A TCR transgenic mouse reactive with multiple systemic dimorphic fungi

Area of Science:

• Immunology
• Mycology
• Infectious Diseases

Background:

• Dimorphic fungi cause millions of infections annually, necessitating better understanding of host resistance mechanisms.
• Current research faces limitations in tools for studying fungus-specific T cell responses during vaccination and infection.
• Developing effective vaccines against these fungi requires detailed knowledge of cellular immunity.

Purpose of the Study:

• To characterize a novel TCR transgenic mouse model (Bd 1807) for studying T cell responses to dimorphic fungi.
• To evaluate the utility of this model in assessing antifungal immunity and vaccine efficacy.
• To investigate the duration of antigen presentation and CD4+ T cell memory development.

Main Methods:

• Generation of a TCR transgenic mouse (Bd 1807) with CD4+ T cells reactive to dimorphic fungi.
• Adoptive transfer of 1807 cells into vaccinated wild-type mice.
• Analysis of T cell activation, proliferation, differentiation, and trafficking following fungal challenge.
• Assessment of vaccine-induced resistance conferred by 1807 cells.

Main Results:

• The Bd 1807 mouse model's CD4+ T cells respond to Blastomyces dermatitidis, Histoplasma capsulatum, Coccidioides posadasii, and Paracoccidioides lutzii.
• Adoptively transferred 1807 cells differentiate into T1 effectors and confer vaccine-induced resistance against multiple fungal species.
• The study revealed prolonged fungal antigen presentation and maximal effector/memory CD4+ T cell pool by 4 weeks post-vaccination.

Conclusions:

• The Bd 1807 mouse model provides a powerful tool for studying antifungal immunity and T cell differentiation against multiple dimorphic fungi.
• This model facilitates research into CD4+ T cell memory development crucial for protection against fungal infections.
• The findings offer novel insights into antifungal immune responses and vaccine strategies.