IMMUNOLOGY2026™ Conference Recordings For Attendees-Absence of the "Don't Eat Me" signal results in aberrant T cell responses to Leishmania major

Absence of the "Don't Eat Me" signal results in aberrant T cell responses to Leishmania major

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Video Summary

This talk focused on cutaneous leishmaniasis, a common neglected tropical disease caused by Leishmania parasites transmitted by sandflies. Unlike visceral disease, it causes persistent skin lesions that can take months to heal. The presenter explained that protection depends largely on a Th1 immune response, especially interferon-gamma and TNF-alpha, which help macrophages kill the parasite.<br /><br />The main study examined the CD47–SIRPα “don’t eat me” signaling pathway in Leishmania major infection. Mice lacking either CD47 or SIRPα were highly susceptible, showing earlier and larger lesions, higher parasite burdens, smaller draining lymph nodes, and enlarged spleens. Immune analysis showed altered T-cell numbers and activation, with chronic mice producing less protective cytokines, although early infection sometimes showed strong Th1-like responses. Overall, the data suggest CD47/SIRPα influences both innate and adaptive immunity during infection, and the exact mechanism is still being investigated.

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Date April 17, 2026 5:30 PM - 5:45 PM

Room 153C

Session Signaling Pathways Modulating Immune Responses to Microbial Infections

Speaker Hanna Paton

Track Microbial, Parasitic, and Fungal Immunology (MPF)

Year 2026

Keywords

cutaneous leishmaniasis

Leishmania major

CD47-SIRPα pathway

Th1 immune response

parasite burden

April 17, 2026 5:30 PM - 5:45 PM

153C

Signaling Pathways Modulating Immune Responses to Microbial Infections

Hanna Paton

Microbial, Parasitic, and Fungal Immunology (MPF)

2026