Cell-mediated immunity in experimental Nocardia asteroides infection

Area of Science:

• Immunology
• Microbiology
• Infectious Diseases

Background:

• Mycetoma is a chronic fungal or bacterial infection.
• Nocardia asteroides causes mycetoma-like lesions.
• The immune response to Nocardia asteroides is not fully understood.

Purpose of the Study:

• To investigate the role of cell-mediated immunity in experimental mycetoma-like lesions.
• To determine if cell-mediated immunity can be transferred to confer protection.

Main Methods:

• Induction of mycetoma-like lesions in guinea pigs using Nocardia asteroides.
• Assessment of delayed hypersensitivity, macrophage migration inhibition, and microbicidal activity.
• Spleen cell transfer from healed donors to naive recipients.
• Challenge of recipient animals with Nocardia asteroides.

Main Results:

• Delayed hypersensitivity appeared early in the infection.
• Increased macrophage migration inhibition and microbicidal activity were observed after 7 weeks.
• High cell-mediated immunity was present upon lesion healing.
• Adoptive transfer of spleen cells from healed guinea pigs conferred protection against N. asteroides challenge.

Conclusions:

• Cell-mediated immunity is essential for the resolution of Nocardia asteroides-induced mycetoma-like lesions.
• Cell-mediated immunity can be adoptively transferred, providing protection against infection.
• This study highlights the potential of immunotherapy for mycetoma.