Modulation by sodium butyrate of the differentiated status of a clonal pancreatic B-cell line (RIN).
RINmRH cells are a cloned cell line derived from a transplantable rat insulinoma. These cells display only some of the differentiated structure/function features of native pancreatic B-cells. In particular, they do not efficiently or reproducibly express islet B-cell surface antigens, which would otherwise render them useful for screening for the presence of anti-islet cell surface antibodies in the serum of suspected diabetic patients or their relatives. This study examines whether sodium butyrate can enhance expression of B-cell differentiation antigens on RIN cells. RIN cells were exposed to 1,2 or 4 mM butyrate for nine days, and cell growth followed. At 1 mM, butyrate inhibited cell growth by 90%. At the higher concentrations, there was a net loss in the number of cells per culture dish. Exposing the cells to 1 mM or 2 mM butyrate for two days, resulted in a 50% increase in cellular insulin content at the expense of a partial (1 mM) or complete (2 mM) loss of stimulated insulin release in response to glyceraldehyde or serine. A concentration of 1 mM butyrate was therefore used for subsequent studies. The binding to RIN cells of a panel of monoclonal antibodies (mAb's) known to bind native islet cells (R2D6, A2B5, A1D2, 3G5) as well as of serum from a diabetic patient known to carry anti-islet cell antibodies, was screened by cytofluorography or by a radio-binding assay. The relative binding affinity of the mAb's was 3G5 greater than A1D2 greater than A2B5 greater than R2D6. Only 2-3% of the cells were bound by the diabetic patient serum.(ABSTRACT TRUNCATED AT 250 WORDS)
Gardner
S L
SL
E.P. Joslin Research Laboratories, Brigham and Women's Hospital, Boston, MA.
Dotta
F
F
Nayak
R C
RC
George
K L
KL
Eisenbarth
G S
GS
Halban
P A
PA
D000818:Animals; D000911:Antibodies, Monoclonal; D001323:Autoantibodies / Q000032:analysis; D002087:Butyrates / Q000494:pharmacology*; D020148:Butyric Acid; D002454:Cell Differentiation / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D046508:Culture Techniques / Q000379:methods; D004273:DNA, Neoplasm / Q000032:analysis; D003920:Diabetes Mellitus / Q000097:blood; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007340:Insulinoma; D010190:Pancreatic Neoplasms; D014407:Tumor Cells, Cultured / Q000166:cytology* / Q000187:drug effects / Q000276:immunology
D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D002087:Butyrates; D004273:DNA, Neoplasm; D007328:Insulin; C024211:islet cell antibody; D020148:Butyric Acid