Biological response of nonhuman primates to controlled levels of acute blood loss

Introduction

The global shortage of human blood for medical use has prompted the development of alternative blood sources. Nonhuman primates (NHPs) are commonly used owing to their physiological similarities to humans. The objective of the current study was to establish a controlled-blood-loss model in NHPs to explore their clinical and biological responses.

Methods

Blood was sequentially withdrawn from 10 cynomolgus monkeys (10, 14, 18, 22, and 25% of the total blood volume); their vital signs were monitored, and blood parameters were serially analyzed. Humoral mediators in the blood were measured using flow cytometry and enzyme-linked immunosorbent assays.

Results

In NHPs subjects to 25% blood loss and presenting with related clinical symptoms, the systolic blood pressure ratio on day 0 after bleeding was significantly lower than that of the animals from the other groups (median: 0.65 vs. 0.88, P = 0.0444). Red blood cell counts from day 0-14 and hematocrit levels from day 0-7 were markedly decreased relative to the baseline (P < 0.01). These parameters showed a direct correlation with the extent of blood loss. The levels of creatine phosphokinase, aspartate aminotransferase, and alanine aminotransferase exhibited increases in response to blood loss and had a stronger correlation with the hemoglobin ratio than the volume of blood loss. The levels of C3a and C4a, as well as interleukin (IL)-1α and IL-15, displayed a strong correlation, with no apparent association with blood loss.

Conclusion

The findings of the present study showed that only NHPs with 25% blood loss exhibited clinical decompensation and significant systolic blood pressure reduction without fatalities, suggesting that this level of blood loss is suitable for evaluating blood transfusion efficacy or other treatments in NHP models. In addition, the ratio of hemoglobin may serve as a more dependable marker for predicting clinical status than the actual volume of blood loss. Thus, our study could serve as a basis for future xenotransfusion research and to predict biological responses to massive blood loss in humans where controlled experiments cannot be ethically performed.

Initial investigation on the feasibility of porcine red blood cells from genetically modified pigs as an alternative to human red blood cells for transfusion

The decline in blood donation rates and the ongoing shortage of blood products pose significant challenges to medical societies. One potential solution is to use porcine red blood cells (pRBCs) from genetically modified pigs as an alternative to human red blood cells (hRBCs). However, adverse immunological reactions remain a significant obstacle to their use. This study aimed to evaluate the compatibility of diverse genetically modified pRBCs with human serum. We acquired human complement-competent serum, complement 7 (C7)-deficient serum, and hRBCs from all ABO blood types. Additionally, we used leftover clinical samples from health checkups for further evaluation. pRBCs were collected from wild-type (WT) and genetically modified pigs: triple knockout (TKO), quadruple KO (QKO), and TKO/hCD55.hCD39 knockin (hCD55.hCD39KI). The extent of C3 deposition on RBCs was measured using flow cytometry after incubation in C7-deficient serum diluted in Ca++-enriched or Ca++-depleted and Mg++-enriched buffers. The binding of immunoglobulin (Ig) M/IgG antibody to RBCs after incubation in ABO-type human serum was evaluated using flow cytometry. Naïve human serum- or sensitized monkey serum-mediated hemolysis was also evaluated. Phagocytosis was assessed by incubating labeled RBCs with the human monocytic cell line THP-1 and measurement by flow cytometry. All three genetic modifications significantly improved the compatibility of pRBCs with human serum relative to that of WT pRBCs. The extent of IgM/IgG binding to genetically modified pRBCs was lower than that of WT pRBCs and similar to that of O-type hRBCs. Total and alternative pathway complement activation in all three genetically modified pRBCs was significantly weaker than that in WT pRBCs and did not differ from that in O-type hRBCs. The extent of serum-mediated hemolysis and phagocytosis of these genetically modified pRBCs was low and similar to that of O-type hRBCs. Sensitized monkey serum-mediated hemolysis in QKO and TKO/hCD55.hCD39KI pRBCs was higher than in O-type hRBCs but lower than in TKO pRBCs. The elimination of porcine carbohydrate antigens in genetically modified pigs significantly enhanced pRBC compatibility with naïve human sera, which was comparable to that of O-type hRBCs. These findings provide valuable insights into the development of pRBCs as potential alternatives to hRBCs.

Recent trends in perioperative blood transfusion during elective kidney transplantation

Background

Accurately predicting the demand for blood transfusions is crucial for blood banks. Given the potential for emergency situations, it is imperative that blood banks maintain a sufficient inventory of blood products. In this study, we examined the use of perioperative transfusions in patients undergoing elective kidney transplants.

Methods

Data on all complement-dependent cytotoxicity-crossmatched assays between 2013 and 2022 were collected. We excluded repeated assays and patients who did not undergo kidney transplantation. Transfusion records and transfusion adverse reactions were reviewed retrospectively.

Results

In total, 30 patients underwent elective kidney transplantation from 2013 to 2022. The mean age of the patients was 48.1±9.7 years. The male-to-female ratio was 1.5:1. Four patients received transfusions intraoperatively, whereas eight patients were transfused postoperatively. The postoperative hemoglobin level of the transfusion group (n=9, 8.9±1.3) was significantly lower than that of the nontransfusion group (n=21, 10.4±1.2). The most commonly transfused blood product intraoperatively was leuko-reduced filtered red blood cells, followed by fresh frozen plasma. When the study period was divided into two halves based on the time of operation, the first half showed a higher number of significant transfusions.

Conclusions

In most elective kidney transplant cases, surgery was conducted without the need for blood transfusion. The timing of transfusion, when necessary, shifted from during the operation to after the operation. The implementation of patient blood management, coupled with advancements in surgical techniques, appears to have impacted the pattern of perioperative transfusion.

The First Case of Adult Granular Acute Lymphoblastic Leukemia with DNMT3A Mutation and Monosomy 7

Granular acute lymphoblastic leukemia (ALL) is defined by the presence of intracytoplasmic granules in lymphoblastic blasts, mimicking acute myeloblastic leukemia. The disease is extremely rare in adults, and hence, the characteristics thereof are poorly understood. We report a case of a 70-year-old man diagnosed with granular ALL. Bone marrow examination showed blasts with azurophilic granules in the cytoplasm, but immunophenotyping showed B-ALL with aberrant expression of myeloid antigens CD13 and CD33. Karyotyping revealed monosomy 7, and targeted NGS showed DNMT3A mutation, which suggested poor prognosis. Despite conventional chemotherapy treatment, the patient did not achieve complete remission. He declined further chemotherapy treatment and was maintained on only supportive care. This is the first report of adult granular ALL with DNMT3A mutation and monosomy 7.

Performance Evaluation of the Aptima Assays in Comparison with the cobas 6800 Assays for the Detection of HIV-1, HBV, and HCV in Clinical Samples

Background

Accurate and consistent viral load (VL) quantitation of HIV type 1 (HIV-1), hepatitis B virus (HBV), and hepatitis C virus (HCV) is important for diagnosis and clinical monitoring. Assay results have to be concordant and compatible across laboratories. We evaluated the performance of three Aptima assays (Hologic, San Diego, CA, USA) and compared their VL values with corresponding cobas 6800 assay (Roche Diagnostics, Mannheim, Germany) results, using 840 clinical samples.

Methods

The correlation between VL results obtained using the two assays was evaluated in terms of analytical sensitivity, precision/reproducibility, linearity, and cross-reactivity. Agreement rates were determined using kappa statistics. The overall agreement of VL values was examined using Passing–Bablok regression analysis.

Results

All CVs were within 5%; the assays had good precision for detecting all three viruses. The linearity of quantitation assessed using three AccuSpan linearity panels (Seracare, Milford, MA, USA), was excellent for the Aptima assays. For HIV-1 and HCV, the results of both assays showed excellent agreement (κ=0.89 and 0.90, respectively) while for HBV, the results showed good agreement (κ=0.69). For analytical sensitivity, the VLs required for a 100% detection rate of HIV-1, HBV, and HCV were 20 copies/mL, 7.5 IU/mL, and 5.0 IU/mL, respectively. The results for HIV-1, HBV, and HCV obtained using both assays correlated strongly (R²=0.97, 0.93, and 0.95, respectively).

Conclusions

The cobas 6800 and Aptima assays, with fully automated and high-throughput molecular platforms for HIV-1, HBV, and HCV VL measurements, show good analytical performance and a strong correlation between results. The study results suggest that the assays can be used interchangeably for long-term monitoring of chronic infections.

Erythroid Differentiation of Induced Pluripotent Stem Cells Co-cultured with OP9 Cells for Diagnostic Purposes

Background

Reagent red blood cells (RBCs) are prepared from donated whole blood, resulting in various combinations of blood group antigens. This inconsistency can be resolved by producing RBCs with uniform antigen expression. Induced pluripotent stem cells (iPSCs) generated directly from mature cells constitute an unlimited source for RBC production. We aimed to produce erythroid cells from iPSCs for diagnostic purposes. We hypothesized that cultured erythroid cells express surface antigens that can be recognized by blood group antibodies.

Methods

iPSCs were co-cultured with OP9 stromal cells to stimulate differentiation into the erythroid lineage. Cell differentiation was examined using microscopy and flow cytometry. Hemoglobin electrophoresis and oxygen-binding capacity testing were performed to verify that the cultured erythroid cells functioned normally. The agglutination reactions of the cultured erythroid cells to antibodies were investigated to confirm that the cells expressed blood group antigens.

Results

The generated iPSCs showed stemness characteristics and could differentiate into the erythroid lineage. As differentiation progressed, the proportion of nucleated RBCs increased. Hemoglobin electrophoresis revealed a sharp peak in the hemoglobin F region. The oxygen-binding capacity test results were similar between normal RBCs and cultured nucleated RBCs. ABO and Rh-Hr blood grouping confirmed similar antigen expression between the donor RBCs and cultured nucleated RBCs.

Conclusions

We generated blood group antigen-expressing nucleated RBCs from iPSCs co-cultured with OP9 cells that can be used for diagnostic purposes. iPSCs from rare blood group donors could serve as an unlimited source for reagent production.

Comparison of IL-6 measurement methods with a special emphasis on COVID-19 patients according to equipment and sample type

Background

Interleukin‐6 (IL‐6) is a multifunctional cytokine associated with various diseases, including coronavirus disease (COVID‐19). Although IL‐6 levels can be assessed using serum samples, use of the AFIAS (Boditech Med Inc.) automated immunoassay analyzer enables quick and simple measurement of IL‐6 levels in both serum and whole blood specimens. This study aimed to assess the correlation between IL‐6 measurements obtained from the AFIAS IL‐6 assay and Elecsys IL‐6 assay (Roche Diagnostics). Additionally, utilization of the AFIAS IL‐6 assay was evaluated.

Methods

The IL‐6 levels from 113 serum samples quantified using two assay systems were evaluated for their degree of correlation. Meanwhile, the linearity, analytical sensitivity, and precision/reproducibility of the AFIAS IL‐6 assay were also assessed.

Results

Quantification of IL‐6 with the AFIAS IL‐6 and Elecsys IL‐6 assays showed excellent agreement (kappa 0.802) and were found to be correlated (y = −0.2781 + 1.068x; 95% confidence interval: 1.007–1.124). AFIAS IL‐6 showed good analytical performances. IL‐6 levels were significantly higher in deceased patients compared to those with non‐complicated disease and those who were intubated (p = 0.002 and p < 0.0001, respectively). Finally, IL‐6 levels more accurately predicted poor prognosis in patients, than did C‐reactive protein (area under the curve, 0.716 vs. 0.634).

Conclusion

The overall analytical performance of the AFIAS assay was comparable to that of the Elecsys IL‐6 assay. In light of the ongoing COVID‐19 pandemic, the AFIAS may be an attractive tool for measuring IL‐6 levels.

Performance evaluation of the Roche cobas 6800 system for quantifying cytomegalovirus DNA in plasma and urine samples

INTRODUCTION

Cytomegalovirus (CMV) nucleic acid amplification testing is important for CMV infection diagnosis and management. CMV DNA is found in plasma and various other fluids, including urine. If CMV can be reliably detected in urine, it may be considered a non-invasive alternative to blood tests. The cobas 6800 system (Roche Diagnostics, Mannheim, Germany) is a Food and Drug Administration-approved testing platform for measuring CMV DNA in plasma.

OBJECTIVE

To evaluate the analytical performance of the cobas 6800 system and compare the clinical feasibility of CMV detection in plasma and urine samples.

STUDY DESIGN

Imprecision, linearity, limit of quantitation (LOQ), and cross-reactivity of the cobas 6800 system were assessed, and reference interval verification was performed. Plasma CMV DNA quantification was compared to CMV DNA values in urine samples obtained from 129 pediatric patients (<18 years of age) from March 2020 to May 2020 at a tertiary hospital.

RESULTS

The assay precision was within the acceptable range. Linearity was observed within the tested concentration range (2.36-6.33 log IU/mL) with a coefficient of determination of 0.9972. The LOQ was 34.5 IU/mL. The assay did not show cross-reactivity with 15 other viruses. Plasma and urine detection results were stratified into three categories: negative, <LOQ, and positive to analyze the degree of agreement with the results. The quadratic weighted kappa value was 0.623 (P = 0.000), showing substantial concurrence.

CONCLUSION

The cobas 6800 system offers good sensitivity, precision, and linearity and is suitable for monitoring CMV viral loads in the plasma and urine samples.

Effects of military life on changes in body mass index of enlisted men: a cross-sectional study

Background

Obesity is a serious health problem with an incidence that is increasing rapidly. Enlisted men are a distinctive group characterised by 24-hour community-living and are likely to experience changes in body weight as a result of regular diet and exercise during enlistment.

Methods

This study reviewed data from the Second Military Health Survey. Changes in body mass index (BMI) before and during military service were analysed using paired t-test. We calculated OR and 95% CI for factors affecting weight improvement during military service through logistic regression.

Results

The mean BMI in the underweight group increased by 5.87 kg/m² during service, while that in the normal weight group increased by 1.18 kg/m². In contrast, the mean BMI in the overweight group decreased by 5.47 kg/m² during service. The OR for an improved BMI in the subjective good health group compared with the subjective poor health group was statistically significant (OR=1.71, 95% CI 1.02 to 2.87). The OR for an improved BMI was significantly higher in the group with three or more times per week of strength training than in the group with one to two times per week of strength training, and was higher among the marines compared with the Army soldiers (OR=1.48, 95% CI 1.03 to 2.12 and OR=2.15, 95% CI 1.07 to 4.32, respectively).

Conclusions

Strength training showed a statistically significant increase in BMI during military service. Furthermore, the BMI of men who were underweight before their service increased, while it decreased among those who were overweight.

Blood Supply and Demand in Korea: What is in Store for the Future?

PURPOSE

Presently, Korea is facing new challenges associated with an imbalance in blood supply and demand. The purpose of this study was to examine trends in blood supply and demand in Korea over the past 10 years through 2018 and to propose what to prepare in the future.

MATERIALS AND METHODS

Age demographics in Korea were analyzed using data from the Statistics Korea. Blood donation and blood supply data were analyzed using Blood Services Statistics 2018 by the Korean Red Cross. Blood transfusion data from hospitals in 2018 were obtained from the Health Insurance Review and Assessment Service.

RESULTS

In 2018, 2883270 whole blood and apheresis units were collected in Korea. The Korean Red Cross supplied 4277762 blood components to 2491 hospitals. The overall blood donation rate was 5.6%, and the most frequent donors were young male donors. Leukoreduced red blood cells (RBCs) constituted 25% of all RBCs used, and 40% of all platelets were supplied by single-donor platelets. The self-sufficiency rate of domestic plasma with which to produce plasma-derived medicinal products was 68.7% in 2018. Blood use was the most frequent among patients aged 70-79 years.

CONCLUSION

Blood management in Korea is changing rapidly due to a low birth rate, rapid aging, and an increase in severely ill patients who require most of the blood supply. Therefore, future plans to promote donation at a national level and optimal use of blood in hospitals is necessary.

Use of Convalescent Plasma Therapy in Two COVID-19 Patients with Acute Respiratory Distress Syndrome in Korea

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 not yet has established its treatment, but convalescent plasma has been expected to increase survival rates as in the case with other emerging viral infections. We describe two cases of COVID-19 treated with convalescent plasma infusion. Both patients presented severe pneumonia with acute respiratory distress syndrome and showed a favorable outcome after the use of convalescent plasma in addition to systemic corticosteroid. To our knowledge, this is the first report of the use of convalescent plasma therapy for COVID-19 in Korea.

Asymptomatic Cerebral Vasoconstriction after Carotid Artery Stenting

BACKGROUND AND PURPOSE

Carotid artery stent placement is widely performed for treatment of carotid stenosis. The purpose of this study is to present our observations on cerebral vasoconstriction in ipsilateral anterior circulation during immediate poststenting angiography in patients with near-total occlusion of the proximal ICA.

MATERIALS AND METHODS

We retrospectively reviewed patient data from December 2008 to December 2018. There were 28 patients with carotid near-total occlusion. Two neuroradiologists reviewed the final cerebral angiographic finding of carotid artery stent placement to evaluate the presence of vasoconstriction or vasodilation.

RESULTS

A total of 28 patients with near-total occlusion (mean ± standard deviation age, 69.0 ± 6.5 years; 92.9% male) were analyzed. Ten patients showed vasoconstriction in the treated territory, and 18 patients did not show vasoconstriction after carotid artery stenting. There were no statistically significant differences in comorbidity, frequency of symptomatic lesions, antiplatelet medication, mean procedure time, and initial NIHSS and baseline modified Rankin scale scores between the 2 groups. However, vasoconstriction is more likely to happen in patients with isolated territory from the contralateral anterior and posterior circulation (66.7% in the isolated territory group and 12.5% in the not-isolated territory group; P < .05). No headache or neurologic deficit was noted in all 10 patients with cerebral vasoconstriction.

CONCLUSIONS

Cerebral vasoconstriction may occur after carotid artery stenting more frequently than expected. It occurs more frequently in patients with near-total occlusion and with isolation of the cerebral circulation. A large-scale study is necessary to assess the clinical implications of cerebral vasoconstriction after carotid artery stenting.

Application of the Whole Genome-Based Bacterial Identification System, TrueBac ID, Using Clinical Isolates That Were Not Identified With Three Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) Systems

BACKGROUND

Next-generation sequencing is increasingly used for taxonomic identification of pathogenic bacterial isolates. We evaluated the performance of a newly introduced whole genome-based bacterial identification system, TrueBac ID (ChunLab Inc., Seoul, Korea), using clinical isolates that were not identified by three matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) systems and 16S rRNA gene sequencing.

METHODS

Thirty-six bacterial isolates were selected from a university-affiliated hospital and a commercial clinical laboratory. Species was identified by three MALDI-TOF MS systems: Bruker Biotyper MS (Bruker Daltonics, Billerica, MA, USA), VITEK MS (bioMérieux, Marcy l'Étoile, France), and ASTA MicroIDSys (ASTA Inc., Suwon, Korea). Whole genome sequencing was conducted using the Illumina MiSeq system (Illumina, San Diego, CA, USA), and genome-based identification was performed using the TrueBac ID cloud system (www.truebacid.com).

RESULTS

TrueBac ID assigned 94% (34/36) of the isolates to known (N=25) or novel (N=4) species, genomospecies (N=3), or species group (N=2). The remaining two were identified at the genus level.

CONCLUSIONS

TrueBac ID successfully identified the majority of isolates that MALDI-TOF MS failed to identify. Genome-based identification can be a useful tool in clinical laboratories, with its superior accuracy and database-driven operations.

336 QUANTITATIVE ANALYSIS OF TETRACYCLINE-INDUCIBLE EXPRESSION OF THE GREEN FLUORESCENT PROTEIN GENE IN TRANSGENIC CHICKENS

The use of transgenic farm animals as bioreactors to address the growing demand for biopharmaceuticals, both in terms of increased quantity and greater number, represents a key development in the advancement of medical science. However, the potential for detrimental side effects as a result of uncontrolled constitutive expression of foreign genes in transgenic animals is a well-recognised limitation of such systems. Previously, using a tetracycline-inducible expression system, we demonstrated the induction of expression of a transgene encoding green fluorescent protein (GFP) in transgenic chickens by feeding with doxycycline, a tetracycline derivative; expression of GFP reverted to pre-induction levels when the inducer was removed from the diet (Kwon et al. 2011 Biochem. Biophys. Res. Commun. 410, 890–894). As a proof of principle study, however, quantitative assessment of expression was not possible, as only 1 G0 and 1 G1 transgenic chicken was obtained. In the current study, with 7 G2 transgenic chickens obtained from 1 G1 hen, we confirmed stable genomic integration of a single copy number of the transgene by Southern blot analysis. As we have observed in G1 transgenic chicken previously, all of the G2 transgenic chickens emitted a green fluorescence upon doxycycline feeding (50 mg kg–1 of formula feed). Fluorescence became detectable 4 days after starting doxycycline feeding, and maximum GFP expression was detected after 2 weeks. Removal of doxycycline from the diet after 14 days of induction feeding resulted in the return of external fluorescence to pre-induction levels after 39 days. Quantitative analysis of gene induction was done using protein and mRNA extracted from primary cultured cells derived from 6-day transgenic chicken embryos. The eggs were obtained by mating a nontransgenic wild-type hen with 1 of G2 transgenic roosters. Protein levels of GFP were analysed by immunoblot and quantified using a densitometer. In the absence of doxycycline, the amount of GFP per 1 µg of total protein was 0.2 ng. However, when the cells were treated with doxycycline for 6 days, the amount of GFP increased to 3.1 ng per 1 µg of total protein, which was 16-fold higher than that of the cells pre-treated with doxycycline. Switching to doxycycline-free medium after doxycycline induction resulted in significant abrogation of GFP expression in 6 days; the amount of GFP reduced from 3.1 to 0.5 ng, a 6.2-fold reduction. Transcription of the GFP gene was also assessed by Northern blot. The amount of GFP mRNA measured by band density increased as much as 20-fold (3.9/0.2) with 6 days of doxycycline induction and declined to 1/8 (3.9/0.5) when doxycycline was removed from the cell culture media for 6 days. The use of an inducible expression system that can be regulated by dietary supplementation could help mitigate the physiological disruption that can occur in transgenic animals as a result of uncontrolled constitutive expression of a transgene.

CYP2C19 haplotypes in Koreans as a marker of enzyme activity evaluated with omeprazole

BACKGROUND AND OBJECTIVE

CYP2C19 is clinically important in Korea because of the relatively high incidence of poor metabolizers in the population. To fully understand the genetic mechanism of the CYP2C19 defect in poor metabolizers, all variants need to be studied simultaneously. The aim of this study was to investigate the usefulness of CYP2C19 haplotypes as a marker of CYP2C19 enzyme activity in Koreans.

METHODS

We analysed the single nucleotide polymorphisms and haplotypes of the CYP2C19 gene in 150 healthy Koreans and found three major (frequency > 0.1) haplotypes (H1, H2 and H3). One oral dose of 40 mg omeprazole (Losec) was administered to 30 subjects grouped as H1/H1, H2/H2, H1/H2, H1/H3 and H2/H3. The pharmacokinetics of omeprazole and its metabolites, 5-hydroxyomeprazole and omeprazole sulphone, in those groups was analysed.

RESULTS AND DISCUSSION

The area under the plasma concentration-time curve (AUC(0-->infinity)) and elimination half-life (T(1/2)) of omeprazole were significantly greater in the H2/H2 and H2/H3 groups than in the H1/H1 group (P < 0.05), whereas the metabolic ratios of omeprazole to 5-hydroxyomeprazole were also markedly higher.

CONCLUSION

Although a specific SNP of CYP2C19 may be predictive of enzyme activity, haplotyping is more reliable for identifying poor metabolizers in populations with variant alleles other than CYP2C19*2 and *3 alleles.

Clinical outcome of sequential chemotherapy in metastatic and/or recurrent gastric cancer

e15521

Background: Little is known about data on subsequent chemotherapy (CTx) following 1st-line CTx in stage IV gastric cancer. The purpose of this study was to analyze the natural history of stage IV gastric cancer with sequential CTx Methods: A total of 532 patients (pts) with unresectable gastric adenocarcinoma were studied. They were managed with a strategy of maximal administration of CTx only if pts’ general conditions were allowed. Response evaluation was performed by RECIST every 2 cycles. Response of unmeasurable lesions was dichotomized only into stable disease or progressive disease. Results: When pts were divided into CTx group (460 of 532, 87%) and best supportive care group (BSC; 72 of 532, 13%) resulting from poor performance/pt's refusal/comorbidity (31/23/18), the former had younger age (p = 0.046), better performance (p < 0.001), and less advanced metastatic sites (p = 0.001) than the latter. Median overall survivals from diagnosis of unresectable cancer were 12.0/13.3/2.5 months for overall/CTx/BSC, respectively. 87%/47%/23% of the whole pts received 1st/2nd/3rd-line CTx, respectively. Median number of regimens delivered was 2. Maximally 5th-line CTx was given to 15 pts (3%). Response and disease control rates were 21.7%/12.5%/11.8% and 79.4%/56.3%/49.4% for 1st/2nd/3rd lines, respectively. Median progression-free and overall survivals from CTx were 5.5/3.4/2.5 months and 12.1/7.9/5.5 months for 1st/2nd/3rd lines, respectively. The most common cause of discontinuation of CTx was disease progression (68%/74%/70%) followed by pt's refusal (22%/13%/12%) for 1st/2nd/3rd lines, respectively. Prognosticators were performance status, histology, metastatic site, and CTx before 1st or 2nd line. Conclusions: When pts with unresectable gastric cancer were managed with a strategy of maximal administration of CTx, a considerable number of pts could receive 2nd or 3rd line CTx, showing modest activity. Performance status and metastatic site were consistent prognosticators even if lines changed. Our data on the natural history of stage IV gastric cancer with sequential CTx may suggest that clinical trials can be performed in a 2nd or 3rd line setting as well.

No significant financial relationships to disclose.

Comparison of long-term outcome between doublet versus triplet neoadjuvant chemotherapy in nonmetastatic osteosarcoma of extremity

10542

Background: Multimodal approach had improved outcomes of non-metastatic osteosarcoma. This study was to compare outcomes between doublet (AP; doxorubicin and cisplatin) and triplet (IAP; AP and ifosfamide) neoadjuvant chemotherapy for non-meteastatic osteosarcoma of extremity in a single institute. Methods: A total of 124 osteosarcoma patients were enrolled. In AP group, doublet regimen was given to 77 patients from 1991 to 1999, who received intra-arterial cisplatin(120mg/m2) at day 1 and intravenous doxorubicin (25mg/m2) for 3 days. In IAP group, triplet regimen was given to 49 patients from 2000 to 2007, who received ifosfamide additionally at a dose of 2.5g/m2/day for 3 days. After completion of 3 cycles of chemotherapy, patients underwent limb-salvage surgery. We assessed tumor response according to pathologic tumor necrosis, and treated further adjuvant chemotherapy. In AP group, responder received 3 more cycles of AP, while non-responders received 6 cycles of ifosfamide-contaning regimens. In IAP group, all patients had 3 more cycles of IAP chemotherapy. Results: The median follow-up duration was 5.2 years (0.4–16.7). The most frequent site and histology were distal femur and osteoblastic type. Overall pathologic response was more than 90% tumor necrosis in 74.8% of patients. Total necrosis of tumor was also found in 46 patients (37.4%). There was no difference between two groups in pathologic response (76.3% vs. 72.3%; p=0.62) or other clinico-pathologic parameters. Tumor recurrence was occurred in 31.5% of patients with the most common site of lung (84.6%). There was no difference between two groups in recurrence (p=0.17) or lung metastasis (p=0.53). There were no statistical differences in disease free survival (p=0.75) and overall survival (p=0.07) between two groups. In toxicity profiles, there were more hematologic toxicity in IAP group (febrile neutropenia,p<0.001; thrombocytopenia,p<0.05), while there were no statistical differences in treatment related death. Conclusions: The addition of ifosfamide to doxorubicin and cisplatin in neoadjuvant chemotherapy did not show improved outcomes in this study. Further trials are required to elucidate optimal neoadjuvant chemotherapy and effective salvage regimens.

No significant financial relationships to disclose.

Predictive factors associated with clinical outcome and safety in Korean patients with metastatic renal cell carcinoma treated with sunitinib

e16111

Background: Sunitinib has become a standard treatment for metastatic renal cell carcinoma (RCC). The research for identifying patients who are more likely to benefit from this agent is quite limited, especially in Asian patients. Methods: In total, 81 histologically proven metastatic RCC patients who were treated with sunitinib were reviewed between Jan 2006 and Dec 2008. Tumor response was evaluated according to the RECIST criteria, and safety was assessed by NCI-CTC (version 3.0). Primary endpoint was progression-free survival (PFS) and secondary endpoints included overall survival (OS), overall response rate (ORR), disease control rate (DCR), and toxicities. Clinical features associated with clinical outcome were identified by univariate analysis; then, a stepwise modeling approach based on Cox's proportional hazards regression was used to identify independent prognostic factors to these endpoints. Results: Median age was 58 years (range, 29 to 73), and 33 patients received sunitinib as first-line systemic treatment. Clear cell type was predominant (85%). Patient distribution was 12% for favorable, 78% for intermediate, and 10% for poor group according to the MSKCC risk group. With the median follow-up of 26 months, median PFS was 16 months (95% CI, 8 –24) and median OS was 24 months (95% CI, 18 –30). ORR was 30% (95% CI, 19–40%) and DCR was 80% (95% CI, 70–89%). The most common grade 3/4 adverse events of sunitinib was thrombocytopenia (32%). Other severe toxicity included neutropenia (21%), anemia (19%), leucopenia (14%), fatigue (10%), stomatitis (10%). In multivariate analysis, the previous exposure to immunotherapy was related to longer PFS (P<.012). Performance status (ECOG 0–1) and corrected Ca level (8.5∼10.5 mg/dl) were associated with favorable ORR (P=.038) and DCR (p=0.008), respectively. Predictive factors for grade 3/4 thrombocytopenia were corrected Ca level (P=.018), poor MSKCC risk group (P=.025), and low WBC count (<4500/ul, P=.041). Conclusions: Compared to western reports, our data demonstrated comparable clinical efficacy in Asian patients, but different safety profile, especially in hematologic toxicities. This approach provides a tailored approach to predictive factors for targeted agents.

No significant financial relationships to disclose.

304 PRODUCTION OF TRANSGENIC CHICKENS EXPRESSING HUMAN ERYTHROPOIETIN IN A TETRACYCLINE-INDUCIBLE MANNER

The use of livestock animals as bioreactors to address the growing demand for large quantities and increasing numbers of biopharmaceuticals is of prime strategic relevance to agricultural improvement and medical advancement. We report here the production of transgenic chickens that produce human erythropoietin (hEPO) using replication-defective Moloney murine leukemia virus-based vectors. Because it is well known that constitutive overexpression of some cytokine genes in the transgenic animals may cause serious physiological disturbances, the vectors were designed to express in the presence of tetracycline. In addition, we introduced woodchuck hepatitis virus posttranscriptional regulatory element sequence at 3′ end of hEPO gene to boost the gene expression under the inducible condition. Approximately 5 μL of vector virus solution concentrated as much as 109 cfu mL–1 was injected beneath the blastoderm of non-incubated chicken embryo (stage X). Out of 596 injected eggs, 36 chicks hatched after 21 days of incubation and 23 hatched chicks were found to express vector-encoded hG-GSF gene when fed with doxycycline. Quantitative analysis of the blood samples taken from some Go transgenic chickens resulted in more than 300 IU mL–1 of hEPO in the blood. These transgenic chickens have not exhibited any physiological abnormalities; therefore, it is possible that this controllable gene expression system may be useful in minimizing detrimental side effects when used to produce other transgenic animals. The biological activity of the recombinant hEPO was comparable to its commercially derived Escherichia coli counterpart. The significance of this work stems from the fact that it is the first successful report on the production of transgenic chickens expressing the hEPO gene. This approach can be employed to create a useful transgenic model system for further studies on the chicken embryo development and the efficient production of transgenic chickens as bioreactors. This work was supported by: The BioGreen 21 Program of the Rural Development Administration, Republic of Korea; The SRC/ERC program of MOST/KOSEF (grant no. R11-2002-100-04005-0); The 2006–2011 Technology Development Program for Agriculture and Forestry (TDPAF), Ministry of Agriculture and Forestry, Republic of Korea.

Phase I trial of neoadjuvant concurrent chemoradiotherapy with S-1 and weekly irinotecan in locally advanced rectal cancer

14543

Background: S-1 is a novel, orally administered 5-FU analogue and is known of radiosensitizer. The aim of this study was to establish the feasibility and efficacy of S-1 in combination with weekly irionotecan with concurrent pelvic radiotherapy (RT) in patients with locally advanced rectal cancer. Methods: Clinical stage T3–4 or N+(on MRI) rectal adenocarcinoma patients received weekly irinotecan 40mg/m2(day1,8,15,22,29) and S-1 at dose levels of 40, 50, 60 and 70mg/m2 (5days a week from day 1 to 38) according to phase I methodology. Concurrently conventional RT was given at daily fractions of 1.8 Gy on 5 days a week for a total dose of 50.4 (45 + 5.4)Gy. Surgery was performed 4–8 weeks following completion of chemoradiation. Results: A total 16 patients (10M/7F, median age 46 years, ECOG PS0–1) were enrolled between August 2005 and July 2006. One pt withdrew the consent during CCRT. Dose-limiting toxicity (DLT) occurred at 50mg/m2 of S-1 in one of six pts (G4 cerebral infarction). At dose of 60, 70mg/m2 of S-1, no DLT occurred. G3/4 toxicties were rare. Fifthteen pts underwent surgery and R0 resection was achieved in 13 pts. Four pts (25.0%) had a pathological complete response. Conclusions: The recommended dose (RD) for further study is S-1 70mg/m2 with irinotecan and radiotherapy. Neoadjuvant S-1/irinotecan/RT is feasible and well tolerated. Phase II trial is being conducted.

No significant financial relationships to disclose.

Mobilized circulating endothelial progenitor cells after the first cycle of chemotherapy with prophylactic G-CSF can be used as a predictive biomarker and patient selection marker for anti-angiogenesis combination treatment

4638

Background: We investigated whether the level of circulating endothelial progenitor cells (CEPs) and endothelial cells (CECs) could be used as surrogate predictors of clinical outcome in patients receiving taxotere-based chemotherapy for advanced gastric cancer. Methods: Peripheral blood mononuclear cells were obtained in 49 gastric cancer patients who received taxotere combined with 5-FU and leucovorine (FLT regimen) after chemotherapy and prophylactic G-CSF treatment. To categorize the endothelial cells, immunofluorescent staining for specific endothelial cell markers (CD34, vWF, P1H12, CD31) was used. The changes of CEPs and CECs and their clinical significance on the response prediction and prognosis were analyzed. Results: After the first cycle of chemotherapy, the numbers of CD34+/vWF+, CD34+, vWF+, P1H12+ and CD31+ cells of 49 patients were 19.5 (2.7% of PBMCs), 20.1 (2.7%), 30.0 (4.8%), 12.9 (2.7%) and 214.3 (26.5%) cells/ml, respectively. The number of CD34+/vWF+ and CD34+ cells after the first and second cycle of chemotherapy were found to be higher in non-responders than responders (the first cycle: P=.012 and P=.008, the second cycle: P=.027 and P=.013, respectively). Moreover, the level of CD31+ cells after the second cycle of chemotherapy were significantly decreased compared with the first cycle in the patients who showed response (P=.026). In non-responders, however, the level of CD34+ cells was significantly increased after the second cycle of chemotherapy (P=.034). The level of CD34+ cells significantly related to the median time to progression (TTP) (6.1 and 4.0 months in CD34low and CD34high, respectively, cutoff level: 5.8, P=.046). Conclusion: CD34+/vWF+ and CD34+ cells can be used as a biomarker for prediction and prognosis in taxotere-based chemotherapy. CEP after the first cycle of chemotherapy can be a selection marker for addition of anti-angiogenic treatment after chemotherapy.

No significant financial relationships to disclose.

Rehabilitative orthotics evaluation in children with diplegic cerebral palsy: kinematics and kinetics

Ankle foot orthoses (AFOs) are prescribed for ambulatory children with spastic diplegia to improve biomechanical alignment and functional capability. The purpose of this study was to employ quantitative motion analysis of the lower extremity to investigate two rehabilitative orthotics. The effects of hinged ankle foot orthoses (HAFO) and dynamic ankle foot orthoses (DAFO) for joint ankle management in children with cerebral palsy were compared. Sixteen (16) independently ambulatory children with a diagnosis of spastic diplegic cerebral palsy (7.5 +/- 2.9 yrs.) were included in the study. The biomechanical effects of two AFO designs were compared to barefoot using a 3-D motion analysis system. Significant differences between braced and unbraced conditions were found in peak ankle dorsiflexion, and peak ankle plantarflexion, knee stance peak flexion, knee swing peak flexion, hip stance peak flexion, and peak ankle plantarflexion moment (p < 0.01). Differences between the HAFO and DAFO were not seen in the kinematic and kinetic metrics. Further development of dynamic testing is suggested in order to advance our understanding of orthotic intervention. The value of quantitative description of gait dynamics is clearly indicated for rehabilitative application.

Chemoradiation and maintenance chemotherapy with cisplatin and 5-fluorouracil in anal squamous cell carcinoma

14057

Background: Chemoradiation is the standard treatment for anal carcinoma. Mitomycin-C (MMC) with 5-fluorouracil (5-FU) is the widely used regimen, but MMC is not a radiation sensitizer and has significant toxicities. This study was conducted to update our experience in treating anal carcinomas with an external beam radiation and continuous infusion of 5-FU with cisplatin. Methods: Twenty-eight patients with locally advanced squamous cell carcinoma of the anus were treated between 1995 and 2005. The primary tumor and involved lymph nodes received a total of 41.4–64.8 Gy and 39.6–60.4 Gy, respectively. Chemotherapy consisted of 5-FU (1,000 mg/m2 CI, D1–5 and D36–40) and cisplatin (80 mg/m2 IVF, D2 and D37) q 4weeks for 4 courses. Results: One patients had T1 lesions, 15 had T2, 7 had T3, and 5 patients had T4 disease. Seventeen patients presented with clinically detectable lymphadenopathy. Eight patients failed to start maintenance chemotherapy due to events during chemoradiation. Of the 19 patients who started maintenance chemotherapy, 3 failed to complete all four courses due to intolerance to chemotherapy. With a median follow-up duration of 68.5 months, the actuarial 5-year OS rate was 83.2 %, the DFS rate 80.7%, and the colostomy-free survival was 91.7%. Patterns of recurrence were local relapses in 3 patients, distant metastases in 2, and both in 1, respectively. Seventeen patients (60.7%) developed moist skin reaction, which frequently caused the interruption of radiotherapy. Principal grade 3/4 hematologic toxicities were neutropenia in 10 patients (35.8%) and thrombocytopenia in 4 (14.2%). The most common late complications were lymphedema (14.3%). Conclusions: Our results demonstrate that combined modality therapy with external beam radiation, cisplatin and 5-FU yields an excellent outcome in terms of survival and sphincter preservation which is comparable to the results of MMC regimens.

No significant financial relationships to disclose.

Phase II study of oral S-1 monotherapy in metastatic colorectal cancer after failure of both irinotecan and oxaliplatin-containing regimen

3597

Background: There has been a considerable increase in the number of patients (pts) with mCRC pretreated with both irinotecan and oxaliplatin. Little is known about third-line therapy in this group of pts. We conducted a phase II trial of oral S-1 in pts with advanced colorectal cancer who failed on both irinotecan and oxaliplatin. Methods: This phase II study was designed to evaluate the activity and toxicity of S-1 monotherapy in 31 advanced colorectal cancer pts (P0 = 3%, P1 = 15%; α = 0.05, power = 80%, drop-out rate 10 %). S-1 was administered orally twice daily, 70 mg/m2/day for 14 days followed by 1-week rest. Eligibility criteria included ECOG 0–2; measurable lesion; adequate organ functions; signed informed consent. Results: As of 1st September 2005, 21 pts were enrolled. Median age of all pts 55 years. There were 10 male and 11 females. Thirteen of 21 patients were treated with oxaliplatin-containing regimens as a first-line therapy for metastatic diseases. The median number of treatments was 3 courses (range, 1–10). The relative dose intensity was 1.0 (0.83 - 1.0) with a median dose of120 mg (100 -140 mg). Nineteen out of 21 patients were evaluable. The confirmed response rate was 21.1% (4/19, 1 CR, 3 PR). The median PFS was 11 weeks, and median OS was not reached. The most frequent adverse reaction was skin pigmentation (47.6%). Grade 3 toxicities was skin pigmentation in 1 patients (4.8%), neutropenia in 1 (4.8%), and anemia in 1 (4.8%), respectively. Conclusion: This results shows that S-1 produces a promising response rate with an acceptable safety profile in refractory, mCRC. S-1 has the potential to become a valuable option as a third-line salvage regimen in irinotecan and oxaliplatin pretreated mCRC pts. Clinical trial of combination therapy with S-1 will be warranted.

No significant financial relationships to disclose.