Yersinia pestis targets neutrophils via complement receptor 3

Area of Science:

• Immunology
• Microbiology
• Bacterial Pathogenesis

Background:

• Yersinia species infect lymphoid tissues and use type III secretion systems to deliver toxins to immune cells.
• The precise mechanisms Yersinia uses to select specific host immune cells for attack are not fully understood.

Purpose of the Study:

• To investigate the interaction of Yersinia pestis with murine splenocytes.
• To identify the factors involved in Y. pestis targeting of innate immune cells, particularly neutrophils.

Main Methods:

• Studied Y. pestis interactions with primary murine immune cells.
• Investigated the role of bacterial adhesin Ail.
• Examined the influence of host serum factors, including antibodies against complement receptor 3 and CD14.

Main Results:

• Bacterial adhesin Ail is necessary for efficient Y. pestis targeting of neutrophils in vivo.
• Host serum factors, not bacterial adhesins, primarily direct Y. pestis to neutrophils.
• Absence of bacterial adhesins enhanced neutrophil specificity in the presence of mouse serum.
• Blocking complement receptor 3 and CD14 disrupted Y. pestis target cell selection.

Conclusions:

• Host serum factors, particularly complement receptor 3 and CD14, play a crucial role in directing Yersinia pestis to neutrophils.
• Yersinia pestis employs a combination of bacterial and host factors for immune cell targeting during infection.
• Understanding these interactions is vital for developing strategies against plague infection.