Abstract: An isoform of the TGF beta receptor II comprising a sequence of about of 80 amino acids and lacking a transmembrane domain. The isoform comprises the amino acid sequence set forth in SEQ ID No. 12. The isoform may have the amino acid sequence set forth in SEQ ID No. 2 or sequences having at least 85% sequence identity to the sequence set forth in SEQ ID No. 2. A fusion peptide is provided comprising an isoform of the TGF beta II receptor fused to a ligand, wherein a vector comprising the fusion peptide is used to treat cancer and/or hepatic fibrosis. An antibody binding the soluble isoform of the TGF beta II receptor is provided. The antibody binds the amino acid sequence shown in SEQ ID No. 12 and is used in in vitro methods.

Abstract: A method to determine the activity level of autoimmune diseases, the method including a) to supply a biological sample; b) to determine the TßRII-A, TßRII-B and TßRII-Se isoforms level of the biological sample; c) calculate the activity level by performing the quotient between the TßRII-Se level and the level of the addition of TßRII-A y TßRII-B. The isoforms level are measured by detecting the polypeptides of the isoforms or the mRNA of the isoforms in the isolated circulating mononuclear blood cells by means of, for instance, RT-qPCR. The ?Ct of each splice variants individually showed a correlation with autoimmune disease activity. Additionally, a similar correlation with autoimmune disease activity was obtained when the ?Ct of T?RII-SE was added to the ?Ct of T?RII-A and the ?Ct of T?RII-A.

Abstract: An isoform of the TGF beta receptor II comprising a sequence of about of 80 amino acids and lacking a transmembrane domain; wherein the isoform is a TGF?-1 agonist. The isoform comprises the amino acid sequence set forth in SEQ ID No. 12. The isoform may have the amino acid sequence set forth in SEQ ID No. 2 or sequences having at least 85% sequence identity to the sequence set forth in SEQ ID No. 2.

Abstract: An isoform of the TGF beta receptor II comprising a sequence of about of 80 amino acids and lacking a transmembrane domain; wherein the isoform is a TGF?-1 agonist. The isoform comprises the amino acid sequence set forth in SEQ ID No. 12. The isoform may have the amino acid sequence set forth in SEQ ID No. 2 or sequences having at least 85% sequence identity to the sequence set forth in SEQ ID No. 2.