Characteristics of Graft-Versus-Host Disease (GvHD) After Post-Transplantation Cyclophosphamide Versus Conventional GvHD Prophylaxis

Post-transplantation cyclophosphamide (PTCy) has been shown to effectively control graft-versus-host disease (GvHD) in haploidentical (Haplo) transplantations. In this retrospective registry study, we compared GvHD organ distribution, severity, and outcomes in patients with GvHD occurring after Haplo transplantation with PTCy GvHD prophylaxis (Haplo/PTCy) versus HLA-matched unrelated donor transplantation with conventional prophylaxis (MUD/conventional). We evaluated 2 cohorts: patients with grade 2 to 4 acute GvHD (aGvHD) including 264 and 1163 recipients of Haplo and MUD transplants; and patients with any chronic GvHD (cGvHD) including 206 and 1018 recipients of Haplo and MUD transplants, respectively. In comparison with MUD/conventional transplantation ± antithymocyte globulin (ATG), grade 3-4 aGvHD (28% versus 39%, P = .001), stage 3-4 lower gastrointestinal (GI) tract aGvHD (14% versus 21%, P = .01), and chronic GI GvHD (21% versus 31%, P = .006) were less common after Haplo/PTCy transplantation. In patients with grade 2-4 aGvHD, cGvHD rate after Haplo/PTCY was also lower (hazard ratio [HR] = .4, P < .001) in comparison with MUD/conventional transplantation without ATG in the nonmyeloablative conditioning setting. Irrespective of the use of ATG, non-relapse mortality rate was lower (HR = .6, P = .01) after Haplo/PTCy transplantation, except for transplants that were from a female donor into a male recipient. In patients with cGvHD, irrespective of ATG use, Haplo/PTCy transplantation had lower non-relapse mortality rates (HR = .6, P = .04). Mortality rate was higher (HR = 1.6, P = .03) during, but not after (HR = .9, P = .6) the first 6 months after cGvHD diagnosis. Our results suggest that PTCy-based GvHD prophylaxis mitigates the development of GI GvHD and may translate into lower GvHD-related non-relapse mortality rate.

Abstract 19 Cleveland Cord Blood Center (CCBC) Best Practices Throughout the COVID-19 Pandemic and How It Impacted Collection of Cord Blood Units

Introduction

Our commitment to provide quality cord blood units (CBUs) to patients in need was challenged with the outbreak of COVID-19 and the pandemics continued impact through early 2022. We continually monitored the ever-evolving COVID-19 public health threat to make adjustments to our practices to achieve optimal collections while maintaining the safety and quality of our CBUs.

Objective

The CCBC continued collections at all five collection sites with a brief mandated pause at our California site due to hospital restrictions. We maintained minimal staffing at the cord blood center to reduce the number of employees impacted should an exposure occur. Donors were screened upon admission for symptoms, exposure, positive testing, and recent vaccination, and donors with identified risks were excluded from collection.

Methods

Our study design takes a retrospective look at data collected from the onset of the COVID-19 pandemic through December 2021 compared to data from 2018-2019. Factors included were birth numbers, number of patients testing positive for COVID-19, and staffing shortages due to coordinator illness with COVID-19.

Results

We saw limited impact to our collection staff at the hospital or on site at the CCBC. Our biggest reduction of donors consented was between 2019 and 2020, which we attribute to the COVID peak and introduction of vaccinations. Most sites were trending downward for consenting on a yearly basis before COVID-19 at a rate of 6%-10% per year; during 2019-2020 we saw 19%, but the trend has returned to 8% from 2020-2021. This same trending occurred during the ZIKA outbreak. There was no further data review to determine if these mothers would have been excluded for other reasons. We collected a total of 15,561 units between 2018 and 2019 and a total of 10,121 units between 2020 and 2021.

Discussion

Overall productivity of the collections was not dramatically affected by our response to the COVID-19 pandemic. Further research at time of pre-consent, to determine if the mother would have been ineligible to donate for reasons other than COVID-19, would have given us a more accurate count of donors lost for reasons related to the COVID-19 pandemic.

Umbilical cord derived monocytes and platelet rich plasma for diabetic wound healing

Chronic non-healing ulcers are a significant complication present in approximately 15% of diabetic patients. Despite standard clinical treatment including wound dressing, debridement of necrotic tissue, and offloading, 15–27% of patients with diabetic ulcer will require amputation. Deep infection is a risk factor for amputation. Platelet rich plasma (PRP) and stem cells have been tested for potential application to treat diabetic ulcers and have been shown to improve wound healing. Umbilical cord blood provides robust cellular and secreted products with therapeutic potential, but remains yet to be fully exploited as a resource for wound healing strategies. Our initial proof of concept studies indicate that umbilical cord blood derived monocytes and platelet rich plasma enhance wound healing processes measured by in vitro assays. When compared to monocytes or platelet rich plasma alone, monocytes and platelet rich plasma significantly enhanced neovascularization as measured by the matrigel angiogenesis assay. Monocytes and platelet rich plasma enhanced fibroblast migration in a wound scratch assay. Additionally, monocytes and platelet rich plasma enhance proliferation of endothelial cells and fibroblasts. Furthermore, these monocytes have potent antibacterial effects as measured by their ability to phagocytose P. aeruginosa in vitro. Collectively, this in vitro data indicates that this product could heal wounds by a mechanism involving enhancing neovascularization, proliferation, migration, and antibacterial activities, all processes which are dysregulated in diabetic wound healing.

Posaconazole Pharmacokinetics, Safety, and Tolerability in Subjects With Varying Degrees of Chronic Renal Disease

Posaconazole is a triazole antifungal in development for the treatment of invasive fungal infections. The authors evaluated the pharmacokinetics and safety of posaconazole in healthy subjects and in those with mild (CL(CR) = 50-80 mL/min), moderate (CL(CR) = 20-49 mL/min), and severe chronic renal disease (CL(CR) <20 mL/min; receiving outpatient hemodialysis) (n = 6/group). Subjects received one 400-mg dose of posaconazole oral suspension with a standardized high-fat breakfast. For hemodialysis-dependent subjects, this dose was given on a nonhemodialysis day, and a second 400-mg dose was given 6 hours before hemodialysis. Blood samples were collected before dose and up to 120 hours postdose. For hemodialysis-dependent subjects following the second dose, additional samples (predialyzed and postdialyzed) were collected before, during, and after dialysis. There was no correlation between posaconazole pharmacokinetics and mild to moderate renal disease; the slopes of the linear regressions for creatinine clearance versus posaconazole AUC, C(max), CL/F, and t1/2 values were not significantly different from zero (P > .130). Mean CL/F values before and during hemodialysis were comparable. Furthermore, the difference in the predialyzed and postdialyzed posaconazole concentrations was only approximately 3%, supporting that posaconazole was not removed by hemodialysis. Protein binding was similar in all groups (approximately 98%) and was unaffected by hemodialysis. Posaconazole was generally well tolerated. One patient had elevated liver function test results that were not present at baseline and were thought to be possibly related to posaconazole. Results of this single-dose study indicate that dosage adjustments for patients with varying degrees of renal disease are not required.

Repression of NFAT1 protein expression by MicroRNA-184 in umbilical cord blood (UCB) CD4+ T-cells as a potential mechanism underlying lower incidence of acute graft-vs-host disease (aGVHD) (145.36)

Lower expression of the transcription factor NFAT1 in UCB CD4+ T-cells compared to adult blood (AB) results in reduced inflammatory cytokine production after stimulation, in part underlying its advantages in unrelated transplant. Fractionation and RT-PCR reveal that NFAT1 is translationally repressed in UCB during early stimulation, which may be due to microRNA. microRNA queries reveal that miR-184 is strongly predicted to bind to the NFATc2 3’ untranslated region (UTR). In UCB, insertion of the miR-184 binding site into the luciferase 3’ UTR reduced expression by 62% and the full 3’ UTR by 40%. Both these effects were reversible by cotransfection with excess of blocking antisense to miR-184. The UTR did not impact luciferase expression in AB CD4+ T-cells, but both luciferase expression and NFAT1 protein were reduced in AB by a miR-184 mimic in separate analyses, also reversible by cotransfection of antisense. This antisense increased NFAT1 protein expression in UCB CD4+ T-cells as measured by Western Blot without reducing NFATc2 mRNA. qRT-PCR confirmed that miR-184 is expressed 58.4-times greater in UCB than in AB CD4+ T-cells, possibly due to methyl-CpG DNA-binding proteins. We also demonstrated that the effects of miR-184 on NFAT1 are sufficient to alter transcription of the NFAT-dependent cytokine IL-2. This work may hold implications for understanding GVHD, neonatal lymphocyte activation, and suggest miR-184 as a useful biomarker or target of ex vivo graft analysis.

Antiangiogenic activity of thalidomide in combination with fludarabine, carboplatin, and topotecan for high-risk acute myelogenous leukemia

Forty-two patients with poor prognosis AML were enrolled in a phase II study combining fludarabine, carboplatin, and topotecan (FCT) with thalidomide. Laboratory correlates included serum vascular endothelial growth factor levels (VEGF) and bone marrow microvascular density (MVD). Ten of 42 (24%) patients achieved a complete remission (CR or CRp). Serious thrombotic adverse events were observed in 5 patients suggesting that the combination of cytotoxic chemotherapy and thalidomide may be thrombogenic despite significant thrombocytopenia. VEGF did not correlate with response to therapy, while a trend towards decreased MVD was noted in patients who achieved CR. The addition of thalidomide did not significantly influence angiogenic markers. It is not clear that thalidomide adds any efficacy to the FCT regimen.

Molecular analysis of alloreactive CTL post-hemopoietic stem cell transplantation

The development of laboratory tests for the diagnosis and monitoring of graft-vs-host disease (GVHD) is hampered by a lack of knowledge of minor histocompatibility Ags triggering alloresponses. We hypothesized that the unique molecular structure of the TCR could be used as a marker for the unidentified Ags and exploited for molecular monitoring of GVHD posttransplant. To identify alloreactive T cell clones, we performed in vitro allostimulation cultures for a cohort of patients undergoing hemopoietic stem cell transplantation and determined the sequence of the CDR3 of immunodominant alloreactive clones; 10 corresponding clonotypes restricted to activated T cells were identified. As an alternative method for the identification of alloreactive clones, molecular TCR analysis was applied to biopsies of GVHD-affected tissues. Culture- and biopsy-derived clonotypes were used to design sequence-specific quantitative PCR assays to monitor the levels of putative allospecific clonotypes in posttransplant blood samples and subsequent biopsies. Because of the rational design of the methods used to identify immunodominant clonotypes, we were able to follow the behavior of potentially GVHD-specific T cells during the transplant course. Based on our results, we conclude that molecular T cell diagnostics can be a powerful tool for monitoring immune responses posttransplantation.

Two phase 1 studies of MPC-6827, a novel vascular disrupting agent (VDA), in patients with advanced solid tumors and CNS metastases

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Background: MPC-6827 is a novel competitive inhibitor of tubulin polymerization via the colchicine binding site and functions as a highly potent (1–10nM) cytotoxic agent and as a VDA. MPC-6827 inhibits tumor cell growth and survival in vitro and in vivo, with activity in xenograft models of mouse melanoma and human cancers of the ovary, breast, prostate, colon and pancreas. The compound is not a substrate for multidrug resistance pumps and reaches high CSF concentrations. Methods: Two 3+3 designed dose-escalating Phase 1 studies were conducted to define the safety, tolerability, maximum tolerated dose (MTD) and PK of weekly IV administrations of MPC-6827 for pts with advanced solid malignancies (trial 1; N=46 pts) and measurable CNS involvement (trial 2; N=17 pts). In trial 2, there was intrasubject dose escalation for the first cycle and subsequent cycles were dosed at the highest dose achieved in Cycle 1. Antitumor activity was evaluated by RECIST guidelines in both studies. Results: Dose escalation proceeded until MTD was determined at 3.3 mg/m2. The dose limiting toxicity was acute coronary syndrome. Common mild to moderate toxicities included fatigue, headache, flushing, diarrhea, nausea, vomiting and arthralgias. There were no neurological deficits observed and no evidence of myelosuppression. No objective responses were observed. Radiographic changes consistent with vascular disruption in tumors were documented in a number of subjects at higher doses. Conclusions: MPC-6827 is safe and overall well tolerated. MTD is 3.3 mg/m2. Vascular flow modulation analyses are ongoing. MPC-6827 is currently in Phase 2 development.

No significant financial relationships to disclose.

Phase II study of enzastaurin, a protein kinase C beta inhibitor, in patients with relapsed or refractory diffuse large B-cell lymphoma

PURPOSE

Protein kinase C beta (PKCbeta) was identified by gene-expression profiling, preclinical evaluation, and independent immunohistochemical analysis as a rational therapeutic target in diffuse large B-cell lymphoma (DLBCL). We conducted a multicenter phase II study of a potent inhibitor of PKCbeta, enzastaurin, in patients with relapsed or refractory DLBCL.

PATIENTS AND METHODS

Enzastaurin was taken orally once daily until disease progression or unacceptable toxicity occurred. Study end points included freedom from progression (FFP) for > or= two cycles (one cycle = 28 days), objective response, and toxicity.

RESULTS

Fifty-five patients (median age, 68 years) were enrolled. Patients had received a median number of two prior therapies (range, one to five); six patients relapsed after high-dose therapy and autologous stem-cell transplantation. Only one grade 4 toxicity (hypomagnesemia) occurred. Grade 3 toxicities included fatigue (n = 2), edema (n = 1), headache (n = 1), motor neuropathy (n = 1), and thrombocytopenia (n = 1). No grade 3 or 4 neutropenia occurred. No deaths or discontinuations due to toxicity were reported. Fifteen patients completed less than one cycle of therapy. Twelve of 55 patients (22%; 95% CI, 13% to 46%) experienced FFP for two cycles, and eight patients remained free from progression for four cycles (15%; 95% CI, 6% to 27%). Four patients (7%; 95% CI, 2% to 18%), including three complete responders and one patient with stable disease, continue to experience FFP 20+ to 50+ months after study entry.

CONCLUSION

Treatment with enzastaurin was well-tolerated and associated with prolonged FFP in a small subset of patients with relapsed or refractory DLBCL. Further studies of enzastaurin in DLBCL are warranted.

Phase I/II clinical trials for relapsed elderly acute leukemia patients: Importance of performance status at re-induction. A single center retrospective experience

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Background: Relapsed/refractory acute leukemia patients (pts) have a poor outcome and should be considered for enrollment on clinical trials. Elderly (≥ 60 yr) acute leukemia patients often are excluded from phase I/II cytotoxic agent re-induction chemotherapy trials due to concerns for treatment-related toxicity. Methods: Pts with relapsed/refractory acute leukemia who were enrolled on three consecutive phase I/II clinical trials at University Hospitals of Cleveland were evaluated for outcome data including complete response (CR), serious adverse events, and overall survival (OS). Outcome data was compared for pts age ≥ 60 yr versus < 60 yr. Pts with ECOG Performance Status (PS) 0 to 3 were eligible and there was no age limitation. Results: Between 1994 and 11/2005, 96 acute leukemia pts median age 60 yr (range 19–78) were enrolled: 29 pts received phase I topotecan-etoposide; 31 pts received phase I fludarabine, carboplatin, and topotecan (FCT); and 37 pts received phase II FCT plus thalidomide. In univariate analysis, PS at therapy initiation, mean # prior treatments, and disease status at time of treatment were not statistically different between older and younger pts ( Table ). Using Kaplan-Meier method, early treatment-related mortality and OS were similar in pts age ≥ 60 yr compared to pts < 60 yr ( Table ). Mean # ≥ grade 3 toxicities and CR also were similar in both groups ( Table ). In univariate (p = 0.001) and multivariate (p = 0.0004) analyses by Cox modeling, pts PS 0–1 had better OS than PS 2–3 (PS 0–1: 30-day survival 98% and 1 yr survival 24% versus PS 2–3: 30-day survival 81% and 1 yr survival 6%). Conclusions: Poor PS is an important negative predictor of outcomes in relapsed/refractory acute leukemia pts. Advanced age should not exclude pts from cytotoxic re-induction chemotherapy trials.

[Table: see text]

No significant financial relationships to disclose.

Umbilical cord blood transplantation in adults: results of the prospective Cord Blood Transplantation (COBLT)

The Cord Blood Transplantation study group conducted a prospective study of unrelated cord blood transplantation (CBT) to better define the role of this stem cell source for subjects requiring unrelated allogeneic transplantation. We report on 1 stratum of the study designated for adult subjects. The primary end point of the study was survival at 180 days. Secondary end points included engraftment, graft-versus-host disease, relapse, and long-term survival. Eligibility criteria for malignant and nonmalignant diseases were specified. Subjects with active central nervous system disease, Karnofsky performance status <70%, grade 3 or 4 or primary myelofibrosis, or suitable related donors were excluded. Enrollment required a single cord blood unit containing >10(7) nucleated cells per kilogram of recipient weight and matched at > or =4 HLA-A and -B (low or intermediate resolution) and -DRB1 (high resolution) types. Thirty-four subjects were entered, with a median age of 34.5 years (range, 18.2-55 years). Most subjects (n = 23) had a 4 of 6 match, 10 subjects had a 5 of 6 match, and 1 subject had a 6 of 6 match. Diagnoses at transplantation included acute myelogenous leukemia (n = 19), acute lymphoblastic leukemia (n = 9), chronic myelogenous leukemia (n = 3), myelodysplastic syndrome (n = 1), paroxysmal nocturnal hemoglobinuria (PNH) (n = 1), and non-Hodgkin lymphoma (n = 1); 94% were classified as poor risk according to National Marrow Donor Program criteria. Subjects received total body irradiation/cyclophosphamide (n = 27) or busulfan/melphalan (n = 7) conditioning regimens. Four subjects died before CBT and are described here but are not included in the main analysis. The cumulative incidence rates and median times to neutrophil (500/microL) and platelet (>20,000/microL) engraftment were 0.66 by day 42 (median, 31 days) and 0.35 by day 180 (median, 117 days). The cumulative incidence rate for grade II-IV GVHD was 0.34 by day 100. For the primary end point, survival at 180 days, Kaplan-Meier survival estimates were 0.30 (95% confidence interval, 0.14-0.46) by day 180 after transplantation. To date there are 2 survivors, and both are >36 months from enrollment. A retrospective analysis was performed by using high-resolution HLA-A and -B typing, which revealed that approximately one third of subjects had 1 or more additional HLA mismatches compared with results of low- or intermediate-resolution HLA typing. The findings of high treatment-related mortality and slow engraftment kinetics indicate that CBT should continue to be performed in specialized centers with a research focus on cord blood cells.

Unrelated umbilical cord blood transplantation in adult patients

Since January 1996, we have administered myeloablative therapy followed by infusion of unrelated umbilical cord blood cells in 57 adult patients with high-risk disease. The median age was 31 years (range, 18-58 years), and the median weight was 70 kg (range, 46-110 kg). Two patients were treated for genetic disorders and 55 for advanced hematologic malignancies. The preparative regimens were total body irradiation or busulfan based, both with antithymocyte globulin. HLA matching between donor and recipient was 3 of 6 in 3 patients, 4 of 6 in 44 patients, 5 of 6 in 8 patients, and 6 of 6 in 2 patients. The median nucleated cell dose was 1.50 x 10(7)/kg (range, 0.54-2.78 x 10(7)/kg), and the median CD34(+) cell dose was 1.37 x 10(5)/kg (range, 0.02-12.45 x 10(5)/kg). All patients received granulocyte colony-stimulating factor after transplantation until neutrophil recovery. Graft-versus-host disease prophylaxis consisted of cyclosporine and steroids. The median number of days to an absolute neutrophil count of 500/microL was 26 (range, 12-55 days). The median time to an untransfused platelet count of >20000/microL was 84 days (range, 35-167 days). Seventeen patients developed grade II to IV acute GVHD. The median survival of the entire group was 91 days (range, 10-2251 days). Eleven patients were alive at a median follow-up of 1670 days (range, 67-2251 days), 1 with autologous recovery and 1 with relapsed lymphoma. The actuarial projected 3-year survival is 19%. Infection was the primary cause of death. These results suggest that unrelated umbilical cord blood transplantation is a viable option for adult patients and should be explored in patients with earlier-stage disease.

Effect of posaconazole on cytochrome P450 enzymes: a randomized, open-label, two-way crossover study

Posaconazole is an antifungal with a wide-spectrum of activity against common and emerging fungal pathogens. In this randomised, open-label, two-way crossover study, the potential for drug interactions with posaconazole via the cytochrome P450 (CYP450) enzyme pathway was evaluated. Thirteen subjects received posaconazole tablets (2 x 100 mg) once daily for 10 days or no treatment; following a 14-day washout period, subjects were crossed over to the alternate treatment. The inhibition spectra of posaconazole were examined using a cocktail of the following probe substrates: caffeine (CYP1A2), tolbutamide (CYP2C8/9), dextromethorphan (CYP2D6 and total CYP3A4), chlorzoxazone (CYP2E1), and midazolam (hepatic CYP3A4). Except for midazolam, which was intravenously infused on Day 10, the cocktail probes were administered simultaneously on Day 9 during both treatment periods. Blood and urine samples were collected at specified times to quantitate probe substrates and/or metabolites. Based on insignificant differences in mean probe ratios, posaconazole did not inhibit CYP1A2, 2C8/9, 2D6, or 2E1. However, the midazolam AUC((tf)) was higher in the posaconazole than no-treatment group (93.4 n gh/ml versus 51.4 ng h/ml, P<0.01), indicating inhibition of hepatic CYP3A4. Drug interactions mediated by various CYP450 are common with the currently available triazole antifungals, however these results suggest that posaconazole may have an improved and more narrow drug interaction profile (CYP3A4 only) compared with other triazoles.

A randomized, double-blind trial comparing pegylated interferon alfa-2b to interferon alfa-2b as initial treatment for chronic hepatitis C

This international, randomized, active-controlled, parallel-group, double-blind dose-finding study compared peginterferon alfa-2b (PegIntron) to interferon alfa-2b for the initial treatment of compensated chronic hepatitis C. We randomly assigned 1,219 subjects to receive either the standard three-times-weekly (TIW) interferon alfa-2b dose (3 MIU) or the once-weekly (QW) peginterferon alfa-2b (0.5, 1.0, or 1.5 microg/kg). Subjects were treated for 48 weeks and then followed for an additional 24 weeks. All 3 peginterferon alfa-2b doses significantly (P < or =.042) improved virologic response rates (loss of detectable serum HCV RNA) after treatment and after follow-up, as compared with interferon alfa-2b. Unlike the end-of-treatment virologic response, the sustained virologic response rate was not dose-related above 1.0 microg/kg peginterferon alfa-2b because of a higher relapse rate among patients treated with 1.5 microg/kg peginterferon alfa-2b, particularly among patients infected with genotype 1. All 3 peginterferon alfa-2b doses decreased liver inflammation to a greater extent than did interferon alfa-2b, particularly in subjects with sustained responses. No new adverse events were reported, and the majority of adverse events and changes in laboratory values were mild or moderate. In conclusion, peginterferon alfa-2b maintained (0.5 microg/kg) or surpassed (1.0, 1.5 microg/kg) the clinical efficacy of interferon alfa-2b while preserving its safety profile. The higher rate of virologic response during treatment with 1.5 microg/kg peginterferon alfa-2b in patients infected with genotype 1 and high viral levels warrants further evaluation.

Early control of HIV replication in primary HIV-1 infection treated with antiretroviral drugs and pegylated IFN alpha: results from the Primoferon A (ANRS 086) Study

IFN alpha has both antiviral and immunostimulating properties. The ANRS086 Primoferon A Study evaluated in 12 patients with primary HIV infection the tolerance and efficacy of an early and transient administration of pegylated IFN alpha, in addition to highly active antiretroviral therapy. Tolerance was good, and this regimen allowed the early control of HIV replication and rapid decay of the viral reservoir. These results support the initiation of comparative studies with pegylated INF alpha in primary HIV infection.

Chiral high-performance liquid chromatographic analysis of antifungal SCH 56592 and evaluation of its chiral inversion in animals and humans

SCH 56592 is a novel triazole antifungal agent that is active both orally and intravenously in animal models of infection. This compound is in Phase II-III clinical trials for the treatment of systemic fungal infections. SCH 56592 is a single enantiomer with four stereogenic centers; therefore, it was necessary to evaluate the possible chiral inversion of this drug candidate in animals and humans. Thus, chiral high-performance liquid chromatographic (HPLC) methods have been developed to separate SCH 56592 from its diastereomers and to evaluate its chiral inversion in rats, dogs, cynomolgus monkeys, and humans. Chiral HPLC analysis involved the use of a Chiralcel OD column set at 39 degrees C with a mobile phase of hexane-ethanol-diethylamine and a fluorescence detector set at an excitation wavelength of 270 nm and an emission wavelength of 390 nm. Plasma or serum samples were subjected to solid phase extraction on a C(2) cartridge followed by HPLC analysis. The method was sensitive with a limit of quantitation of 0.1 microg/ml in dog serum. The linearity was satisfactory, as shown by correlations of >0.997 and by visual examination of the calibration curves. The precision and accuracy were satisfactory, as indicated by coefficients of variation (CV) ranging from 1.1 to 12.1% and bias values ranging from -11.0 to 9.0%. Chiral HPLC analysis indicated that SCH 56592 was not subjected to chiral inversion in rats, dogs, cynomolgus monkeys, and humans.

Randomized cross-over trial of progenitor-cell mobilization: high-dose cyclophosphamide plus granulocyte colony-stimulating factor (G-CSF) versus granulocyte-macrophage colony-stimulating factor plus G-CSF

PURPOSE

Patient response to hematopoietic progenitor-cell mobilizing regimens seems to vary considerably, making comparison between regimens difficult. To eliminate this inter-patient variability, we designed a cross-over trial and prospectively compared the number of progenitors mobilized into blood after granulocyte-macrophage colony-stimulating factor (GM-CSF) days 1 to 12 plus granulocyte colony-stimulating factor (G-CSF) days 7 to 12 (regimen G) with the number of progenitors after cyclophosphamide plus G-CSF days 3 to 14 (regimen C) in the same patient.

PATIENTS AND METHODS

Twenty-nine patients were randomized to receive either regimen G or C first (G1 and C1, respectively) and underwent two leukaphereses. After a washout period, patients were then crossed over to the alternate regimen (C2 and G2, respectively) and underwent two additional leukaphereses. The hematopoietic progenitor-cell content of each collection was determined. In addition, toxicity and charges were tracked.

RESULTS

Regimen C (n = 50) resulted in mobilization of more CD34(+) cells (2.7-fold/kg/apheresis), erythroid burst-forming units (1.8-fold/kg/apheresis), and colony-forming units-granulocyte-macrophage (2.2-fold/kg/apheresis) compared with regimen G given to the same patients (n = 46; paired t test, P<.01 for all comparisons). Compared with regimen G, regimen C resulted in better mobilization, whether it was given first (P =.025) or second (P =.02). The ability to achieve a target collection of > or =2x10(6) CD34(+) cells/kg using two leukaphereses was 50% after G1 and 90% after C1. Three of the seven patients in whom mobilization was poor after G1 had > or =2x10(6) CD34(+) cells/kg with two leukaphereses after C2. In contrast, when regimen G was given second (G2), seven out of 10 patients failed to achieve the target CD34(+) cell dose despite adequate collections after C1. Thirty percent of the patients (nine of 29) given regimen C were admitted to the hospital because of neutropenic fever for a median duration of 4 days (range, 2 to 10 days). The higher cost of regimen C was balanced by higher CD34(+) cell yield, resulting in equivalent charges based on cost per CD34(+) cell collected.

CONCLUSION

We report the first clinical trial that used a cross-over design showing that high-dose cyclophosphamide plus G-CSF results in mobilization of more progenitors then GM-CSF plus G-CSF when tested in the same patient regardless of sequence of administration, although the regimen is associated with greater morbidity. Patients who fail to achieve adequate mobilization after regimen G can be treated with regimen C as an effective salvage regimen, whereas patients who fail regimen C are unlikely to benefit from subsequent treatment with regimen G. The cross-over design allowed detection of significant differences between regimens in a small cohort of patients and should be considered in design of future comparisons of mobilization regimens.

A phase I trial of recombinant human interleukin-1 beta (OCT-43) following high-dose chemotherapy and autologous bone marrow transplantation

We studied the effects of escalating doses of recombinant human IL-1 beta in patients receiving high-dose chemotherapy and ABMT for metastatic breast cancer or malignant melanoma. Sixteen patients received IL-1 beta, 4 to 32 ng/kg/day administered subcutaneously for 7 days beginning 3 h after bone marrow infusion. Three patients at the highest dose level also received G-CSF following completion of IL-1 beta. All patients completed the 7 days of therapy. The majority of patients experienced chills and fever following one or more injections, and seven had severe pain at the injection site. There was one episode of hypotension and one episode of transient confusion at the highest dose level; other significant toxicity was not identified. Recovery of neutrophils to > 0.5 x 10(9)l and platelet transfusion independence occurred at a median of 23 and 22 days, respectively, which was comparable to historical controls. The mean number of bone marrow colony-forming unit granulocyte-macrophage (CFU-GM) per 10(5) mononuclear cells on day +21 post-ABMT was more than twice that of control patients or patients receiving G-CSF or GM-CSF. A linear correlation was found between the dose of IL-1 beta and endogenous concentrations of several cytokines. These patients also displayed significantly higher concentrations of endogenous G-CSF compared to historical controls receiving GM-CSF. While IL-1 beta was moderately toxic and had no effect on recovery of peripheral blood counts after ABMT, the increased number of bone marrow CFU-GM suggests that the addition of G- or GM-CSF to a short course of IL-1 beta may accelerate hematologic recovery.

Placental blood as a source of hematopoietic stem cells for transplantation into unrelated recipients

BACKGROUND

Transplantation of bone marrow from unrelated donors is limited by a lack of HLA-matched donors and the risk of graft-versus-host disease (GVHD). Placental blood from sibling donors can reconstitute hematopoiesis. We report preliminary results of transplantation using partially HLA-mismatched placental blood from unrelated donors.

METHODS

Twenty-five consecutive patients, primarily children, with a variety of malignant and non-malignant conditions received placental blood from unrelated donors and were evaluated for hematologic and immunologic reconstitution and GVHD. HLA matching was performed before transplantation by serologic typing for class I HLA antigens and low-resolution molecular typing for class II HLA alleles. In donor-recipient pairs who differed by no more than one HLA antigen or allele, high-resolution class II HLA typing was done retrospectively. Fordonor-recipient pairs who were mismatched for two HLA antigens or alleles, high-resolution typing was used prospectively to select the best match for HLA-DRB1.

RESULTS

Twenty-four of the 25 donor-recipient pairs were discordant for one to three HLA antigens. In 23 of the 25 transplant recipients, the infused hematopoletic stem cells engrafted. Acute grade III GVHD occurred in 2 of the 21 patients who could be evaluated, and 2 patients had chronic GVHD. In vitro proliferative responses of T cells and B cells to plant mitogens were detected 60 days after transplantation. With a median follow-up of 12 1/2 months and a minimal follow-up of 100 days, the overall 100-day survival rate among these patients was 64 percent, and the overall event-free survival was 48 percent.

CONCLUSIONS

HLA-mismatched placental blood from unrelated donors is an alternative source of stem cells for hematopoietic reconstitution in children.

Human immunodeficiency virus type 1 Tat activity in human neuronal cells: uptake and trans-activation

Neurological dysfunction in AIDS occurs in the absence of productive infection of neurons, and may involve modulation of neuronal cell function by viral or cellular products released from surrounding infected cells. The human immunodeficiency virus type 1 (HIV-1) trans-activator protein Tat may be one such factor, as it can act as a neurotoxin, induces marked morphological changes in neurons and astrocytes in primary embryonic rodent brain cultures, and is released by certain HIV-1-infected cells. In addition, Tat can alter expression of cellular genes in several non-neuronal cell types. To explore the possibility that Tat may also mediate neuronal dysfunction in AIDS through non-lethal effects on neurons, we determined the trans-activating ability of Tat in human neuronal cells. We generated human neuronal cell lines stably expressing several HIV-1 tat genes, and also tested human neuronal cells exposed to extracellular recombinant Tat protein. Both endogenously expressed Tat as well as exogenous recombinant Tat protein up-regulated HIV-1 long terminal region (LTR)-driven gene expression by several hundred-fold. Only brief exposure to recombinant Tat was necessary and no toxic effects were seen at levels sufficient for trans-activation. Furthermore, Tat significantly enhanced virus expression in neuronal cells transfected with molecular clones of HIV-1. These results show that Tat is trans-activationally active in human neuronal cells, and can be taken up from the extracellular compartment by these cells in a biologically active form. Neurons represent an important potential target for Tat-mediated cellular dysfunction.

Inhibition of entry of HIV-1 in neural cell lines by antibodies against galactosyl ceramide

Although the CD4 molecule is the principal cellular receptor for the human immunodeficiency virus (HIV), several CD4-negative cell lines are susceptible to infection with one or more HIV strains. These findings indicate that there are alternate modes of viral entry, perhaps involving one or more receptor molecules. Antibodies against galactosyl ceramide (galactocerebroside, or GalC) inhibited viral internalization and infection in two CD4-negative cell lines derived from the nervous system: U373-MG and SK-N-MC. Furthermore, recombinant HIV surface glycoprotein gp120 bound to GalC but not to other glycolipids. These results suggest a role for GalC or a highly related molecule in HIV entry into neural cells.

NMR determination of myocardial pH in vivo: separation of tissue inorganic phosphate from blood 2,3-DPG

Phosphorus NMR can measure myocardial tissue pH from the chemical shift of inorganic phosphate (Pi) in isolated buffer-perfused hearts, but in vivo the Pi peak originating from the myocardium is obscured by the resonance of 2,3-diphosphoglycerate (DPG) in the blood, making pH difficult to determine. Taking advantage of the fact that most of the interfering DPG is within the cardiac chambers and is rapidly flowing out of the sensitive volume of our coil, we developed a pulse sequence which would separate myocardial Pi signal from interfering DPG. We tested this method on a flow phantom and in living rat heart, using exogenous glycerol phosphate as a blood-pool marker. The results indicated that signal from moving and nonmoving substances could be separated, and derived values for myocardial pH and PCr/Pi ratio were consistent with previous estimates. This method should be useful for studying myocardial acid-base physiology with NMR.

Effect of alpha-interferon therapy on bone marrow fibrosis in hairy cell leukemia

Iliac crest trephine biopsy specimens from 16 patients treated with recombinant alpha 2-interferon (alpha-IFN) for hairy cell leukemia (HCL) were examined for reticulin and collagen content. These data were compared with the hairy cell index (HCl), the proportion of hairy cells to the overall cellularity of the bone marrow. Specimens were studied immediately before alpha-IFN therapy, at 6-month intervals during, and in six patients 6 months after cessation of therapy. All patients presented with increased bone marrow fibrosis ranging from focally increased reticulin to a diffuse increase in both reticulin and collagen content. This fibrosis was observed to decrease during alpha-IFN therapy inasmuch as the hairy cell population was diminished in the bone marrow in 13 patients. Regression analysis of HCl v bone marrow fibrosis showed a positive correlation (r = .73, P less than .02). Six patients demonstrated a reduction in bone marrow reticulin and collagen to normal levels during alpha-IFN therapy. Two of six patients demonstrated increased bone marrow fibrosis and HCl 6 months after cessation of alpha-IFN therapy. Three of 16 patients exhibited no decrease in bone marrow reticulin content during therapy despite a decreased bone marrow hairy cell population.

Kinetics of creatine kinase in heart: a 31P NMR saturation- and inversion-transfer study

The kinetics of the phosphate exchange by creatine kinase (CK) was studied in solution and in the Langendorff-perfused rat heart at 37 degrees C. 31P inversion-transfer (IT) and saturation-transfer (ST) methods were applied. The kinetic parameters obtained by the two magnetization transfer methods were the same, whether in solution or in the perfused heart. Inversion transfer is the more efficient method, yielding the kinetic constants for the exchange and the relaxation rates of the transferred phosphate in both substrates, in one experiment. In solution the forward (kF) and reverse (kR) pseudo-first-order rate constants for the CK reaction (kF = k1[MgADP][H+]; kR = k-1[creatine]) as well as the concentrations of phosphocreatine (PCr), MgATP, and creatine (Cr) remained constant between pH 6.9 and pH 7.8. Equilibrium at this pH region is therefore maintained by compensating changes in the concentration of MgADP. The forward and reverse fluxes in the perfused heart were equal with an average flux ratio (fluxF/fluxR) of 0.975 +/- 0.065 obtained by both methods. Average values of kF and kR were 0.725 +/- 0.077 and 1.12 +/- 0.14 s-1, respectively. These results clearly indicate that the CK reaction in the Langendorff-perfused heart is in equilibrium and its rate is not limited by the diffusion of substrates between different locations of the enzyme. There is therefore no indication of compartmentation of substrates of the CK reaction.

Preparation of 20-(hydroxymethyl)-4-methyl-4-aza-2-oxa-5 alpha-pregnan-3-one as an inhibitor of testosterone 5 alpha-reductase

20-(Hydroxymethyl)-4-methyl-4-aza-2-oxa-5 alpha-pregnan-3-one and the corresponding 3-thione were synthesized with use of 20-(hydroxymethyl)-4-methyl-4-aza-5 alpha-pregnan-3-one as the starting material. The compounds were tested in vitro for inhibition of testosterone 5 alpha-reductase and found to be weak inhibitors with Ki's in the 10(-7) range.

Premenstrual syndrome

Premenstrual syndrome is a chronic cyclic disorder with a broad range of morbidity. The syndrome encompasses emotional, behavioral and physical symptoms, usually beginning in the week before menses and ending at the onset of menses or shortly thereafter. To date, the etiology and the most effective treatment are unknown; however, vitamin B6, progesterone and bromocriptine therapies have been advocated.

Maturation of jejunum and ileum in rats. Water and electrolyte transport during in vivo perfusion of hypertonic solutions

During osmotic diarrhea, loss of water and electrolytes appears to be greater in infants than in adults. In 2-, 3-, and 7-wk-old rats, we studied net transport of H(2)O, Na, and Cl, during in vivo perfusion of segments of the jejunum and ileum, from solutions with osmolalities of 300, 375, 500, or 700 mosmol/kg. In the jejunal segments, from the hypertonic solutions net transport of H(2)O, Na, and Cl was into the lumen and greater in the 2- than 7-wk-old rats. In the ileal segments, transport of water was into the lumen, transport of Na was minimal and variable, whereas transport of Cl was usually out the lumen. In 3-wk-old rats, transport rates were intermediate between those in 2- and 7-wk-old rats. The calculated filtration coefficient (microliters of H(2)O transported per hour per unit osmolality gradient-lumen-serum-per gram dry weight) of water suggested that the resistance to water flow did not increase with rise in luminal hypertonicity in the jejunum of the 2- and 3-wk-old rats, whereas in jejunum of the 7-wk-old rats and in ileum of rats in all three ages, the resistance to water flow increased with the rise in luminal osmolality. The differences in the transport rates and the resistance to water flow, between segments of the 2-, 3-, and 7-wk-old rats, suggested a maturational phenomenon that appears to continue beyond the 3rd wk of life and could have been due to differences in some physical property of the mucosal membrane.