Effect of dasatinib in a xenograft mouse model of canine histiocytic sarcoma and in vitro expression status of its potential target EPHA2

Canine histiocytic sarcoma (HS) is an aggressive and highly metastatic tumor. Previously, the kinase inhibitor dasatinib was shown to have potent growth inhibitory activity against HS cells in vitro, possibly via targeting the EPHA2 receptor. Here, the in vivo effect of dasatinib in HS cells was investigated using a xenograft mouse model. Moreover, the expression status of EPHA2 was examined in six HS cell lines, ranging from insensitive to highly sensitive to dasatinib. In the HS xenograft mouse model, dasatinib significantly suppressed tumor growth, as illustrated by a decrease in mitotic and Ki67 indices and an increase in apoptotic index in tumor tissues. On Western blot analysis, EPHA2 was only weakly detected in all HS cell lines, regardless of sensitivity to dasatinib. Dasatinib likely results in the inhibition of xenograft tumor growth via a mechanism other than targeting EPHA2. The findings of this study suggest that dasatinib is a targeted therapy drug worthy of further exploration for the treatment of canine HS.

Selective growth inhibition by suppression of F1Fo ATPase in canine malignant melanoma cell lines

Canine malignant melanoma (CMM) is a highly aggressive and fatal neoplasm. To identify potential therapeutic compounds and/or targets, 320 compounds were screened for their growth inhibitory activity in a CMM line (CMM-1) using a chemical library known to target specific signaling pathways/cell growth-related molecules. Among the compounds screened, the F1Fo ATPase inhibitor oligomycin showed potent growth inhibitory effects in CMM-1 cells, while exhibiting less toxic effects in a non-neoplastic control cell line (MDCK cells). The growth inhibitory effect of oligomycin A was then examined using six CMM lines and MDCK cells. Three CMM lines were highly sensitive to oligomycin A, with around 3000-20 000 times lower IC₅₀ compared with oligomycin A-resistant CMM lines and MDCK cells. Oligomycin A-sensitive CMM-1 cells exhibited much greater oligomycin A-induced decreases in cellular ATP compared to oligomycin A-resistant cell lines. Although the oligomycins are clinically unsuitable because of its in vivo toxicity, these findings implicate the potential of F1Fo ATPase as a therapeutic target in a subset of CMM.

Anticancer effects of gemcitabine are enhanced by co-administered iRGD peptide in murine pancreatic cancer models that overexpressed neuropilin-1

BACKGROUND

Impaired drug transport is an important factor that reduces the efficacy of anticancer agents against pancreatic cancer. Here, we report a novel combination chemotherapy using gemcitabine (GEM) and internalised-RGD (iRGD) peptide, which enhances tumour-specific drug penetration by binding neuropilin-1 (NRP1) receptor.

METHODS

A total of five pancreatic cancer murine models (two cell line-based xenografts (CXs) and three tumour grafts (TGs)) were treated with either GEM (100 mg kg(-1), q3d × 4) alone or GEM plus iRGD peptide (8 μmol kg(-1)). Evaluation of NRP1 expression in xenografts and 48 clinical cancer specimens was performed by immunohistochemistry (IHC).

RESULTS

We identified a subset of pancreatic cancer models that showed NRP1 overexpression sensitive to iRGD co-administration. Treatment with GEM plus iRGD peptide resulted in a significant tumour reduction compared with GEM monotherapy in CXs, but not remarkable in TGs. Potential targets of iRGD were characterised as cases showing NRP1 overexpression (IHC-2+/3+), and these accounted for 45.8% of the clinical specimens.

CONCLUSIONS

Internalised RGD peptide enhances the effects of co-administered drugs in pancreatic cancer models, its efficacy is however only appreciable in those employing cell lines. Therefore, the clinical application needs to be given careful consideration.

Abstract OT1-1-01: A phase II study of neoadjuvant epirubicin/cyclophosphamide (EC) followed by weekly nanoparticle albumin-bound paclitaxel with or without trastuzumab for node-positive breast cancer

Background: Paclitaxel is considered standard treatment for metastatic breast cancer (MBC) and is often used as adjuvant and neoadjuvant chemotherapy for patients with early-stage disease. Conventional paclitaxel requires solvents such as polyoxyethylated castor oil; however, such solvents are associated with toxicity including peripheral neuropathy and hypersensitivity reaction. Moreover, the use of the drug requires special tubing and in-line filters. Therefore, nanoparticle albumin-bound paclitaxel (nab-PTX) requiring no solvent has been developed. Nab-PTX was effective in patients with MBC and as a neoadjuvant therapy. A comparison between weekly and triweekly nab-PTX suggested that weekly nab-PTX was superior in progression-free survival.

Trial design: This is a phase II trial to evaluate the efficacy and toxicity of neoadjuvant epirubicin/cyclophosphamide (EC) (epirubicin/cyclophosphamide) followed by weekly nab-PTX with or without trastuzumab for node-positive breast cancer. Patients receive four cycles of epirubicin (90 mg/m2) and cyclophosphamide (600 mg/m2) every 3 weeks, followed by four cycles of nab-PTX (125 mg/m2) on days 1, 8 and 15 in a 28-day cycle. Fifteen cycles of trastuzumab (2 mg/kg, loading 4 mg/kg) are added to the nab-PTX regimen in HER2-positive patients every week.

Eligibility criteria: Patients with histologically diagnosed invasive breast cancer based on a core needle biopsy of the T1-4 N1-3 without previous operation or chemotherapy are included in this trial. Eligible patients are aged between 20 years and 70 years with a performance status of 0 to 2 and adequate organ functions.

Specific aims: The primary endpoint is the pathologic complete response (pCR) rate in the breast and axilla, and the secondary endpoints are the breast conserving rate, toxicities, feasibility and overall survival.

Statistical methods: The sample size was calculated using the Simon method, with a type I error of 10% and a study power of 80%. 1. HER2-negative patients

The expected rate of pCR was 25% and the required number of patients was estimated to be 33. 2. HER2-positive patients

The expected rate of pCR was 50%, and the required number of patients was estimated to be 21.

Present and target accrual: Patient accrual within two medical centers started in April 2011 with 20 patients being on study to date (2012, June 12). A total of 56 patients (22 are HER2-positive and 34 are HER2-negative) are planned to be enrolled in the trial.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT1-1-01.

Decrease of blood dendritic cells and increase of tissue-infiltrating dendritic cells are involved in the induction of Sjögren's syndrome but not in the maintenance

We have demonstrated previously that, in primary Sjögren's syndrome (SS), immature myeloid dendritic cells (DCs) are decreased in blood and mature myeloid DCs are accumulated in salivary glands, suggesting recruitment of the myeloid DCs from blood to salivary glands. To verify whether this finding is universal in patients of not only primary SS but also secondary SS, in this study we analysed the blood DCs of secondary SS patients. We examined 24 secondary SS and 29 primary SS patients. A direct correlation between the decreased number of myeloid DCs and the duration of Sicca syndrome in primary and secondary SS was observed; namely, the reduction of myeloid DCs in blood was restored spontaneously with duration time of Sicca syndrome. We also examined the immunohistochemical staining of salivary glands of SS patients with monoclonal antibodies against fascin, CD11c and human leucocyte antigen DR (HLA-DR). Fascin(+) or CD11c(+)/HLA-DR(+) mononuclear cells were present in the salivary glands of secondary SS patients, as in primary SS. However, fascin(+) mononuclear cells were barely detected in the salivary glands of a chronic phase of SS patients. We also found a negative correlation between the frequency of blood myeloid DCs and salivary gland-infiltrating DCs in secondary SS patients, as well as primary SS. Our results suggest that the reduction of blood myeloid DCs and preferential trafficking of myeloid DCs into salivary glands is a common event in the early stage of SS. Myeloid DCs may play essential roles in the pathogenesis of Sicca syndrome of SS by initiating T helper cell immune responses.

Purification and comparison of triosephosphate isomerases from ammonia-oxidizing bacteria isolated from terrestrial and marine environments

Triosephosphate isomerases [TIMs, EC 5.3.1.1] were purified from two ammonia-oxidizing bacteria: Nitrosomonas sp. K1 (K1), Nitrosomonas sp. TNO632 (TNO). The molecular masses of the native enzymes were estimated to be about 53.6 (K1-TIM) and 51.9 kDa (TNO-TIM) by gel filtration, whereas SDS-PAGE produced one band for each enzyme with M(r) values of 27.1 (K1-TIM) and 26.4 kDa (TNO-TIM), respectively, suggesting that the enzymes consist of identical subunits. The apparent K(m) for d-glyceraldehyde-3-phosphate (GAP) and dihydroxyacetone phosphate (DHAP) were about 1.19 and 4.78 mM (K1-TIM), and 0.41 and 6.01 mM (TNO-TIM), respectively. The two TIMs had different pH-activity curves with an optimum pH range of 6.5 (K1-TIM) and 8.0 (TNO-TIM). The temperature optima of K1-TIM and TNO-TIM were 50-60 and 60-65 degrees C, respectively. Both enzymes were strongly inhibited by 5,5'-ditiobis at 1.0 mM. The N-terminal amino acid sequences of K1-TIM and TNO-TIM were MRAGFVAGNWKMHG (K1-TIM) and MVRTGLVAGNWKMNG (TNO-TIM). A homology of 74.1% was observed between K1-TIM and TNO-TIM.

[A clinical investigation of oro-maxillary sinus-perforation due to tooth extraction]

Oro-maxillary sinus perforation occurs occasionally at the extraction of a maxillary tooth, and it may be a cause of maxillary sinusitis or antro-oral fistula. Our purpose was to investigate the most frequent site of perforation, and to understand the clinical course of patients after perforation. We examined 2,038 maxillary teeth extracted from 1,337 patients (473 males and 864 females) at the First Department of Oral and Maxillofacial Surgery, Tokyo Medical and Dental University, from January 1991 to December 1993. Perforation occurred in 77 of all 2,038 teeth (3.8%). Of these, 38 teeth were from males (38/733; 5.2%), and 39 were from females (39/1,305; 3.0%). The perforation rate was significantly higher in males. Perforation occurred most often with extraction of an upper first molar, and in the third decade of life. The perforation rate gradually decreased with higher age. We classified 38 cases into 3 categories according to panorama X-P: 1) The tip of the root crossed over the bottom line of the maxillary sinus (29 cases), 2) Not crossed over distinctly (4 cases), 3) Just lie on, or whether the tip of the root crossed over the bottom line of the maxillary sinus was not distinct (5 cases). As to treatment, 30 perforations (39.0%) closed spontaneously in the course of observation, irrigation with physiological saline was used in 43 cases (55.8%), radical sinusotomy accompanied by closure of the perforation was performed in 4 cases, and only flap closure was used in 7 cases. There were no cases of relapse.

Cumulative effect of family environment on psychiatric symptomatology among multiethnic adolescents

PURPOSE

To examine the influence of family adversity and support on levels of psychiatric symptomatology in Hawaiian and non-Hawaiian adolescents.

METHOD

More than 4000 students from five high schools in Hawaii completed a survey during the 1992-1993 school year about their family environment and mental health. The response rate was approximately 60%. Logistic regression analyses were performed and responses for Hawaiians and non-Hawaiians were compared.

RESULTS

Hawaiian adolescents experienced significantly more adversity than their non-Hawaiian counterparts. The cumulative effect of family adversity had a greater effect on psychiatric symptomatology than any single indicator. Family support reduced the risk for internalizing symptoms, particularly for Hawaiian adolescents. The influence of family support was less clear for externalizing symptoms, increasing the risk for some adolescents and decreasing the risk for others.

CONCLUSION

We identified strong associations between family adversity and levels of psychiatric symptomatology. We found that Hawaiian adolescents are at increased risk for psychiatric symptomatology, given the presence of family adversity and the effect of reduced family support. However, risk was also substantial for non-Hawaiians. Clinicians need to assess the family environment routinely and implement family-oriented interventions.

Tol1, a fission yeast phosphomonoesterase, is an in vivo target of lithium, and its deletion leads to sulfite auxotrophy

Lithium is the drug of choice for the treatment of bipolar affective disorder. The identification of an in vivo target of lithium in fission yeast as a model organism may help in the understanding of lithium therapy. For this purpose, we have isolated genes whose overexpression improved cell growth under high LiCl concentrations. Overexpression of tol1(+), one of the isolated genes, increased the tolerance of wild-type yeast cells for LiCl but not for NaCl. tol1(+) encodes a member of the lithium-sensitive phosphomonoesterase protein family, and it exerts dual enzymatic activities, 3'(2'),5'-bisphosphate nucleotidase and inositol polyphosphate 1-phosphatase. tol1(+) gene-disrupted cells required high concentrations of sulfite in the medium for growth. Consistently, sulfite repressed the sulfate assimilation pathway in fission yeast. However, tol1(+) gene-disrupted cells could not fully recover from their growth defect and abnormal morphology even when the medium was supplemented with sulfite, suggesting the possible implication of inositol polyphosphate 1-phosphatase activity for cell growth and morphology. Given the remarkable functional conservation of the lithium-sensitive dual-specificity phosphomonoesterase between fission yeast and higher-eukaryotic cells during evolution, it may represent a likely in vivo target of lithium action across many species.

Audition and visual attention: the developmental trajectory in deaf and hearing populations

This study examined the development of visual attention in 5- to 13-year-olds who differed in their access to sound. Hearing children, deaf children with cochlear implants, and deaf children without implants participated in a task in which they were to respond to some visual signals and not others. The results of Experiment I indicated that the timing of developmental changes in visual selective attention was similar for all 3 groups, occurring around 8 years. The magnitude of age-related change differed among groups; hearing children and older deaf children using a cochlear implant reached higher levels of performance with age than did deaf children without enhanced access to sound. The results of Experiment 2 suggest that the developmental differences between deaf children with and without cochlear implants begin prior to 8 years and may be related to their use of environmental sounds to organize visual attention.

Tolerance of NK and LAK activity for HLA class I-deficient targets in a TAP1-deficient patient (bare lymphocyte syndrome type I)

NK cells recognize target cells that lack HLA class I molecules and lyse them, according to the 'missing self' hypothesis. It was previously reported that a TAP2-deficient patient with an HLA class I-deficiency, had a normal number of NK cells but that the lymphocytes of this patient had lost their NK activity against K562 cells. In this study, we investigated the HLA class I-recognizing NK receptor expressions and the NK and LAK activities of the lymphocytes of a TAP1-deficient patient. The patient had a normal number of NK cells. Although the lymphocytes showed LAK activity against class I expressing targets following IL-2, IL-12 and IL-15 stimulation for 3 days, neither NK nor LAK activity against targets lacking class I molecules was induced. The NK cells of the patient expressed class I-recognizing NK receptors, although the percentages of such cells were low. However, no differences were observed in the expression levels of inhibitory and activating NK receptors between lymphocytes of the patient and those of healthy controls, suggesting that the modulation of the NK receptor expression is not primarily responsible for this tolerance. These results also suggest that the lymphocytes of the patient are defective in the recognition of class I-deficient target cells in order to promote the induction of self tolerance.

Audition and visual attention: the developmental trajectory in deaf and hearing populations

This study examined the development of visual attention in 5- to 13-year-olds who differed in their access to sound. Hearing children, deaf children with cochlear implants, and deaf children without implants participated in a task in which they were to respond to some visual signals and not others. The results of Experiment I indicated that the timing of developmental changes in visual selective attention was similar for all 3 groups, occurring around 8 years. The magnitude of age-related change differed among groups; hearing children and older deaf children using a cochlear implant reached higher levels of performance with age than did deaf children without enhanced access to sound. The results of Experiment 2 suggest that the developmental differences between deaf children with and without cochlear implants begin prior to 8 years and may be related to their use of environmental sounds to organize visual attention.

Subcellular distribution of 220 kDa antigen in the intercellular spaces of normal human epidermis

We generated a monoclonal antibody, 7C1, to an extract of pig snout skin used as antigen. The antigen for 7C1 was identified by immunoblotting as a 220 kDa epidermal protein. It was found immunologically to be distributed mainly in the intercellular spaces throughout the living cell layers of normal human epidermis, but its distribution changed in some keratinizing disorders. Study of the association of this protein with subcellular structures by immunoelectron microscopy of normal human skin revealed that it was localized in (1) lamellar granules, (2) intercellular spaces, especially in the lamellar structures derived from the lamellar granules, (3) small vesicles near the cell boundaries and (4) small vesicles in the Golgi apparatus. These results suggest that in humans the 220 kDa protein originates in the Golgi apparatus and is secreted via either the lamellar granules or the small secretory vesicles into the intercellular spaces of the epidermis, where it may be involved in the epidermal permeability barrier function and possibly in keratinizing differentiation.

Carotid body tumors, inheritance, and a high incidence of associated cervical paragangliomas

BACKGROUND

Current experience with carotid body tumors suggesting a high prevalence of associated cervical paragangliomas prompted this review.

PATIENTS AND METHODS

An 8-year retrospective study of patients with carotid body tumors was undertaken, detailing presentation, diagnosis, and treatment.

RESULTS

Eleven patients harboring 17 carotid body tumors were discovered. All patients had a neck mass. Seven patients (64%) had bilateral carotid body tumors. Six (55%) reported a positive family history-4 were first-generation relatives, 5 had bilateral tumors, and 3 had other head and neck paragangliomas. Angiography documented 4 associated vagal and 2 glomus jugulare paragangliomas in addition to the carotid body tumors. Precise surgical care limited blood loss to an average of 590 cc. The carotid artery was repaired during 5 resections (29%). Cranial nerve injury occurred in 3 cases, all following vagal body or glomus jugulare resection. Every patient is currently alive, stroke free, and functioning without major disability.

CONCLUSIONS

Patients with carotid body tumors have a propensity for multiple head and neck paragangliomas. Angiography is diagnostic. The need for associated paraganglioma resection dramatically increases the risk of cranial nerve injury.

Differential regulation of the expression in transgenic tobacco of the gene for beta-glucuronidase under the control of the 5'-upstream regions of two catalase genes from castor bean

The regulatory functions of the 5'-flanking regions of two genes for catalase (cat1 and cat2) from castor bean were analyzed in transgenic tobacco plants that carried fusion constructs that included the gene for beta-glucuronidase (GUS) for Escherichia coli. Dry mature seeds from transgenic plants carrying the CAT1-GUS or CAT2-GUS constructs, in which the GUS gene was fused to the 5'-flanking region of cat1 or cat2, respectively, contained significant GUS activity, indicating that the promoters of cat1 and cat2 were active during seed development. GUS activity increased in response to germination in the seeds of transgenic tobacco that carried CAT1-GUS, as well as in those that carried CAT2-GUS. During the post-germinative stage the GUS activity directed by CAT2-GUS increased still further, whereas that directed by CAT1-GUS decreased. The changes in GUS activity in the transgenic tobacco plants that carried CAT1-GUS and CAT2-GUS were similar to the changes in the levels of transcripts of cat1 and cat2, respectively, in castor bean. The results suggest that the expression of cat1 and cat2 in the germinating seeds and post-germinative seedlings is regulated mainly at the level of transcription. However, the distribution of GUS activity among the organs of the transgenic tobacco seedlings and plantlets, which was examined by histochemical staining and by enzymatic assays of tissue extracts, was not identical to that of transcripts of cat1 and cat2 in castor bean. Histochemical analysis also revealed the interesting spatial regulation of the expression of the promoter of cat2 in the transgenic tobacco seedlings.

Intrafamilial clustering of genotypes of hepatitis C virus RNA

Hepatitis C virus (HCV)-RNA in the blood was measured by polymerase chain reaction (PCR) in 37 subjects from eight families in which 2 or more persons tested seropositive for antibodies against C100-3 or CP9. HCV-RNA was positive in 17 of 37 subjects. Two or more HCV-RNA-positive subjects were observed in six of the families. Intrafamilial HCV infection was studied by determining the HCV-RNA type (I, II, III or IV) by PCR using type-specific primers. In two families, all of the subjects showed type III infection, and in three other families, all of the subjects showed type II infection, with different types of HCV infections being observed in only one family. The HCV type was uniform in all but one. These findings suggest a possibility of intrafamilial infection between husbands and wives and between members of the same household.

Three subtypes of poroid neoplasia in a single lesion: eccrine poroma, hidroacanthoma simplex, and dermal duct tumor. Histologic, histochemical, and ultrastructural findings

A single poroid neoplasm composed of three histologically distinct lesions (hidroacanthomas simplex, eccrine poroma, and dermal duct tumor) is reported. Comparative histologic, histochemical, and electron-microscopic studies revealed that each tumor subtype contained varying proportions of poroid cells, clear cells, and cuticular cells. The major component of all three neoplasms was poroid cells, which, under the electron microscope, were characterized by a few, small, poorly developed desmosomes, and were histochemically characterized by a positive succinic dehydrogenase reaction. The dermal duct tumor was cultured, and showed similar histochemical findings to the in vivo poroid cells. These results suggest that poroid cells play the most important role in the histogenesis of these three neoplasms.

Concomitant occurrence of circulating IgA anti-intercellular and anti-basement membrane zone antibodies in autoimmune blistering diseases: immunofluorescence and immunoblot studies

Recently, cases with circulating IgA anti-intercellular antibodies have been described. The objective of this study was to present immunofluorescence and immunoblot findings in three cases of bullous diseases with concomitant circulating IgA anti-intercellular and anti-basement membrane zone antibodies. Direct immunofluorescence, indirect immunofluorescence on intact and 1M NaCl-split skin, immunoblotting of epidermal extracts from dispase- and EDTA-separated (two different procedures) human skin, and immunoblotting of the bovine desmosome preparation were performed. All three cases had IgA anti-intercellular and anti-basement membrane zone antibodies. However, immunoblot results were divergent. Case 1 had antibodies against the 150 kD pemphigus foliaceus antigen (IgG), the 170 kD protein (IgG and IgA), and the 97 kD antigen (IgG and IgA). Case 2 had IgG antibodies reactive with the 230 kD and the 170 kD bullous pemphigoid antigens, while case 3 had IgA antibodies against the 97 kD antigen only. The results of immunofluorescence and immunoblot studies in our patients widen the spectrum of laboratory features in blistering skin diseases mediated, at least in part, by antibodies of the IgA class.

Natural course of chronic hepatitis C

We studied 333 chronic hepatitis C patients to evaluate the natural course of this disease. Among 57 patients undergoing serial biopsies, 20 had chronic persistent hepatitis (CPH) at the first biopsy, and 10 of them progressed to chronic active hepatitis (CAH) or liver cirrhosis (LC) after 11 yr. Sixteen patients had CAH 2A, and this progressed to CAH 2B or LC in 10 cases over 9 yr. Among the 21 patients with CAH 2B, progression to LC was noted in 15 after 7 yr. Among the 100 patients observed for over 5 yr, the normalization of liver function for at least 3 yr was seen in only four patients. In two of these four patients, serum HCV-RNA was tested serially. Despite the sustained normalization of alanine aminotransferase levels, HCV-RNA continued to be detectable in one patient. We conclude that many patients with chronic hepatitis C eventually show progression of their disease after a long and symptomless course.

Quantitative hepatitis C virus RNA and liver histology in chronic hepatitis C patients treated with interferon alfa

Seventy patients with hepatitis C virus (HCV) infection received alpha interferon at doses ranging from 3 to 10 million units (MU) daily for eight weeks, three times weekly for 12-24 weeks, or daily and three times weekly for 12-24 weeks. The efficacy of interferon was closely related to the initial blood HCV-RNA values in that these were lower in those who responded completely and partially compared with non-responders. Continuous reductions in HCV-RNA and improvements in the histology activity index score were seen in those who responded completely. In contrast, most of the partial and non-responders remained HCV-RNA positive.

Hepatitis type C virus infection in patients with type B chronic liver disease

Anti-c100-3 (Ortho) was determined in the sera of 152 patients with HBs antigen-positive chronic liver diseases to assess coinfection of hepatitis B virus (HBV) and hepatitis C virus (HCV). Eleven patients (7.2%) were positive for anti-c100-3. Anti-CP-9 (Okamoto) and HCV-RNA (RT-PCR) were also examined in these 11 patients. Anti-CP-9 was detected in 7 patients and HCV-RNA was detected in all 11 patients. Four of the 11 anti-c100-3-positive patients were positive for HBe antigen (HBeAg) and others were negative. In 8 of the 11 patients, HCV was suspected to be superinfected by blood transfusion. In HBeAg-positive patients, serum glutamic pyruvic transaminase (SGPT) was elevated in relation to active replication of HBV shown by DNA-polymerase activity. The histological findings showed chronic active hepatitis, with or without cirrhosis. On the other hand, in HBeAg-negative patients, SGPT fluctuated without evidence of active replication of HBV. Active inflammation in the liver was observed in 3 of 5 HBeAg-negative patients by liver biopsy. These findings suggest that HBV might play an important role in chronic active inflammation in HBeAg-positive patients coinfected with HCV, and that HCV might be responsible for continuous inflammation in HBeAg-negative patients coinfected with HCV.

Hepatitis C virus antibody titration in patients with chronic hepatitis C, before and after interferon treatment

We measured hepatitis C virus antibody titers in 13 patients with chronic hepatitis C to determine whether titration of hepatitis C virus antibody was useful or not, to predict and evaluate the efficacy of interferon (IFN) treatment. During administration of IFN, hepatitis C virus titers declined in all patients. Antibody titers performed before treatment as well as just at the end of treatment did not correlate with change of the alanine aminotransferase levels during administration of IFN. Antibody titers declined continuously after treatment in 5 patients with normal alanine amino-transferase levels for over 6 months after discontinuation of IFN. Antibody titers rose again in 6 patients whose alanine aminotransferase levels fluctuated after treatment. An exceptional pattern of change occurred in 2 patients whose antibody titers declined continuously although their alanine aminotransferase levels fluctuated after treatment. Repeated titration of hepatitis C virus antibody appears to be useful for evaluating the long-term efficacy of IFN treatment.