TY - JOUR
T1 - Expression of 2 immunoglobulin isotypes, IgM and IgA, with identical idiotype in the B cell lymphoma 1.29
AU - Sitia, R.
AU - Rubartelli, A.
AU - Hammerling, U.
PY - 1981
Y1 - 1981
N2 - The 1.29 tumor originated in I strain mice as a B cell lymphoma. In its ascitic form, the cells express Ia and Lyb antigens and carry the Fc receptor. The tumor cells synthesize 2 immunoglobulins, IgM and IgA, which have λ-chains and heavy chain idiotypic determinants in common. Double labeling of viable cells in immunofluorescence demonstrates that a majority of cells have only IgM (μ
+), a proportion has only IgA (α
+), and a small population (usually less that 5%) expresses both immunoglobulin isotypes (μ
+ α
+). Although the relative proportions of μ
+, α
+, and μ
+α
+ cells fluctuate quite markedly in the serial passages of the tumor, the 3 different subpopulations are consistently observed. The proportion of cells binding fluorescein-labeled anti-μ and rhodamine-labeled anti-α simultaneously in the cytoplasm is slightly higher (+IgA
- 1.29 cells, suggesting differentiation rather than selective growth as the cause of the change. Cloning of 1.29 cells by the limiting dilution technique yielded only cell lines of IgM
-IgA
+ phenotype. Implantation of 1 such cell line in nude mice produced a tumor that retained this phenotype in successive passages.
AB - The 1.29 tumor originated in I strain mice as a B cell lymphoma. In its ascitic form, the cells express Ia and Lyb antigens and carry the Fc receptor. The tumor cells synthesize 2 immunoglobulins, IgM and IgA, which have λ-chains and heavy chain idiotypic determinants in common. Double labeling of viable cells in immunofluorescence demonstrates that a majority of cells have only IgM (μ
+), a proportion has only IgA (α
+), and a small population (usually less that 5%) expresses both immunoglobulin isotypes (μ
+ α
+). Although the relative proportions of μ
+, α
+, and μ
+α
+ cells fluctuate quite markedly in the serial passages of the tumor, the 3 different subpopulations are consistently observed. The proportion of cells binding fluorescein-labeled anti-μ and rhodamine-labeled anti-α simultaneously in the cytoplasm is slightly higher (+IgA
- 1.29 cells, suggesting differentiation rather than selective growth as the cause of the change. Cloning of 1.29 cells by the limiting dilution technique yielded only cell lines of IgM
-IgA
+ phenotype. Implantation of 1 such cell line in nude mice produced a tumor that retained this phenotype in successive passages.
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M3 - Article
C2 - 6974189
AN - SCOPUS:0019466709
VL - 127
SP - 1388
EP - 1394
JO - Journal of Immunology
JF - Journal of Immunology
SN - 0022-1767
IS - 4
ER -