The microRNA processing subunit DGCR8 is required for a T cell-dependent germinal center response

Patrick, D.; Meinzinger, J.; Schulz, S. R.; Corte-Real, J.; Hauke, M.; Roth, E.; Schuh, W.; Mielenz, D.; Wittmann, J.; Jäck, H.-M.; Pracht, K.

doi:10.1101/2022.07.31.501995

bioRxiv · 10.1101/2022.07.31.501995

The microRNA processing subunit DGCR8 is required for a T cell-dependent germinal center response

Patrick, D.·Meinzinger, J.·Schulz, S. R.·Corte-Real, J.·Hauke, M.·Roth, E.·Schuh, W.·Mielenz, D.·Wittmann, J.·Jäck, H.-M.·Pracht, K.

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Abstract

We have previously shown that the microRNA (miRNA) processor complex consisting of the RNAse Drosha and the DiGeorge Critical Region (DGCR) 8 protein is essential for central B cell maturation. To determine whether miRNA processing is required to initiate T cell-mediated antibody responses, we deleted DGCR8 in maturing B-2 cells by crossing a mouse with loxP-flanked DGCR8 alleles with a CD23-Cre mouse. As expected, non-immunized mice showed reduced numbers of mature B-2 cells and IgG-secreting cells and diminished serum IgG titers. In accordance, germinal centers and antigen-specific IgG-secreting cells were absent in mice immunized with T cell-dependent antigens. Therefore, DGCR8 is required to mount an efficient T cell-dependent antibody response. However, DGCR8 deletion in B-1 cells was incomplete, which explains relatively unaffected B-1 cell numbers and adequate IgM and IgA titers in DGCR8-knock out mice and suggests that this mouse model could be used to analyze B-1 responses in the absence of functional B-2 cells.

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Patrick, D., Meinzinger, J., Schulz, S. R., Corte-Real, J., Hauke, M., Roth, E., Schuh, W., Mielenz, D., Wittmann, J., Jäck, H.-M., Pracht, K.. 2022-08-02. The microRNA processing subunit DGCR8 is required for a T cell-dependent germinal center response. https://doi.org/10.1101/2022.07.31.501995

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