B cell development and proliferation of mature B cells in human fetal intestine.
B cells are present in human fetal intestine from approximately 14 weeks of gestation. Here we show that this population includes mature, dividing B cells. These are large cells with dendritic processes, resembling human thymic B cells. In addition, we observed IgM+, light chain-, and CD20- cells and local expression of V pre-B, demonstrating that the human fetal intestine is a site of B cell development. Ig V(H)DJ(H) gene sequencing can confirm clonal identity of B cells. Identification of the same IgV(H)4-34 sequence in serial sections in two fetuses confirmed local accumulation of related cells in each case. IgV(H)4-34 was also amplified from an additional two samples, and the D and J repertoire compared with a unique database of unselected V(H)4-34 genes from postnatal gut. Distinguishing characteristics of Ig lambda genes in postnatal gut were also studied in the fetus. According to these parameters, fetal and postnatal B cells are unrelated.
Golby
Sarah
S
Department of Histopathology, GKT Medical School, St. Thomas' Campus, London, United Kingdom.
Hackett
Maggie
M
Boursier
Laurent
L
Dunn-Walters
Deborah
D
Thiagamoorthy
Sivashankari
S
Spencer
Jo
J
D000328:Adult; D000483:Alleles; D001402:B-Lymphocytes / Q000166:cytology*; D001483:Base Sequence; D018956:CD5 Antigens / Q000032:analysis; D002454:Cell Differentiation; D019070:Cell Lineage; D004254:DNA Nucleotidyltransferases / Q000378:metabolism; D015322:Gene Rearrangement, B-Lymphocyte; D005803:Genes, Immunoglobulin; D005865:Gestational Age; D006801:Humans; D007107:Immune System / Q000196:embryology*; D017578:Immunoglobulin Class Switching; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007133:Immunoglobulin Joining Region / Q000235:genetics; D007075:Immunoglobulin M / Q000096:biosynthesis; D007135:Immunoglobulin Variable Region / Q000235:genetics; D007146:Immunoglobulin lambda-Chains / Q000235:genetics; D007422:Intestines / Q000196:embryology* / Q000276:immunology; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D045567:VDJ Recombinases
D018956:CD5 Antigens; D007143:Immunoglobulin Heavy Chains; D007133:Immunoglobulin Joining Region; D007075:Immunoglobulin M; D007135:Immunoglobulin Variable Region; D007146:Immunoglobulin lambda-Chains; D004254:DNA Nucleotidyltransferases; D045567:VDJ Recombinases