Role of the spleen in peripheral memory B-cell homeostasis in patients with autoimmune thrombocytopenia purpura

Clin Immunol. 2009 Feb;130(2):199-212. doi: 10.1016/j.clim.2008.09.009. Epub 2008 Oct 31.


The effect of splenectomy on circulating memory B cells in autoimmune thrombocytopenia purpura (AITP) patients has not yet been addressed. We therefore analyzed the distribution and phenotypic characteristics of B-cell subsets in non-splenectomized and splenectomized AITP patients and controls, as well as CD95 expression after B cell activation. Decreased frequencies of memory B cells in splenectomized individuals were observed, with a rapid decline of CD27+IgD+ and a slower decrease of CD27+IgD- and CD27-/IgD- cells. Similar results were noted following splenectomy in healthy donors (HD). CD95+ B cells were substantially increased in all subsets in patients with active AITP, indicating their enhanced activation status. After splenectomy, the percentage of CD95+ B cells were further increased in the CD27+IgD- post-switch memory population in AITP, but not in HD. CD95+CD27+ memory B cells largely reside in the region in the human spleen analogous to the murine marginal zone. Thus, the spleen plays a fundamental role in controlling peripheral memory B cell homeostasis in both AITP and HD and regulates activated CD95+ B cells in patients with AITP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • B-Lymphocyte Subsets / immunology*
  • B-Lymphocyte Subsets / metabolism
  • Female
  • Homeostasis / immunology
  • Humans
  • Immunologic Memory*
  • Lymphocyte Activation / immunology
  • Male
  • Middle Aged
  • Purpura, Thrombocytopenic, Idiopathic / immunology*
  • Purpura, Thrombocytopenic, Idiopathic / metabolism
  • Purpura, Thrombocytopenic, Idiopathic / pathology
  • Spleen / immunology*
  • Spleen / pathology
  • Spleen / surgery
  • Splenectomy