ABSTRACT
Transcription of HERV-K/HTDV proviruses in various morphological forms of GCTs and in normal testicular parenchyma and placenta was studied by RT-PCR with specific primers discriminating type 1 proviruses from type 2 ones. The results indicate that transcription of type 2 HERV-K/HTDV proviruses takes place and mRNA of protein cORF, coded for only by type 2 proviruses, is synthesized in all malignant germinogenic tumors. In normal testicular tissue and placenta type 1 HERV-K/HTDV proviruses are expressed. No expression of HERV-K/HTDV proviruses was detected in nongerminogenic testicular tumors. Since cORF protein possesses transforming activity, its possible role in the pathogenesis of GCTs is discussed. Generation of humoral immune response to structural HERV-K/HTDV proteins in various morphological forms of GCTs confirmed the possibility of using antibodies to structural HERV-K/HTDV proteins as additional markers of GCTs.
Subject(s)
Endogenous Retroviruses/isolation & purification , Germinoma/virology , Testicular Neoplasms/virology , Animals , Base Sequence , Blotting, Western , Cell Line , DNA Primers , DNA, Complementary , Endogenous Retroviruses/genetics , Female , Fluorescent Antibody Technique, Indirect , Humans , Male , Open Reading Frames , Placenta/virology , Reverse Transcriptase Polymerase Chain Reaction , Testis/virologyABSTRACT
Simultaneous measurements of arterial and venous plasma "immunoreactive" angiotensin II and angiotensin II peptide fragments (octapeptide, heptapeptide, hexapeptide, and pentapeptide), done with high performance liquid chromatography and radioimmunoassay, were obtained in nine human subjects. Results indicate that the angiotensin II octapeptide is the major peptide fragment in both arterial and venous plasma. Approximately 80% of the "immunoreactive" angiotensin II measured in both arterial and venous plasma is the angiotensin II octapeptide fragment. The concentration of angiotensin II octapeptide in venous blood approximated the concentration of angiotensin II octapeptide measured in arterial blood. These data suggest that venous concentrations of angiotensin II octapeptide probably reflect the activity of the tissue renin angiotensin system, because its concentration was much higher than would be predicted from inactivation of arterial blood angiotensin II octapeptide in peripheral tissues.
Subject(s)
Angiotensin II/blood , Peptide Fragments/blood , Adult , Aged , Aged, 80 and over , Blood Specimen Collection , Chromatography, High Pressure Liquid , Female , Humans , Male , Middle Aged , RadioimmunoassayABSTRACT
A highly selective high-performance liquid chromatographic-radioimmunoassay method for the measurement of individual endogenous angiotensin peptides in human plasma is described. This method allows the complete resolution of the immunoreactive angiotensin II peptides. We have also measured the angiotensin peptide levels and compared them in both pooled and individual human plasma. The effects of inhibition of angiotensin-converting enzyme on the angiotensin peptide levels have also been observed in a patient with renovascular hypertension with the plasma angiotensin II level being reduced greater than seven-fold. This new methodology was validated by recovery experiments in plasma over a range of physiological levels using two methods of detection, radioimmunoassay and liquid scintillation counting. Consistent recoveries near 80% have been achieved for each peptide in plasma at concentrations over a physiological range. The described method enables the direct measurement of the circulating angiotensin peptides and the elucidation of their specific roles in physiological and disease states.