Table 2.

Effector B cell responses in humoral alloimmunity in transplantation

Model	location	Effector B cell immune state and function	References
human kidney transplant recipients	circulating B cells	increased T-bet+CD27+CD21+ memory B cells transcriptionally and functionally poised for plasma cell differentiation in ABMR	[48]
human kidney transplant recipients	intragraft B cells	intragraft B cells have transcriptional resemblance with mouse innate B cells with capacity to differentiate into plasma cells expressing self-reactive antibodies, driven by local intragraft antigens	[49]
rat kidney transplant	GC B cells	CD45R+CD27+ memory B cells in splenic follicles from rats with ABMR, which can be diminished by high cyclosporine treatment	[12]
mouse heart transplant	GC B cells	Alloreactive B cells contribute to transplantation tolerance by foregoing germinal center responses while retaining their ability to function as antigen-presenting cells and by actively suppressing de novo alloreactive B cell responses	[50]
mouse skin transplant	GC B cells	increased GL-7+CD95+ B cells correlate with ICOS+ PD-1 cTfh expansion and precedes DSA formation, which can be diminished by belatacept and anti-CD28 treatment	[19]
rat kidney transplant	GC B cells	presence of B cell follicles and AID mRNA in spleen of rats in ABMR model (low cyclosporine-induced) which can be diminished by anti-BAFF treatment	[51]
human kidney transplant recipients	circulating B cells	expansion of Ki67+CD20hiCD38loCD27+IgD- activated B cells in DSA+ABMR+ versus DSA+ABMR- patients	[17]
human kidney transplant recipients	circulating B cells	CD27-IgD+ anive and CD27+IgD− memory B cells detected in highly sensitized patients, which were decreased after desensitization by belatacept and proteasome inhibitor	[52]
human kidney transplant recipients	circulating B cells	increased IgD-CD27+CD38- memory B cells at time of DSA detection before onset of ABMR	[53]
human kidney transplant recipients	circulating B cells	high frequencies of donor-specific memory B cells in patients with acute and chronic ABMR	[54]
human kidney transplant recipients	circulating B cells	donor-specific memory B cells are detected by ELISPOT before transplantation in sensitized patients	[55]
non human primate kidney transplant	circulating B cells	increased blood Ki67+CD20+CD27+IgD− memory B cells in sensitized primated with ABMR after T cell–depleting induction	[31]
human kidney transplant recipients	circulating B cells	expansion of CD19+CD27-IgD- and IL-21R+ B cells in patients developping anti-HLA antibodies	[56]
human kidney transplant recipients	circulating B cells	high frequencies of donor-specific memory B cells are found at ABMR diagnosis and before transplantation, regardless of circulating DSA	[57]
non human primate kidney transplant	circulating B cells	presence of CD20+CD27+ B cells in ABMR which could be decreased by anti-CD40 and belatacept treatment	[33]
human kidney transplant recipients	circulating B cells	increased IgD-CD27+ switched memory and decreased IgD+ CD27- naive B cells during the first month post-transplant predicted de novo DSA development	[58]