META-Controlled env-Initiated Transcripts Encoding Superantigens of Murine Mtv29 and Mtv7 and Their Possible Role in B Cell Lymphomagenesis

摘要: Spontaneous germinal center (GC)-derived B cell lymphomas of SJL mice (RCS) transcribe a 1.8-kb Mtv-29 mRNA under control the META- env promoter. The encoded vSAg29 stimulates syngeneic Vβ16 + CD4 T cells, thereby acquiring help necessary for RCS growth. Other strains lymphoma-prone include Mtv29 C57L and MA/MyJ, − Mtv7 -recombinant inbred strain, SW × J-1. these produce similar mouse mtv-vSAg-encoding mRNA, as characterized by Northern blotting, PCR, RNase protection. A in C57L/J MA/MyJ hybridized with an Mtv29- specific oligonucleotide, whereas J-1 produced transcripts hybridizing Mtv7- oligonucleotide. Similar META-env-initiated were absent from LPS-activated cells any strain examined but detected Peyer’s patch RNA mice. Like typical SJL-derived RCS, all stimulated hybridoma cells. Immunohistochemical staining primary tumors showed presence peanut agglutinin binding (PNA ) highly mitotic lymphoblasts, suggesting their GC derivation. findings indicate that this novel is present several strains. Additionally, first description ability to are controlled spliced identically those expressed J-1, I-A s+ , also stimulate Our results suggest important role mtv-vSAgs stimulation development GC-derived murine lymphomas.