Profiling myeloid and B-cells responses during plasmodium chabaudi infection

• Main Author: Tan, Yu You
• Other Authors: Christiane Ruedl
• Format: Final Year Project
• Language: English
• Published: 2016
• Subjects: DRNTU::Science
• Online Access: http://hdl.handle.net/10356/67330
• Institution: Nanyang Technological University

The role of splenic CD169+ macrophages as antigen presenting cells (APCs) have long been suggested by numerous studies. It was reported that during infections, these CD169+ macrophages are able to traverse from the marginal zone (MZ) into the germinal centers (GCs), thus giving us a glimpse of its role in the delivery of foreign antigens during humoral immunity responses. Here, we aim to study the profile of the myeloid and the GC B cell population in response to malaria infection with Plasmodium Chabaudi AS (PccAS). Our results showed that after infection, from approximately 10 days post infection (DPI), there was a significant loss of CD169+ macrophages in all the three organs (lung, liver and spleen) harvested in our study. The loss was less profound in the lung as compared to the liver and spleen. In the lung, we observed the restoration of the CD169+ macrophages as early as 14 DPI. However, in the liver and spleen, the CD169+ macrophages was still not restored even at 35 DPI. Besides studying the CD169+ macrophages population through Fluorescence Activated Cell Sorting (FACS), we also observed for the maturation of monocytes, the development of T follicular helper (TfH) cells and GC response during infection. Despite the loss of the CD169+ macrophages, there were no indications of any impairment in the TfH and GC response. We therefore hypothesize that CD169+ macrophages may not be strictly required in the development of humoral immunity as dendritic cells (DCs) are still the primary APCs. However, further study using the CD169-DTR mice is still required to determine if there is any impairment in the GC and TfH response as compared to the Wildtype group.