B Cell–Intrinsic and –Extrinsic Regulation of Antibody Responses by PARP14, an Intracellular (ADP-Ribosyl)Transferase

Abstract

The capacity to achieve sufficient concentrations of Ag-specific Ab of the appropriate isotypes is a critical component of immunity that requires efficient differentiation and interactions of Ag-specific B and T helper (Th) cells along with dendritic cells. Numerous bacterial toxins catalyze mono-(ADP-ribosyl)ation of mammalian proteins to impact cell physiology and adaptive immunity. However, little is known about biological functions of intracellular mammalian mono-(ADP-ribosyl)transferases (mART), such as any ability to regulate Ab responses. Poly-(ADP-Ribose) Polymerase 14 (PARP14), an intracellular protein highly expressed in lymphoid cells, binds to STAT6 and encodes a catalytic domain with mART activity. Here we show that recall IgA as well as the STAT6-dependent IgE Ab responses are impaired in PARP14-deficient mice. Whereas PARP14 regulation of IgE involved a B cell intrinsic process, the predominant impact on IgA was B cell-extrinsic. Of note, PARP14 deficiency reduced the levels of Th17 cells and CD103+ DCs which are implicated in IgA regulation. PARP14 enhanced the expression of RORα, Runx1 and Smad3 after T cell activation, and, importantly, its catalytic activity of PARP14 promoted Th17 differentiation. Collectively, the findings show that PARP14 influences the class distribution, affinity repertoire, and recall capacity of antibody responses in mice, and provide direct evidence of requirement for protein mono-ADP-ribosylation in T helper differentiation.

Bordetella pertussis outer membrane vesicle vaccine confers equal efficacy in mice with milder inflammatory responses compared to a whole-cell vaccine

“…This group included genes on immune cells such as C4b, Cd83 an important activation marker on B-cell, T-cell, and dendritic cell populations44, Fcgr3 , Ighm, Irf9 , Ly6e , and Parp14 . PARP-14 promotes Th2 and Th17 cell formation and steers the antibody subclass distribution4546.…”

Germinal centre hypoxia and regulation of antibody qualities by a hypoxia response system

“…After collection of pre-immune sera, mice were immunized with NP 16 -ovalbumin (OVA) (100 µg intraperitoneally) in alum (Imject, Thermo Fisher Scientific, Waltham MA) as described 33 . Alternatively, this primary immunogen was mixed with NP-modified SRBC, followed by a boost with NP-ovalbumin in alum.…”

“…Relative levels of anti-NP Ab in immune sera were assayed by ELISA on serial dilutions binding to either NP20-BSA (high valency, to capture all affinities of Ab) or NP2 (low valency, to restrict binding to the high-affinity Ab). Specific classes or isotypes were then detected using the series of isotype-specific second Ab of the SBA Clonotyping System (Southern Biotech, Birmingham AL), as described 33 . Data for Ag-specific Ab are shown after subtraction of low OD values from pre-immune controls analyzed together with the immune sera and were separately determined to match values yielded by titration.…”

“…Data for Ag-specific Ab are shown after subtraction of low OD values from pre-immune controls analyzed together with the immune sera and were separately determined to match values yielded by titration. Ab-secreting cells (ASC) were analyzed by ELISpot as previously described 33 and quantitated using an ImmunoSpot Analyzer (Cellular Technology, Shaker Heights OH). Ag-specific B cells were detected and enumerated using flow cytometry to score B lineage-marked cells binding to fluor (APC or rPE)-conjugated NP, using a dump channel (7-AAD and APC-conjugated mAb against IgD, F4/80, Gr1, CD11b, CD11c, CD4, and CD8) to exclude non-specific signal.…”

PARPs and ADP-ribosylation: recent advances linking molecular functions to biological outcomes

“…For example, PARP-14 regulates the class distribution, affinity repertoire, and recall capacity of antibody responses, which require efficient differentiation and interactions among B cells, Th cells, and dendritic cells (Cho et al 2013). Furthermore, PARP-14 is required for IL-4-dependent enhancement of glycolysis in B cells as well as Myc-induced oncogenesis (Cho et al 2011).…”