New hapten-protein conjugation method using N-(m-aminobenzoyloxy) succinimide as a two-level heterobifunctional agent: thyrotropin-releasing hormone as a model peptide without free amino or carboxyl groups

The use of a two-level heterobifunctional agent N-(m-aminobenzoyloxy)succinimide (m-ABS) allowed us to develop a new method for preparing hapten-protein conjugates. This was demonstrated by a conjugation between thyrotropin-releasing hormone (TRH) and bovine or human serum albumin (BSA or HSA). The conjugation is based on the principle that the succinimidyl ester group of m-ABS immediately acts on an epsilon-amino group of lysine residues of carrier protein BSA (or HSA) and a m-aminobenzoyl group incorporated into the protein is then activated by diazotization to a functional m-diazobenzoyl group (m-DB) acting on a histidyl group of TRH. The TRH-BSA containing about 3.5 mol of TRH per BSA molecule, elicited the production of TRH antibody in rabbits. A new type of enzyme-linked immunosorbent assay (ELISA) for TRH was developed using the antiserum, the solid-phase antigen TRH-HSA and the commercially available horseradish peroxidase-labeled goat anti-rabbit IgG/Fab' as a marker, revealing that the ELISA was monospecific to the hormone and measured as low as 50 pg of the hormone reproducibly. Also, using the antiserum by the indirect immunoperoxidase method the distribution of immunoreactive TRH in the rat brain was demonstrated in neurons of the paraventricular nucleus and neuronal processes of the median eminence. These results strongly suggested that the use of m-ABS provided a simple and efficient new method for preparing immunogens not only for the previously reported haptens with a primary amino group(s) (J. Immunol. Methods 134 (1990) 227), but also for haptens with an imidazole, phenolic, or indole group(s) in the molecule.

Vascular mineralization in the monkey brain

Mineralization of various degrees was found in the brains of 79 (59%) of 134 cynomolgus monkeys (Macaca fascicularis). There was no age dependency in the incidence or severity, nor were there any abnormalities in growth, weight gain, or neurologic signs, although a slight sex difference was observed. The lesions, which were basophilic and intensely positive for periodic acid-Schiff or von Kossa stain, occurred in the vascular walls of the globus pallidus in two types: globoid bodies with prominent concentric lamellar structures in and around the arteriolar and venular wall (type A) and fine granules in the media of small or medium-sized arteries (type B). Electron microscopic examination revealed dense deposits in the degenerated media of small or medium-sized arteries or the thickened walls of the arterioles. X-ray microanalysis demonstrated the presence of calcium, phosphorus, iron, zinc, magnesium, and aluminum.

Putrescine as a comitogen of epidermal growth factor in rat liver growth

Putrescine can stimulate regeneration of the remnant liver after partial hepatectomy in rats when exogenously administered, but its mitogenic action has not been shown in cultured hepatocytes. To find its action site(s) in the regulation of hepatocyte proliferation, we examined its effect on hepatocyte DNA synthesis in relation to mitogenic action of epidermal growth factor in vitro and in vivo. When putrescine was added to the medium of adult rat hepatocytes in primary culture 36 hr after plating, DNA synthesis at 50 hr induced by addition of epidermal growth factor at 24 hr was significantly enhanced. This enhancement disappeared by removal of epidermal growth factor at the time of putrescine addition. Putrescine added to the medium was taken up in a dose-related manner by hepatocytes, irrespective of the presence of epidermal growth factor, whereas 125I-epidermal growth factor binding to hepatocytes was not affected by addition of putrescine. When rats received epidermal growth factor at 2-hr intervals until 10 hr, 5-bromo-2'-deoxyuridine labeled and mitotic hepatocytes were increased in number at 48 hr with increased hepatic DNA content. These increases were not affected by concomitant administration of putrescine until 10 hr, but significantly enhanced by additional administration of putrescine and epidermal growth factor from 20 to 30 hr. We conclude that putrescine may stimulate proliferation of hepatocytes that have entered the G1-phase of the cell cycle as a comitogen of epidermal growth factor, probably through action at the molecular levels to enhance its mitogenic activity.

[A resected case of pulmonary plasma cell granuloma infiltrating the pericardium]

The patient was a 66-year-old man. An abnormal mass on his chest X-ray was pointed out during a regular check-up in November 1991. He was admitted to our hospital with the chief complaint of productive cough in January 1992. With the diagnosis of lung cancer, right middle and lower lobectomy with lymph node resection and partial resection of the pericardium was carried out. The pathological examination revealed pulmonary plasma cell granuloma infiltrating the pericardium. Postoperative course was uneventful. No recurrence was seen 17 months after operation. As pulmonary plasma cell granuloma is histologically benign, this was a very rare case with extra-pulmonary extension. Up to present, only 8 cases including this case has been reported in the literature. We reviewed these 8 cases.

Purification and characterization of lipoyl-AMP:N epsilon-lysine lipoyltransferase from bovine liver mitochondria

Lipoyl-AMP:N epsilon-lysine lipolytransferase (lipolytransferase) catalyzes the transfer of the lipoyl group from lipoyl-AMP to a lysine residue of the specific enzyme proteins. We have shown previously that the lipoyltransferase activities locate in mitochondria using apoH-protein of the glycine cleavage system as an acceptor of the lipoyl group (Fujiwara, K., Okamura-Ikeda, K., and Motokawa, Y. (1990) J. Biol. Chem. 265, 17463-17467). Here we describe the purification and the characterization of two isoforms of lipolytransferase termed lipoyltransferase I and lipoyltransferase II from bovine liver mitochondria. Lipoyltransferase II was purified to apparent homogeneity, whereas the final product of lipoyltransferase I still contained a minor contaminant. Although the two forms could be resolved on a hydroxylapatite column chromatography, they were indistinguishable, as judged by: (a) behavior during purification on ion exchange, hydrophobic, or affinity columns; (b) molecular mass determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel exclusion chromatography (40 kDa); and (c) catalytic properties (substrate specificity, kinetic constants, and optimal pH). Both lipoyltransferase I and II could not use lipoic acid plus MgATP as a substrate in place of lipoyl-AMP. Surprisingly, the lipoyltransferases transferred not only the lipoyl group but also the acyl groups from hexanoyl-, octanoyl-, and decanoyl-AMP to apoH-protein to a similar extent.

Promotional effects of azathioprine on peripheral B cell lymphomas in BALB/c mice induced by administration of 7,12-dimethylbenz[a]anthracene

BALB/c mice either were injected subcutaneously with 25 micrograms/g or 50 micrograms/g body weight 7,12-dimethyl-benz[a]anthracene (DMBA) at the age of 13 weeks, or received repeated s.c. injections of azathioprine (0.1 mg/g) starting from the age of 6 or 18 weeks, or they received treatments with both agents. Of the 317 mice treated, 69 developed lymphomas by the age of 50 weeks. None of the 31 non-treated mice developed lymphomas during this period. The lymphomas, classified according to Pattengale-Taylor's classification for murine lymphomas/leukemias, were examined immunohistochemically and immunogenetically. The lymphomas induced with DMBA showed a male preponderance and a higher incidence of the B cell type, especially in the lymph node and spleen. Azathioprine induced predominantly T-lymphoblastic lymphomas in the thymus and these were found more frequently in females. Treatment with both DMBA and azathioprine remarkably increased the incidence of B lymphomas, especially follicular center cell lymphomas in the spleen, which are the predominant type of spontaneous lymphomas occurring in older BALB/c mice. Some of the treated mice also developed prelymphomatous lesions.

Immunohistochemical distribution of CD44 and desmoplakin I & II in Hailey-Hailey's disease and Darier's disease

The cell-surface glycoprotein CD44 is found on a wide variety of cells including epidermal cells. It is involved in cell to cell adhesion. Desmoplakin I & II are important components of the attachment plaque of desmosomes. In this study, we compared the distribution patterns of anti-CD44 and anti-desmoplakin I & II in Hailey-Hailey's disease and Darier's disease. In the normal skin, anti-CD44 stained the entire periphery of epidermal keratinocytes while anti-desmoplakin I & II produced dotted staining patterns along the periphery of epidermal keratinocytes. In Hailey-Hailey's disease and Darier's disease, the staining pattern of anti-CD44 on acantholized keratinocytes did not change, but anti-desmoplakin I & II lost their peripheral, dotted patterns and stained diffusely in the cytoplasm in most acantholytic cells. These results suggest that, in Hailey-Hailey's disease and Darier's disease, CD44 may be intact even in acantholytic cells but abnormalities of desmoplakin exist in such cells.

Evidence that impaired intracellular collagen synthesis reduces proliferation in cultured rat hepatocytes

Contribution of collagen to cell proliferation was studied in cultured hepatocytes. When alpha,alpha'-dipyridyl, an iron chelator which blocks hydroxylation of prolyl and lysyl residues of procollagen and expression of procollagen mRNA, was added to the medium of rat hepatocytes in primary culture, DNA synthesis of the cells was reduced in a dose-related manner without changes in protein synthesis. The reduction of collagen synthesis was parallel with the changes of DNA synthesis. The addition of P-1894B or minoxidil, which inhibits specifically prolyl hydroxylase or lysyl hydroxylase, respectively, also produced similar results. However, the DNA synthesis was not affected by beta-aminopropionitrile fumarate, which inhibits cross linking in extracellular collagen maturation, nor by purified bacterial collagenase. Intracellular processing of collagen synthesis may be required for proliferation in cultured rat hepatocytes.

Metaphase and anaphase in the artificially induced monopolar spindle

By using monopolar spindles artificially induced in sea urchin embryos, we examined whether or not the presence of two opposing poles was an indispensable condition for keeping chromosomes at a fixed distance from the pole at metaphase and for the anaphase chromosome movement. Chromosomes were stained with Hoechst dye 33342 and their behavior was followed in the monopolar and the control bipolar spindles. In the monopolar spindle, chromosomes were first arranged on a curved metaphase plate and then spread on a part of the imaginary surface of a sphere whose center was the monopole. The estimated chromosome-to-pole distance was similar to that of bipolar spindles at metaphase and remained fixed until chromosomes started to move toward the pole. The average duration of metaphase in the monopolar spindle was 6 times longer than that in the bipolar spindle. The poleward movement of chromosomes in the monopolar spindle was similar to the anaphase A (chromosome-to-pole movement) in the bipolar spindle with respect to the velocity, duration, distance, and synchronization of migration. These results show that even half of the normal spindle has capacities for the arrangement of chromosomes at metaphase and for the anaphase A chromosome movement. Based on these results, we were able to exclude some existing theories of metaphase, such as the one based on the balance of forces between the two poles.

[A case of paraventricular anaplastic astrocytoma following radiation therapy for craniopharyngioma]

A 20-year-old man received 60 Gy of radiation therapy after partial removal of craniopharyngioma. The patient had been well and follow-up CT scans did not show any aggravation for 16 years. Since his activity gradually diminished, he underwent an MRI at the age of 36 which revealed an abnormal mass on the corpus callosum. The mass lesion progressively enlarged thereafter, and was diagnosed as anaplastic astrocytoma by a stereotactic biopsy. He was treated with interferon, however, died at the age of 37. Review of literature disclosed 19 other cases of glioma following radiation therapy for sellar/parasellar tumors. Characteristic features of these cases included 1) lowness of age compared to common glioma cases, 2) tendency to be malignant, 3) tendency to occur in areas where significant doses of radiation had been received previously.

An evaluation of polyamine immunocytochemistry using immunocytochemical model systems

Polyamine (PA) immunocytochemistry (ICC) was evaluated by a recently developed enzyme-linked immunosorbent assay (ELISA) binding test (ELISABT) using an anti-spermine (Spm) serum raised against Spm conjugated via the cross-linker N-(gamma-maleimidobutyryloxy)succinimide (GMBS) with bovine serum albumin. In the test the antiserum showed strong immunoreactivity with N1-acetylspermine (Ac-Spm) and acetylspermidine (N1-Ac-Spd and N8-Ac-Spd), and low immunoreactivity with Spm and Spd, which was, however, markedly enhanced after reaction with GMBS, acetic anhydride or glutaraldehyde. Complete agreement with results of immunoblot analysis was observed. PA-like immunoreactivity observed in the present PA ICC in cells in the foveolae and isthmus of rat gastric glands was completely abolished by absorption of the serum with N1,N12-diacetyl-Spm, Ac-Spm or N1-Ac-Spd, but not by Spm or Spd. This absorption test was then simulated by an ELISA inhibition test (ELISAIT) with a solid phase conjugated with Ac-Spm or Spm, and by a PA ICC model system using Sepharose gel beads conjugated with each of several PAs. The results strongly suggest that the immunostaining in the gastric mucosa was mainly due to antibody species in the serum specific to 'acylated' Spm and Spd, but not to Spm or Spd. Acetyl PAs exist at such low concentrations in animal tissues that they are virtually undetectable by current ICC methods. Therefore Spm and Spd are likely candidates for those detected, after having been converted by fixation into such PA derivatives as become reactive with the antiserum.

Significant increases in serum CA125 and CA19-9 following torsion from an adenofibroma of the ovary: a case report

Significant increases in the serum levels of cancer antigen 125 (CA125) and carbohydrate antigen 19-9 (CA19-9) were observed over one month prior to the removal of an ovarian adenofibroma. The serum levels of CA125 and CA19-9 decreased rapidly after surgery. The surface of the tumor at surgery showed marked inflammation, probably induced by the necrosis produced by torsion. Pathologically, most of the tumor was necrotic, and histoimmunochemical staining of the viable cells was weak for CA125 but intense for CA19-9. Clinicopathological observations of the case suggested that CA125 and CA19-9 might be stimulated in the cells by inflammation or that originally existing CA125 and CA19-9 were released from the tumor cells following the cell necrosis.

Fat-storing cell abnormalities associated with endothelial cell damage after cold ischemic storage of rat liver in UW solution

Rat liver was stored at 1 degree C in University of Wisconsin solution, and morphological changes were observed after 12, 18, 24, and 36 hr by transmission electron microscopy. There were two types of endothelial cell damage in the hepatic sinusoids. One was disruption of the endothelial linings, and the other detachment of endothelial cells into the sinusoidal space accompanied by fat-storing cell abnormalities. The former damage was seen after storage longer than 12 hr, while the latter developed after 18 hr even in the hepatic sinusoids with no disruption of the linings. Considering that fat-storing cell damage can produce endothelial cell destruction, this damage should be given attention as one of factors of endothelial cell destruction in the hepatic sinusoids after cold storage of the liver.

Development and application of an enzyme immunoassay for karasurin A, an effective protein component of Trichosanthes kirilowii Max. var. japonicum Kitam

A method was developed for specific estimation of the content of a non-enzymatic protein, karasurin A, in fractions taken during the extraction and purification processes from a natural source. Anti-karokon serum was elicited in rabbits immunized with fragments of karokon, a dried root tuber of Trichosanthes kirilowii Max. var. japonicum Kitam. Rabbit antibody specific for karasurin A was identified in anti-karokon serum by the Western blotting method. After separation by SDS-PAGE, protein bands of purified karasurin A and extracted proteins from a medicinal herb which is a karasurin A source were reacted with anti-karokon serum followed by treatment with horseradish peroxidase (HRP)-labeled Fab' of goat anti-rabbit IgG, and then bound HRP-labeled second antibody on protein bands was developed to brown by reaction with a substrate solution of the used enzyme. A novel selected antibody enzyme immunoassay (SAEIA) for karasurin A was developed using selective binding of anti-karasurin A antibody in anti-karokon serum to solid phase karasurin A and HRP-labeled Fab' of the second antibody as the tracer. Specific estimation of the content of karasurin A in several fractions taken during the isolation and purification processes of the protein were possible using the SAEIA method.

Immunoglobulin class switch of anti-ganglioside monoclonal antibody from IgM to IgG

Ganglioside GM2, which is one of the major gangliosides expressed on cell surface of neuroectodermal-origin human tumors, has been focused on as a target molecule for passive immunotherapy. One of the problems in this area was that monoclonal antibodies (mAbs) raised against GM2 were of IgM class even if donors of B cells were varied in mouse, rat or human. We stimulated two kinds of mice hybridomas having membrane-bound anti-GM2 IgM on their surface with GM2 incorporated in synthetic liposomes in the presence of the mouse thymocytes to accelerate the class switch of immunoglobulins (Igs). After the stimulation, protein A-reactive clones were sorted out using a cell sorter. We finally isolated two class switch variants generating mouse IgG3, designated KM796 and KM750, from original hybridomas producing mouse IgM anti-GM2 mAbs, KM696 and KM697, respectively after over 20-time repetitions of the sorting. ELISA with 11 common gangliosides revealed that one of the variant, KM750, retained the same binding specificity to N-acetyl GM2 as that of the parental IgM, KM697. By ELISA using panel of anti-idiotype (Id) mAbs to anti-GM2 mAbs, KM750 was shown to retain the parental KM697 Id. Another variant KM796 almost lost its activity in purification process in acidic condition and changes in Id were suggested. In immunofluorescence assay, KM750 was confirmed to bind to GM2-expressing tumor cell lines. The class switch hybridoma has been stably cultured with the production of the IgG3-class mAb for more than 22 months.

Protective action of putrescine against rat liver injury

The hepatoprotective action of orally dosed putrescine was investigated using rat models of liver injury. When rats received putrescine orally soon after a dose of carbon tetrachloride or D-galactosamine, deranged serum alanine aminotransferase values and prothrombin times were significantly attenuated compared with control levels, with improved histologic extent of liver injury. Putrescine addition to the medium of rat hepatocytes in primary culture reduced cell killing induced by D-galactosamine or the membrane detergents chenodeoxycholic acid and Triton X-100. Similar reduction was seen in cells exposed to tert-butyl hydroperoxide (TBHP), an agent producing cell death through lipid peroxidation, with attenuation of cellular malondialdehyde content. Putrescine also significantly attenuated the extent of increased plasma membrane microviscosity as assessed with 1-[4-(trimethylammonio)phenyl]-6-phenyl-1,3,5-hexatriene in TBHP-treated cells. These results suggest that orally given putrescine protects against liver injury. Plasma membrane stabilization and reduction of lipid peroxidation may contribute to this hepatoprotection.

Intraarterial infusion of autologous lymphocytes for the treatment of refractory lymphoedema. Preliminary report

OBJECTIVE

To evaluate the results of the treatment of lymphoedema by intra-arterial infusion of autologous lymphocytes.

DESIGN

Open study.

SETTING

University Hospital.

SUBJECTS

13 patients with refractory lymphoedema.

INTERVENTIONS

Lymphocytes were separated from the patient's own blood using a blood cell separator; about 100 cc of lymphocyte dominant blood separated from this blood was immediately infused into the proximal artery of the affected limb. Infusion was practiced once a week, and repeated 4 to 6 times.

MAIN OUTCOME MEASURES

Change in size of the affected limb (defined as the difference between the affected limb and the normal limb after treatment), and softening of the edema (measured with a tension gauge).

RESULTS

In all 13 patients there was softening of the affected hard limb followed by a reduction in the size of the limb (mean 64%), and the ache and sensation of heat in the limb lessened. The reduction in size was maintained in 9 of the 13 patients for three months, despite returning to their normal activities.

CONCLUSION

Intra-arterial infusion of autologous lymphocytes is a promising treatment for refractory lymphoedema.

Specificity of trypsin digestion and conformational flexibility at different sites of unfolded lysozyme

Fourteen tryptic peptides and nine intermediates were identified as products of trypsin digestion of reduced and S-3-(trimethylated amino) propylated lysozyme. Kinetics of the appearance and disappearance of these products were observed by monitoring the peak areas on the chromatogram. In spite of the complicated reaction pathways, kinetics of the digestion of proteins and several intermediate products show simple decay curves with a single rate constant. In this paper, the trypsin susceptibility of the individual cleavage site is defined as a hydrolytic rate constant of the susceptible peptide bond in the presence of 10 nM trypsin. The cleavage sites of unfolded lysozyme are classified into two groups in terms of the trypsin susceptibility: one has a high susceptibility (10-20 h-1) and the other a low susceptibility (1.0-2.0 h-1). In the unfolded state of lysozyme, in conclusion, the region from residues 15 to 61 has a strong resistance to trypsin digestion; on the other hand, the C-terminal half of the polypeptide chain is flexible enough to fit into the active site of trypsin. In addition, six kinds of pentapeptides were synthesized as analogues of lysozyme fragments including Arg 14, Arg 21, Lys 33, Arg 45, Arg 61, and Arg 73. Kinetics of tryptic digestion of them were observed. Both kcat and KM were determined for these synthetic pentapeptides. The susceptibility of each cleavage site in pentapeptides is determined and compared with that corresponding in proteins. The susceptibility is usually higher when the susceptible peptide bond is included in proteins than in pentapeptides, so long as the conformation of peptide chain is flexible. However, susceptibilities of a few sites in proteins are lower than those in pentapeptides. This means that the peptide chains tend to fold locally to prevent trypsin from binding to the sites. It was found that the sites of Arg 21 and Arg 45 are indeed resistant to trypsin, but the site of Lys 33 is not so much, although the hydrolytic rate at Lys 33 itself is extremely slow.

[Phase I study of CGS16949A--a new aromatase inhibitor. Cooperative Study Group for CGS16949A]

Phase I study of CGS16949A--a new aromatase inhibitor--was performed in postmenopausal women with advanced breast cancer who received either single oral administration of 4 and 8 mg, or multiple oral daily administration of 1, 2, 4, 8 and 16 mg for 5.5 days. No side effects were observed after single dose administration of 4 mg and 8 mg of CGS16949A. In the multiple administration, one patient received 1 mg/day for 3 days complained of abdominal pain (Grade 2), but administration of CGS16949 A was continued despite of the pain. In order to assess the causal relationship of the drug with the abdominal pain, the number of patients in 1 mg/day group was doubled from 3 to 6 patients, but no side effects were observed in the remaining five patients. In addition, no side effects, including abdominal pain, were noted in the other 2, 4, 8 and 16 mg/day groups. After multiple administration, plasma concentrations of estradiol at 5 hrs after the final dosage in the respective dose groups were reduced to 47.1 +/- 8.3%, 37.3 +/- 3.0%, 28.0 +/- 7.8%, 26.0 +/- 11.3% and 26.6 +/- 13.8% respectively. Similar tendencies were observed in estrone plasma levels and urinary estrogens levels. In this study, the reduction of plasma estrogen levels was confirmed following administration of CGS 16949A. The clinical usefulness of this new aromatase inhibitor remains to be studied further.

Effect of omentopexy on wound healing of the extensively detached and anastomosed canine trachea

BACKGROUND

To examine the beneficial effect of omentopexy for tracheal anastomosis after extensive detachment that may cause impairment of the blood supply, the time course of tracheal wound healing was studied experimentally.

METHODS

Circumferential resection of the trachea for three cartilage rings (nos. 11, 12, 13) and end-to-end anastomosis of the trachea were performed in 66 mongrel dogs, which were allocated to three groups (n = 22 in each). In the detached group, the trachea was entirely mobilized and isolated from the surrounding tissue for a length of 25 cartilage rings. In the wrapped group, omentopexy was added for the anastomosed site. In the control group, the same anastomosis was performed without omentopexy or detachment. The tracheal tissue blood flow was measured with a laser Doppler flow meter at the anastomosed site, and the tensile strength was determined with a tensiometer.

RESULTS

All groups showed significant decreases in the blood flow on day 3, compared with the preoperative values, and increases stepwise from day 7 to day 21. On days 3, 7, and 14 the tissue blood flow was significantly (p < 0.01) higher in the wrapped group than in the detached group, although on day 21 it did not differ significantly among the three groups. The tensile strengths of the cartilaginous and membranous portions were significantly (p < 0.05) higher in the wrapped and control groups than in the detached group. On day 21, no significant intergroup differences were observed for this parameter. In the wrapped group and in the control group, the capillary network at the anastomosed site was well developed on day 7, and the tracheal mucosal epithelium was well regenerated on day 21 without granulation formation.

CONCLUSIONS

This study showed that omentopexy at the anastomosed site of an extensively detached trachea provided adequate wound healing caused by rapid recovery of the tissue blood flow.

Regulating factors of liver regeneration after hepatectomy

The factors regulating liver regeneration were studied by measuring changes in the liver volume and serum hepatocyte growth factor (HGF) levels after hepatectomy. Changes in the liver volumes were studied in 68 hepatectomized patients, including (A) hepatoma patients who had chronic hepatitis or liver cirrhosis (n = 44) and (B) metastatic liver cancer patients who had normal liver parenchyma (n = 24). The hepatic volume increased by 13.8% of the remnant hepatic volume in group A and by 49.1% in group B. The examined factors included the percentage of resected liver volume (%RLV) and the results of laboratory tests. Regression analysis showed that in group A, both %RLV (beta = 0.46) and the serum total bilirubin (T-Bil) level (beta = -0.33) correlated significantly with the extent of liver regeneration and that in group B, only %RLV (beta = 0.78) correlated significantly with the regeneration. Serum HGF levels after hepatectomy were studied in 21 hepatectomized patients, including 11 hepatoma patients and 10 patients with some types of metastatic liver cancer. Serum HGF levels increased significantly after surgery in all 21 patients. Regression analysis, however, showed that the change in HGF was related to liver cirrhosis (beta = 0.46) and to the maximal postoperative T-Bil level (beta = 0.51) but not to the extent of liver regeneration after hepatectomy. These results suggest that liver regeneration is regulated primarily by factors relating to the percentage of the resected liver parenchyma and that serum HGF levels do not directly relate to liver regeneration after surgery.