon Ventures
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    Richard DiMarchi, PhD

    Cox Professor of Chemistry & Gill Chair in Biomolecular Sciences Indiana University, Department of Chemistry
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    Modifi Bio
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    Bruce Ruggeri, Ph.D.

    Modifi Bio
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    Maxine Gowen

    Tamuro Bio
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    Tamuro Bio
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    SFA Therapeutics

delayed-type hypersensitivity

Figure 1. Paw thickness in delayed-type hypersensitivity. Animals were sensitized to sheep red blood cells (SRBCs) on day 1 via IV route and challenged on day 6 via footpad injection. Animals were dosed with vehicle or 20 mg/kg dexamethasone 30 minutes prior to the day 6 challenge. On day 7, animals were dosed once more with vehicle or 20 mg/kg dexamethasone, and 30 minutes later, paw thickness was measured using microcalipers. The dexamethasone group displayed a decreased inflammatory response compared to vehicle (***p<0.001). Data were analyzed using an unpaired t-test.

Get the data you need with expert implementation on tight timelines

Reliable induction and challenge procedures

Reliable induction and challenge procedures

Efficient 2 to 3 week study timelines

Efficient 2 to 3 week study timelines

Custom DTH study designs for your goals

Custom DTH study designs for your goals

Frequently Asked Questions

Can DTH studies be designed for both preventative and therapeutic dosing?

Yes. Compounds can be administered before or after the antigen challenge, depending on the mechanism you want to evaluate.

What types of readouts can be included in a DTH study?

Standard endpoints include paw thickness and histological assessment of immune-cell infiltration. Additional tissue or cytokine analyses can be added upon request.

What antigen is used in Melior’s DTH model?

Melior uses sheep red blood cells (SRBCs) to induce a reproducible, antigen-specific response.