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DTSTART;TZID=America/Chicago:20260423T111500
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DTSTAMP:20260415T123554Z
SUMMARY:Appl Math: Ned Wingreen on "Collective dynamics in B cell affinity maturation"
UID:641639@northwestern.edu
TZID:America/Chicago
DESCRIPTION:Title: Collective dynamics in B cell affinity maturation  Speaker: Ned Wingreen\, Princeton University  Abstract: In the humoral immune response\, B cells that produce high-affinity antibodies are generated through a Darwinian evolutionary process called affinity maturation. Affinity maturation\, which takes place in germinal centers (GC)\, is driven by cycles of selection (mediated by T cells)\, division\, and hypermutation of B cells. Recently\, it was found that the T cells themselves also exhibit dynamic behavior throughout the course of the GC reaction\, undergoing affinity-dependent proliferation. A model suggests that this reciprocal stimulation enforces a robust “homeostatic” regulation of the relative number of B cells and T cells in the GC\, leading to a constant ratio of GC lymphocytes. But the model also points to a problem: the high mutation rate of GC B cells can lead to “backsliding” of affinity. The proposed solution – a fitness-dependent mutation rate – has been experimentally verified\, and has implications beyond B cell affinity maturation.  Zoom: TBA  -----  To subscribe to the Applied Mathematics Colloquia List send a message to LISTSERV@LISTSERV.IT.NORTHWESTERN.EDU with the command:  SUBSCRIBE esam-seminar FirstName LastName
LOCATION:Technological Institute\, M416\, 2145 Sheridan Road\, Evanston\, IL 60208
TRANSP:OPAQUE
URL:https://planitpurple.northwestern.edu/event/641639
CREATED:20260411T050000Z
STATUS:CONFIRMED
LAST-MODIFIED:20260413T161137Z
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