An automated rapid detection system using the quenching probe method for detecting interleukin 28B and inosine triphosphatase single nucleotide polymorphisms in chronic hepatitis C.

Single nucleotide polymorphisms (SNPs) in the interleukin 28B gene (IL28B) are good pretreatment predictors of anti-hepatitis C virus (HCV) therapy with interferon. SNPs of the inosine triphosphatase (ITPA) gene are associated with reduced haemoglobin levels during treatment with ribavirin. The i-densy™ (Arkray, Inc.), which is based on the quenching probe (QP) method, automatically detects target genes in blood samples by fluorescence quenching within 100 min. Using a QP and primer set, a gene amplification response is generated that can quickly and easily detect a specific gene's arrangement by fluorometry. The present study was conducted to compare the utility of i-densy (QP method) with that of conventional direct sequencing (DS) for detecting SNPs in the IL28B and ITPA genes in chronic hepatitis C patients. Between June 2011 and January 2012, 73 consecutive patients underwent genotyping of IL28B, and 54 patients underwent genotyping of ITPA. All of the patients were seropositive for HCV-RNA. The IL28B and ITPA genotypes were tested for bi-allelic polymorphisms in rs8099917 (T/T, T/G and G/G; minor allele, G) and rs1127354 (C/C, C/A and A/A; minor allele, A), respectively. The results obtained with the QP method were identical to those obtained with the conventional DS method. The frequency of the IL28B genotypes TT, GT and GG were 74%, 24.7% and 1.4%, respectively, and those of the ITPA genotypes CC, AC and AA were 68.5%, 29.6% and 1.9%, respectively. These results indicate that the i-densy using the QP method can automatically, quickly and easily identify genotypes of IL28B and ITPA.

Expression of Ley antigen in human immunodeficiency virus-infected human T cell lines and in peripheral lymphocytes of patients with acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC).

Ley determinant (Fuc alpha 1----2Gal beta 1----4[Fuc alpha 1----3]GlcNAc beta 1----R) defined by mAb BM-1 is highly expressed in human immunodeficiency virus (HIV)-infected T cell lines and in CD3+ peripheral mature T cells of patients with acquired immune deficiency syndrome (AIDS) or with AIDS-related complex (ARC). Ley expression increased greatly in the CD3+ population in the advanced stage of AIDS when the CD4+ population decreased greatly. Six other carbohydrate antigens tested by their respective mAbs were not detected in these same cells. None of the carbohydrate antigens tested by the seven mAbs used in this study were found in noninfected T cell lines and in normal peripheral blood lymphocytes.

Retrospective and prospective studies of hepatitis B virus reactivation in malignant lymphoma with occult HBV carrier.

BACKGROUND: In surface antigen of hepatitis B virus (HBsAg)-positive carrier for anticancer treatment of malignant lymphoma, it is well recognized that reactivation of hepatitis B virus (HBV) occasionally occurs. However, there have been only a few studies of HBV reactivation in serum HBsAg-negative and hepatitis B core antigen (HBcAb)-positive occult HBV carriers. We looked at both retrospective and prospective studies to determine the prevalence, clinical course and risk factor of HBV reactivation during chemotherapy in lymphoma patients. PATIENTS AND METHODS: Forty-eight of 127 (37.8%) lymphoma patients were HBsAg negative and HBcAb positive, and 24 of these patients were then given liver function tests and HBsAg tests monthly and serum HBV DNA every 3 months. RESULTS: HBV reactivation was observed in two patients (4.1%) who had received intensive chemotherapy including steroid and rituximab. Immediate administration of entecavir therapy after elevation of HBV DNA level was conducted, and this resulted in reduction of it and improvement of liver function test. CONCLUSIONS: Rituximab plus steroid-containing regimens may increase the risk of HBV reactivation in HBsAg-negative and HBcAb-positive lymphoma patients. More ambitious prospective studies are required to establish clinically useful or cost-effective follow-up methods for control of HBV reactivation in lymphoma patients with occult HBV infection.

Involvement of programmed cell death 4 in transforming growth factor-beta1-induced apoptosis in human hepatocellular carcinoma.

The programmed cell death 4 (PDCD4) gene was originally identified as a tumor-related gene in humans and acts as a tumor-suppressor in mouse epidermal carcinoma cells. However, its function and regulatory mechanisms of expression in human cancer remain to be elucidated. We therefore investigated the expression of PDCD4 in human hepatocellular carcinoma (HCC) and the role of PDCD4 in human HCC cells. Downregulation of PDCD4 protein was observed in all HCC tissues tested compared with corresponding noncancerous liver, as revealed by Western blotting or immunohistochemical staining. Human HCC cell line, Huh7, transfected with PDCD4 cDNA showed nuclear fragmentation and DNA laddering characteristic of apoptotic cells associated with mitochondrial changes and caspase activation. Transforming growth factor-beta1 (TGF-beta1) treatment of Huh7 cells resulted in increased PDCD4 expression and occurrence of apoptosis, also concomitant with mitochondrial events and caspase activation. Transfection of Smad7, a known antagonist to TGF-beta1 signaling, protected cells from TGF-beta1-mediated apoptosis and suppressed TGF-beta1-induced PDCD4 expression. Moreover, antisense PDCD4 transfectants were resistant to apoptosis induced by TGF-beta1. In conclusion, these data suggest that PDCD4 is a proapoptotic molecule involved in TGF-beta1-induced apoptosis in human HCC cells, and a possible tumor suppressor in hepatocarcinogenesis.

Antisense oligonucleotides directed against the viral RNA polymerase gene enhance survival of mice infected with influenza A.

We have investigated the ability of antisense phosphorothioate oligonucleotides to enhance the survival of mice infected with influenza A virus. The oligonucleotides were complementary to sequences surrounding the translation initiation codons of the viral PB2 or PA genes (PB2-as or PA-as, respectively) of the influenza A virus RNA polymerases. Intravenous administration of PB2-as in a complex with a cationic liposome, Tfx-10, significantly prolonged the mean survival time in days and increased overall survival rates of mice infected with the influenza A virus. Liposomally encapsulated PB2-as inhibited viral growth in lung tissues and reduced pulmonary consolidations. Liposomally encapsulated PB2-as could be an effective therapeutic agent against influenza A virus.

Involvement of the Ets-1 gene in overexpression of matrilysin in human hepatocellular carcinoma.

Although matrix metalloproteinases (MMPs) are thought to be involved in the invasion and metastasis of a variety of malignant tumors, including human hepatocellular carcinoma (HCC), the mechanisms for the expression of MMPs in HCC are not known. To understand the mechanism(s) of MMP expression, the expression of matrilysin (MMP-7) and several genes of the Ets transcription factor family was investigated in human HCC and hepatoma-derived cell lines. The role of Ets-1 gene expression in HCC was also studied. Analysis by semiquantitative reverse transcription-PCR revealed that MMP-7 and Ets-1 are overexpressed and closely associated in HCC. To clarify the role of Ets-1, hepatoma cells were transduced with human Ets-1 or targeted with the Ets-1-specific antisense oligonucleotides. Cells stably transduced with the Ets-1 gene showed increased MMP-7 expression compared to parental and mock-transfected cells. Cells targeted with Ets-1-specific antisense oligonucleotides showed reduced expression of MMP-7. Cotransfection of cells with a MMP-7 promoter-reporter gene plasmid and an Ets-1 expression vector yielded an increase in MMP-7 promoter activity in an Ets-1-responsive element-dependent manner. Taken together, these data suggested that the Ets-1 oncogene is up-regulated and involved in the overexpression of MMP-7 in human HCC and may contribute to the progression of HCC.

Gene structure and quinol oxidase activity of a cytochrome bd-type oxidase from Bacillus stearothermophilus.

Gram-positive thermophilic Bacillus species contain cytochrome caa3-type cytochrome c oxidase as their main terminal oxidase in the respiratory chain. We previously identified and purified an alternative oxidase, cytochrome bd-type quinol oxidase, from a mutant of Bacillus stearothermophilus defective in the caa3-type oxidase activity (J. Sakamoto et al., FEMS Microbiol. Lett. 143 (1996) 151-158). Compared with proteobacterial counterparts, B. stearothermophilus cytochrome bd showed lower molecular weights of the two subunits, shorter wavelength of alpha-band absorption maximum due to heme D, and lower quinol oxidase activity. Preincubation with menaquinone-2 enhanced the enzyme activity up to 40 times, suggesting that, besides the catalytic site, there is another quinone-binding site which largely affects the enzyme activity. In order to clarify the molecular basis of the differences of cytochromes bd between B. stearothermophilus and proteobacteria, the genes encoding for the B. stearothermophilus bd was cloned based on its partial peptide sequences. The gene for subunit I (cbdA) encodes 448 amino acid residues with a molecular weight of 50195 Da, which is 14 and 17% shorter than those of Escherichia coli and Azotobacter vinelandii, respectively, and CbdA lacks the C-terminal half of the long hydrophilic loop between the putative transmembrane segments V and VI (Q loop), which has been suggested to include the substrate quinone-binding site for the E. coli enzyme. The gene for subunit II (cbdB) encodes 342 residues with a molecular weight of 38992 Da. Homology search indicated that the B. stearothermophilus cbdAB has the highest sequence similarity to ythAB in B. subtilis genome rather than to cydAB, the first set of cytochrome bd genes identified in the genome. Sequence comparison of cytochromes bd and their homologs from various organisms demonstrates that the proteins can be classified into two subfamilies, a proteobacterial type including E. coli bd and a more widely distributed type including the B. stearothermophilus enzyme, suggesting that the latter type is evolutionarily older.

Congenital muscular dystrophy with primary partial laminin alpha2 chain deficiency: molecular study.

The authors report a case of congenital muscular dystrophy with mild nonprogressive muscle weakness, white matter hypodensity, and absence of the laminin alpha2 chain in muscle fibers with two antibodies, but not with four others. They identified mutations in LAMA2, which explain the partial laminin alpha2 deficiency. Analysis of this case and two others allows us to refine the epitopes of two of the commercial antibodies, and illustrate the importance of using antibodies directed against different domains of the protein.

Nitric oxide production by bronchoalveolar cells during allograft rejection in the rat.

BACKGROUND: We reported the increased nitric oxide (NO) level in exhaled air of rat lung transplant recipients during acute rejection (AR). The aim of this study was to determine the site and level of NO production in the rejected graft. METHODS: Rat lung transplantation was performed in isografts and allografts. RESULTS: In isografts, no AR and no significant increase in NO production was identified. In allografts, grades I-II of AR was seen on postoperative day (POD) 3 and grade III on POD 5. NO produced by BAL cells increased on both POD 3 (11.8+/-2.0 parts per billion [ppb]) and POD 5 (115.3+/-66.9 ppb). There was a highly significant correlation between the level of NO and the severity of AR (p=0.862, P<0.005). BAL cells from allografts expressed iNOS mRNA. Among them, macrophages, lymphocytes and neutrophils were immunostained for iNOS. CONCLUSION: NO produced by BAL cells was detected in the early stages of rejection. Therefore, it may serve as a sensitive indicator of AR in lung transplantation.

Enhancement of the interleukin 2 receptor expression on T cells by multiple B-lymphotropic lymphokines.

Three new human lymphokines, interleukin-5, BSF-2 and BSF-MP6, were shown to be active in the enhancement of the IL-2 receptor expression on T cells, although they do not stimulate growth of the T cells.

Simplified rat lung transplantation using a cuff technique.

A cuff technique is introduced to anastomose pulmonary vein and pulmonary artery in rat lung transplantation. In 11 consecutive cases, the average graft ischemic time was 13.5 +/- 2.0 minutes and operating time 100.7 +/- 4.8 minutes: The time for ischemia was less than one third of previous reports and the time for operation one half of previous reports. Excluding two operative deaths, the survival rate was 88.8% (8/9) on postoperative day 11, when contralateral pneumonectomy revealed excellent graft function supporting the oxygenation of the animals.

Single lung transplantation in rats with chemically induced pulmonary hypertension.

Physiologic effects of single lung transplantation on pulmonary hypertension were studied in rats with monocrotaline-induced pulmonary hypertension. Inbred rats treated with monocrotaline (40 mg/kg) received a left lung isograft from a normal donor 2 weeks later, when pulmonary hypertension became significant (transplant group; n = 6). These rats and control rats treated with monocrotaline (mediated control group; n = 11) or vehicle alone (normal control group; n = 9) were followed up weekly by metabolic treadmill testing for exercise tolerance and oxygen consumption up to 6 weeks after monocrotaline (4 weeks after transplantation), when all rats underwent hemodynamic and histologic examinations. Whereas maximal oxygen consumption and exercise tolerance consistently deteriorated in the medicated control group of rats, indices in the transplant group stopped deteriorating 2 weeks after lung transplantation and remained at levels similar to those of normal control rats. Severe pulmonary hypertension (68 +/- 19 mm Hg) and right ventricular hypertrophy (right ventricular/left ventricular weight ratio, 0.95 +/- 0.19) were confirmed in medicated control rats in contrast to transplant animals, in which these two indices remained at normal control levels. Whereas left-to-right lung perfusion ratio was constant among rats not receiving transplants (0.69 +/- 0.16), it was significantly elevated (2.27 +/- 0.65; p less than 0.001) in those receiving transplants, suggesting preferential flow through the lung isograft. The results suggest that, in the early phase of pulmonary hypertension, single lung transplantation shifts pulmonary perfusion to the grafted lung, avoiding right ventricular pressure overload and thereby preserving exercise tolerance at a nearly normal level in rats with monocrotaline-induced pulmonary hypertension.

Single lung transplantation in rats with fatal pulmonary hypertension.

Effects of single lung transplantation on fatal pulmonary hypertension were evaluated in rats receiving a lethal dose of monocrotaline. Inbred rats treated with monocrotaline (80 mg/kg) received a left lung isograft at 4 weeks (n = 9) and at 6 weeks (n = 6), when moderate and severe pulmonary hypertension, respectively, had developed. Medicated (n = 12) and nonmedicated rats (n = 12) served as control animals. Each rat was tested weekly with treadmill for exercise tolerance and oxygen consumption during a 10-week period after medication and after they were killed. Medicated control rats lost exercise tolerance and highest oxygen consumption per unit time consistently to the range of resting value (or 45% of nonmedicated control rats), and all died from severe pulmonary vascular occlusive disease with right ventricular hypertrophy before 10 weeks (right ventricular/left ventricular weight ratio of 1.16). All rats receiving a left lung isograft at 4 weeks survived and regained highest oxygen consumption per unit time (87% of nonmedicated control rats), with the lung transplant receiving 65% (nonmedicated control rats, 39%) of cardiac output and milder right ventricular hypertrophy (right ventricular/left ventricular weight ratio of 0.46). Except for one, all rats that received a left lung isograft at 6 weeks tolerated single lung transplantation, but they died soon after reperfusion because of pulmonary edema in the graft that received 58% of cardiac output with right ventricular/left ventricular weight ratio of 0.79. Results of single lung transplantation in rats were dependent on severity of pulmonary hypertension. In rats with moderate pulmonary hypertension, single lung transplantation was successful in reversing exercise intolerance and right ventricular hypertrophy. Single lung transplantation was unsuccessful when pulmonary hypertension was severe in the rat model because increased flow toward the lung transplant resulted in graft pulmonary edema.

Increased nitric oxide levels in exhaled air of rat lung allografts.

In organ transplantation nitric oxide has been reported to be involved in allograft rejection. We examined in a rat lung transplantation model whether nitric oxide is overproduced in acute rejection and can be detected in exhaled air. Thirteen rat right lung transplants were separated into three groups: group 1 (n = 5), untreated allografts (Brown-Norway [RT1n] to Lewis [RT1l]); group 2 (n = 4), cyclosporine-treated allografts; and group 3 (n = 4), isografts (Lewis to Lewis). We examined exhaled nitric oxide levels with a chemiluminescence analyzer and chest roentgenograms on days 2 through 5. Histologic samples were obtained on days 3 and 5. On day 5, the recipients were killed and we measured exhaled nitric oxide from the right and left lungs separately. Blood samples were also obtained for measurement of serum nitrite/nitrate. The exhaled nitric oxide level in untreated allografts increased significantly from day 5 (63.9 +/- 39.2 ppb, p = 0.0095) and was significantly higher than that in treated allografts (9.1 +/- 1.6 ppb) (p = 0.0085) and isografts (6.9 +/- 0.5 ppb) (p = 0.0068). The nitric oxide level in untreated allografts (826.5 +/- 416.1 ppb) was 75 times as high as that from the contralateral normal left lungs (11.2 +/- 2.6 ppb) (p = 0.0118). The level of exhaled nitric oxide correlated significantly with the histologic rejection grade (p = 0.0001). There was no significant difference in the serum nitrite/nitrate levels between allografts and isografts. These data suggest that increased exhaled nitric oxide levels might reflect acute rejection in lung transplants.

RD6-2198, a novel betain-type fluoroalkylated oligomer, inhibits the replications of human immunodeficiency virus type 1 and other enveloped viruses.

We have examined a novel betain-type fluoroalkylated oligomer, RD6-2198, for its inhibitory effects on the replication of human immunodeficiency virus type 1 (HIV-1) and other enveloped viruses, including herpes simplex virus types 1 and 2 (HSV-1 and HSV-2, respectively) and respiratory syncytial virus (RSV) in cell cultures. We have found that the compound is a potent and selective inhibitor of these viruses. RD6-2198 inhibited the replication of HIV-1IIIB at a concentration of 0.85 microg/ml with a selectivity index greater than 59 in MT-4 cells. Furthermore, its 50% effective concentration (EC50) values for HSV-1, HSV-2 and RSV, were 0.51, 0.94 and 3.0 microg/ml, respectively. We found that the RD6-2198 suppressed the gp120-CD4 interaction (as monitored by an enzyme-linked immunosorbent assay (ELISA) method). RD6-2198 also inhibited the binding of anti-gp120 monoclonal antibody to gp120 expressed on MOLT-4/IIIB cells (MOLT-4 cells chronically infected with HIV-1IIIB). However, the compound did not inhibit the interaction of anti-CD4 antibody with CD4. These results suggest that RD6-2198 interacts with the viral envelope glycoprotein and thereby inhibits the viral adsorption process. In addition, RD6-2198 was also found to suppress the proliferation of MOLT-4/IIIB cells. When applied topically, RD6-2198 at a concentration of 10 mg/ml completely protected mice from an intravaginal HSV-2 infection.

Exercise performance of rats after isogenic left or right lung transplantation followed by contralateral pulmonary artery ligation.

BACKGROUND: After single lung transplantation for pulmonary hypertension, large mismatches in ventilation/perfusion distribution persist late after transplantation. The larger graft volume of the transplanted lung after transplantation, the better the exercise performance. Because the right lung is larger in volume than the left, we compared the left single lung transplant with the right single lung transplant regarding exercise performance with an animal model. METHODS: To simulate significant ventilation/perfusion imbalance observed after single lung transplantation for pulmonary hypertension, we transplanted isogenic left or right pulmonary grafts to normal rats, and the contralateral pulmonary artery was ligated 2 weeks after transplantation. The treadmill test was performed weekly until 6 weeks after transplantation to measure maximum tolerated running speed and maximum oxygen uptake. RESULTS: Graft vital capacity of left and right pulmonary grafts were 4.5 +/- 0.43 ml (37% +/- 3.7% of recipient's predicted vital capacity) and 7.8 +/- 0.34 ml (63% +/- 2.4%), respectively (p < 0.01). Maximum tolerated speeds of left and right single lung transplants were 8 +/- 7.6 and 29 +/- 2.2 m/min, respectively, at 6 weeks after transplantation (p < 0.01). Maximal oxygen uptake values of left and right single lung transplants were 34 +/- 12.0 and 65 +/- 3.8 ml/kg/min, respectively (p < 0.01). CONCLUSIONS: Results suggest that right lung transplantation is superior to left lung transplantation for pulmonary hypertension in terms of exercise performance in this animal model.

Monocrotaline-induced pulmonary vascular disease after contralateral lung transplantation in the rat.

To test a hypothesis that reduction in pulmonary perfusion pressure and flow affect underlying vascular disease, pulmonary pathology was studied in monocrotaline-treated rats undergoing single lung transplantation. Inbred rats were treated with 40 mg/kg (group T1, n = 6) and 80 mg/kg of monocrotaline (group T2, n = 9), received a left lung isograft 2 and 4 weeks after medication, and were killed 4 and 6 weeks after single lung transplantation, respectively. For each group, rats receiving the same amount of monocrotaline (M1, M2) or vehicle (N1, N2) served as controls. Monocrotaline-treated rats developed pulmonary vascular disease and right heart failure, resulting in severe exercise intolerance in M1 or death in M2 unless single lung transplantation had been carried out. At death, pulmonary blood flow was directed toward the left lung isograft, and the retained right lung received a significantly reduced fraction of cardiac output. Right to left ventricular weight ratio was significantly reduced in both groups as compared to the respective control rats, suggesting reduced perfusion pressure. Although thickness of media in small pulmonary arteries (media/radius) was normal (34% +/- 4%) in the lung isografts, it was significantly increased in the contralateral lung (group T1, 45% +/- 5%; group T2, 48% +/- 3%), which was not significantly different from that of monocrotaline-treated control rats, respectively (group M1, 47% +/- 7%; group M2, 49% +/- 6%). Although single lung transplantation reduced perfusion pressure and flow toward the monocrotaline-treated native lung, it failed to affect vascular morphology significantly.

Histamine release from pulmonary mast cells after lung transplantation in rats.

BACKGROUND AND METHODS: On the assumption that lung mast cells might respond and release histamine after lung transplantation, the number of mast cells and tissue histamine content were investigated for 2 weeks after rat orthotopic left lung isotransplantation (Lewis rat to Lewis rat) and allotransplantation (Lewis rat to Brown Norway rat). The allografts were rejected histologically by day 7 (grade A4). RESULTS: In the isografts, both the numbers of mast cells and histamine content were lower (p < 0.05) on day 4 but higher (p < 0.001) on day 14 compared with the nontransplanted donor left lungs (control). In the allografts, the numbers of mast cells on day 7 and histamine content on day 1 were lower (p < 0.05) than controls and both continued to be low thereafter. On day 7, the histamine content of the allografts was low (p < 0.05) compared with the level of the isografts. Conversely, no significant change was found in histamine content of the untransplanted right native lungs except for on day 14 after isotransplantation, when the content was higher than the controls, suggesting the possibility of a systemic signal for proliferation of mast cells. CONCLUSIONS: Our data indicated that degranulation of the pulmonary mast cells and consequent histamine release localized in the grafts occurred under the microenvironment of reimplantation and rejection after rat lung transplantation.

Human laminin M chain: epitope analysis of its monoclonal antibodies by immunoscreening of cDNA clones and tissue expression.

We have produced four monoclonal antibodies (mAbs) against human placenta laminin purified by immunoaffinity chromatography. Three clones, 2D9, 3DM, and 4F1, recognized 320 kDa (M) chain of the laminin and the other one, 3DB, recognized B2 chain. One cDNA clone (HLM-1, 3.5 kb) was immunoscreened from human placenta cDNA library using 2D9, and three further overlapping cDNA clones (HLM-2, HLM-3, and HLM-4) covering 2.0 kb were isolated. Nucleotide sequencing and fusion protein analysis demonstrated that the amino acid sequence deduced from HLM-1 coincided with that of the G-domain of human merosin chain, and HLM-2, HLM-3, and HLM-4 encoded the long-arm and EGF-like domain of M chain. The binding regions of 2D9 and 3DM to M chain were defined as homologous repeating sequences of G2-G3 region of G-domain and the carboxy-terminal region of the long-arm, respectively. The extents of identity of amino acid sequences of the long-arm and EGF-like domains between human M chain and A chain were about 37% and 52%, respectively, which were lower than between mouse and human A chains. Northern blot analysis revealed that M chain mRNA, 8.6 kb, was highly expressed in heart and placenta, but less highly expressed in skeletal muscle, brain, and lung. Immunostaining showed selective distributions of M chain in nerve fibers in the dermis and mesangial matrix of the kidney, and B2 chain in subepidermal and kidney glomerular basement membranes.

Serum lipoprotein(a) levels before and after subtotal thyroidectomy in subjects with hyperthyroidism.

Lipoprotein(a) [Lp(a)], a lipoprotein that structurally resembles low-density lipoprotein (LDL), contains apolipoprotein(a) [apo(a)] and apolipoprotein B-100 (apo B). There exists a close inverse correlation between serum concentrations of LDL or apo B and concentrations of thyroid hormone in patients with thyroid disease, probably due to a change in LDL receptor activity. To clarify the relations between thyroid hormone and Lp(a), we measured serum Lp(a) levels in 13 hyperthyroid subjects before treatment (stage H), during the euthyroid stage induced immediately before performing a subtotal thyroidectomy (stage E), and during the hypothyroid stage observed transiently after the operation (stage L). The mean serum concentration of Lp(a) increased significantly (P = .01) from 9.4 mg/dL in stage H to 26.8 in stage L through the level of 15.5 mg/dL in stage E. There was no significant difference between the mean serum concentration of Lp(a) in these patients in stage E and healthy controls (14.2 mg/dL). There was a low but statistically significant negative correlation between the Lp(a) level and the serum free thyroxine (fT4) concentration (r = .31, P < .05). The results suggest that thyroid hormone is a potent modulator of Lp(a) metabolism.