An Intradermal Model for Yersinia pestis Inoculation

Area of Science:

• Immunology
• Infectious Diseases
• Dermatology

Background:

• The dermis and subcutaneous space differ significantly in lymphatic vessels, blood vasculature, and immune cells.
• Subcutaneous inoculation is traditionally used for Yersinia pestis studies, despite fleas targeting the dermal layer.
• Current models lack biological relevance to natural flea-transmitted Yersinia pestis infections.

Purpose of the Study:

• To establish a more biologically relevant intradermal model for Yersinia pestis infection studies.
• To compare the efficacy of intradermal versus subcutaneous inoculation for Yersinia pestis.
• To investigate the colonization patterns of Yersinia pestis following intradermal inoculation.

Main Methods:

• Development and validation of an intradermal inoculation technique in the murine ear pinna.
• Comparative analysis of Yersinia pestis colonization in lymph nodes, blood, and tissues after intradermal and subcutaneous inoculation.
• Histological and physiological assessment of the murine ear pinna post-intradermal inoculation.

Main Results:

• Intradermal inoculation resulted in robust and reproducible colonization of lymph nodes, blood, and deeper tissues.
• The intradermal model mimics natural flea transmission more closely than subcutaneous models.
• Intradermal inoculation in the murine ear pinna allowed for the study of cutaneous infection without significant disruption to skin architecture.

Conclusions:

• An intradermal inoculation model provides a superior and biologically relevant approach for studying Yersinia pestis and bubonic plague.
• This model facilitates reproducible investigations into pathogen dissemination and host-pathogen interactions.
• The murine ear pinna serves as an effective site for studying cutaneous Yersinia pestis infections.