title: CD38 induces differentiation of immature transitional 2 B lymphocytes in the spleen.
abstract: CD38 is a surface receptor able to induce activation, proliferation, and survival of human and mouse lymphocytes; this molecule is expressed on the surface of both mature and immature B cells. In this work, the function of CD38 in the maturation of murine B lymphocytes in the spleen was analyzed. The results showed that CD38 is highly expressed on Transitional 2 (T2) B lymphocytes with an intermediate expression on Transitional 1 (T1) and mature follicular B cells (M). Correlating with a high expression of CD38, T2 cells are also larger and more granular than T1 or M B cells. T2 cells also showed high levels of other molecules, which indicate an activated phenotype. CD38 crosslinking induced proliferation and maturation of T2 B lymphocytes; in contrast, T1 subset died by apoptosis. Finally, CD38 stimulation of T2 B lymphocytes obtained from Btk-, Lyn-, or Fyn-deficient mice showed a defective differentiation; similarly, drugs interfering with PI3K or ERK decreased the proliferation or differentiation of this subset. This suggests that these molecules participate in the CD38 signaling pathway. As a whole, the results indicate that CD38 plays an important role in the regulation of B-cell maturation in the spleen.
authors.affiliation: Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados, and Universidad Nacional Autónoma de México, México City, Mexico.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Rodríguez-Alba
authors.forename: Miguel E
authors.initials: ME
authors.lastname: Moreno-García
authors.forename: Claudia
authors.initials: C
authors.lastname: Sandoval-Montes
authors.forename: Víctor H
authors.initials: VH
authors.lastname: Rosales-Garcia
authors.forename: Leopoldo
authors.initials: L
authors.lastname: Santos-Argumedo
mesh_terms: D051997:ADP-ribosyl Cyclase 1 / Q000235:genetics / Q000276:immunology*; D000077329:Agammaglobulinaemia Tyrosine Kinase; D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology*; D049109:Cell Proliferation; D002470:Cell Survival / Q000235:genetics / Q000276:immunology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000235:genetics / Q000276:immunology; D005786:Gene Expression Regulation / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007152:Immunologic Capping / Q000235:genetics / Q000276:immunology; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology; D008562:Membrane Glycoproteins / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000276:immunology; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000276:immunology; D051076:Proto-Oncogene Proteins c-fyn / Q000235:genetics / Q000276:immunology; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology*; D013154:Spleen / Q000166:cytology / Q000276:immunology*; D019061:src-Family Kinases / Q000235:genetics / Q000276:immunology
chemical_list: D008562:Membrane Glycoproteins; D019869:Phosphatidylinositol 3-Kinases; D011505:Protein-Tyrosine Kinases; D000077329:Agammaglobulinaemia Tyrosine Kinase; C000625949:BTK protein, human; C494960:Fyn protein, mouse; D051076:Proto-Oncogene Proteins c-fyn; C060902:lyn protein-tyrosine kinase; D019061:src-Family Kinases; D048049:Extracellular Signal-Regulated MAP Kinases; C498155:Cd38 protein, mouse; D051997:ADP-ribosyl Cyclase 1