1988 Fiscal Year Final Research Report Summary
Studies on the physiological and pathological roles of Serum Thymic Factor in blood and thymus for clinical application.
| Project/Area Number |
60440064
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Thoracic surgery
|
|---|
| Research Institution | Nagoya City University |
|---|
Principal Investigator |
MASAOKA Akira Nagoya City University, school of medicine,Professor, 医学部, 教授 (10028326)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
YAMAKAWA Yohsuke Nagoya City Univ.,school of medicine,Assistant, 医学部, 助手 (40148284)
SHIBATA Kazuo Nagoya City Univ.,school of medicine,Assistant, 医学部, 助手 (20145733)
HASHIMOTO Takahiko Nagoya City Univ.,school of medicine,Assistant Professor, 医学部, 助教授 (00080094)
YANAIHARA Noboru Shizuoka Preferectural Univ.,school of pharmacology,Professor, 薬学部, 教授 (80046250)
|
|---|
| Project Period (FY) |
1985 – 1988
|
| Keywords | Serum thymic factor / Porcine serum / Radioimmunoassay / Thymus / Thymoma / Synthetic serum thymic factor / 放射免疫測定法 |
|---|
| Research Abstract |
The serum thymic factor(STF) is a nonapeptide initially isolated from porcine serm, but its true origin in the body has not yet been determined.
In an attempt to ascertain whether the presence of STF is restricted to the thymus, and to evaluate STF levels in the serum in various clinico-immunological conditions, we established a STF-specific radioimmunoassay as a substitute for the conventional indirect bioassay, and investigated the distribution and the chromatographic behavior of STF-like immunoreactivity in porcine plasma and various tissues, and in human plasma, thymus and thymoma.
The standard STF was synthesized according to its amino acid sequence, and C-terminal-specific anti-synthetic STF(R0116-5) was raised in rabbits against synthetic STF-BSA conjugate. The radioimmunoassay was sensitive to the synthe-tic STF in the range from 0.6pg to 640pg, and any cross-reactivity with other peptides was not detected.
In porcine plasma, the level of immunoreactive STF(IR-STF) was 32 5pg, whilst in healthy human plasma, the values were always below the minimal detectable level. The IR-STF was detected in the extracts of porcine thymus, liver, kindney and spleen, and levels in the liver and kidney were 2 to 3 times as high as in the thymus. In the human thymus and thymoma, with or without myasthenia gravis, levels were relatively high.
Gel filtration and HPLC reveled the presence of the larger molecular weight components in the IR-STF in all porcine and human tissues examined. Tripsinization of these components brought them to convert to a substance which corresponded closely in its elution on gel filtration and HPLC to that of syn-thetic STF.
Thus itis conceivable that STF is not a thymus-specific peptide, and the majo-rity of STF may exist in the thymus, thymoma,liver, spleen and kidney in a form of larger biosynthetic precursors for STF.
Comparison between STF and thymosin alpha-1 has been in progress.
|
