Barriers to mental health service use among hematopoietic SCT survivors.

This study examined barriers to mental health service use and the demographic, medical and psychosocial correlates of these barriers among hematopoietic SCT (HSCT) survivors. A sample of 253 HSCT survivors who were 1 to 3 years posttransplant completed measures of demographic, physical, psychological and social characteristics as well as a newly modified measure of barriers to mental health service use. Only 50% of distressed HSCT survivors had received mental health services. An exploratory factor analysis of the barriers to mental health service use scale yielded four factors: scheduling barriers, knowledge barriers, emotional barriers and illness-related barriers. Patients with higher social constraints (perceived problems discussing the illness experience with significant others) reported higher levels of all four types of barriers. General distress and transplant-related posttraumatic stress symptoms were positively associated with emotional, knowledge and illness-related barriers to mental health service use, whereas physical and functional well-being were inversely associated with these barriers. Having more knowledge barriers and more emotional barriers predicted a lower likelihood of receiving mental health services, as did lower levels of education and general distress. Results suggest that a significant number of HSCT survivors may benefit from education about mental health services that is tailored to individual barriers.

The evolution of hematopoietic SCT in myelodysplastic syndrome.

Allogeneic hematopoietic SCT (allo-HCT) is the only curative therapy for myelodysplastic syndrome (MDS). Numerous myeloablative (MA), nonmyeloablative SCT (NST) and reduced conditioning transplant (RIC) studies have included MDS patients. Twenty-four MA HCT studies published from 2000 and 2008 reported OS and disease-free survival (DFS) ranging from 25 and 16% at 2 years to 52 and 50% at 4 years. In these publications, the incidence of grades II-IV acute GVHD was 18-100%, chronic GVHD 13-88%, relapse risk 24% at 1 year to 54.5% at 4 years and TRM 19% at day 100 to 61% at 5 years. From 2003 to 2008, 30 publications combining RIC and NST reported OS and DFS from 22 and 20% at 2 years to 79 and 79% at 4 years. Incidence of grades II-IV acute GVHD ranged from 9 to 63%, chronic GVHD 18 to 80%, relapse risk 6 to 61% and TRM 0% at day 100 to 34% at 5 years. The wide range in the published results leaves many unanswered questions. Although no ideal transplant conditioning has emerged, many of the MA and RIC studies used BU-based regimens and used a recipient age cutoff of 50-55 years for MA HCT. Similarly, there is no agreement on the use of induction or hypomethylating therapy before HCT, but azacitidine and decitabine are gaining increasing attention as a bridge to HCT. Until recently, the International Prognostic Scoring System (IPSS) dictated the use and timing of HCT. The WHO classification and WHO Prognostic Scoring System (WPSS) may be better suited in predicting the outcomes and should probably be incorporated in transplant algorithms. Most published MDS transplant series combine matched related donors (MRD) and matched unrelated donors (MUD). Umbilical cord blood (UCB) grafts will likely broaden the population of MDS patients eligible for allografting, but outcome data for MDS are scant. At this time, it is reasonable to consider the availability of an MRD or MUD as separate from an UCB graft in the decision of transplantation for MDS. The development of RIC, improvements in supportive therapy and alternative donor selection will provide better OS for MDS patients undergoing transplantation. Simultaneously, better understanding and medical therapy of MDS are leading us to re-examine patient selection and the timing of HCT. The results of HCT for MDS continue to improve together with the outlook of patients afflicted with myelodysplasia.

Noninvasive ratio indexes to evaluate fibrosis staging in chronic hepatitis C: role of platelet count/spleen diameter ratio index.

OBJECTIVES: Noninvasive evaluation of fibrosis is an on-going effort in the management of chronic hepatitis C. This study was planned to noninvasively evaluate fibrosis staging. DESIGN: We evaluated the biochemical, functional [aminopyrine breath test (ABT)] and ultrasonographic variables of 75 chronic hepatitis C patients. RESULTS: Clinical [body mass index (BMI)], biochemical [aspartate aminotransferase (AST), alanine aminotransferase (ALT) and platelets (PLT)] and ratio indexes, together with the ABT, showed a higher relationship with fibrosis: initial (score2) fibrosis: BMI (24+/-2 vs. 26+/-2, P=0.0007), AST (56+/-36 vs. 88+/-65, P=0.0159), ALT (92+/-54 vs. 139+/-108, P=0.0290), PLT (220+/-64 vs. 173+/-61, P=0.0007), PLT/spleen diameter ratio (PLT/SPD) (2133+/-786 vs. 1540+/-681, P=0.0003), AST/platelet count ratio index (APRI) (0.80+/-0.87 vs. 1.51+/-1.47, P=0.0010), ABT%d/h30 min (10.8+/-4.5 vs. 7.6+/-3.8, P=0.0007), ABT%d/cum120 min (8.9+/-3.3 vs. 6.5+/-3.1, P=0.0007). Considering the differences between fibrosis score 2 and 3 patients, BMI, ABT and PLT/SPD ratio proved to be statistically significant. Multivariate stepwise analysis (with and without BMI) identified two models for distinguishing between initial and evident fibrosis: Model 1: -0.569+(BMIx0.107)+(APRIx0.169)-(PLT/SPDx0.304), and Model 2: 2.376+( APRIx0.152)-(ABTd/h30x0.043)-(PLT/SPDx0.249). These models showed concordance in identifying or ruling out evident fibrosis in 76% and 78.7% of the patients respectively. The PLT/SPD ratio also showed 78.7% concordance with the histological score. CONCLUSION: These results suggest that noninvasive evaluation of fibrosis in chronic hepatitis C may be considered an effective tool thanks to the use of an inexpensive, reproducible ratio index.

Collection of autologous PBSC in patients with polycythemia vera.

BACKGROUND: Allogeneic stem-cell transplantation (SCT) can eradicate myelofibrosis (MF), but is limited by donor availability and toxicity. We previously reported normalization of counts and resolution of MF after ablative, syngeneic SCT in spent phase polycythemia vera (PV). Hence, GvL is not required to eradicate MF. Autologous SCT may advance treatment for spent phase PV by restoring effective hematopoiesis. The influence of organomegaly, myelosuppression and MF on PBSC collection has not been studied in the setting of PV. METHODS: Sixteen patients with PV underwent PBSC collection. Mobilization was with filgrastim alone, with a target cell content of 2.5 x 10(6) CD34(+)/kg. All myelosuppression was discontinued 2 weeks prior to collection. RESULTS: Median ages at diagnosis and collection were 47 and 57 years, respectively. Organomegaly, MF and use of myelosuppressive therapies were present in 10 (63%), 4 (25%) and 7 (44%) patients. Median total nucleated cells (TNC) and CD34(+) counts were 8.3 x 10(8)/kg and 4.98 x 10(8)/kg. MF had an adverse effect on TNC (p=0.05) but not on the CD34(+) content. Time from diagnosis and the use of myelosuppresion had no influence on TNC and CD34(+) contents. Four patients had CD34(+) contents <2.5 x 10(6)/kg. Complete blood count (CBC) parameters were not predictive of CD34(+) content. DISCUSSION: Autologous PBSC collection is feasible in PV several years after diagnosis. Organomegaly and MF are not absolute contraindications for collection. Discontinuing myelosuppresion for 2 weeks before mobilization appears sufficient to collect adequate numbers of CD34(+) progenitors.

Human leukocyte antigens (HLA)-Cw as prognostic indicators in autologous transplantation for lymphoma.

The human leukocyte antigens (HLA) function as transplantation antigens and as markers in disease association. Disparity at the HLA A, B, Cw, and DR loci in allogeneic stem cell transplants results in an increased incidence of graft-versus-host disease, graft rejection, and decreased survival. HLA class I loci A, B, and Cw also function as ligands for natural killer (NK) cell receptors in an interaction that predominantly inhibits cytolysis of target antigens. This HLA-NK cell inhibitory function is required for protection against auto-aggression, and is of unclear significance in other clinical settings. Furthermore, the prevention of auto-aggression is HLA molecule specific as demonstrated by the association of specific HLA types with autoimmune diseases. It is not known whether the HLA molecules might serve as markers for outcome in autologous transplants. We investigated an association of HLA class I molecules and early transplant outcome in a cohort of patients who underwent autologous transplantation for the treatment of lymphoma. In this retrospective study, HLA class I molecules were analyzed to determine whether they affect transplant outcome. HLA typing was performed by microlymphocytotoxicity assays. Factors such as age, sex, disease type, lactate dehydrogenase (LDH), cell dose, type of graft, and transfusion events were reviewed. Outcome was defined as death (or survival) at 6 months from the date of transplant. HLA-Cw8 was significantly associated with poor outcome (odds ratio = 18 and 9.3, p = 0.01 and 0.02 in homozygous and all patients, respectively). The HLA-A and B locus molecules were not associated with outcome. Age, sex, elevated LDH, and cell dose were not associated with outcome. A blood progenitor cell dose of greater than 6 x 10(8) nucleated cells/kg was favorably associated with outcome (p = 0.08). The number of transfusions received was not associated with outcome. In the multivariate analysis of HLAs and factors associated with outcome, HLA-Cw8 emerged as an independent risk factor for poor outcome (p = 0.03) following autologous transplantation in lymphoma patients. The association of HLA-Cw molecules with outcome in this study group indicates a need for further investigation of the HLA-mediated interactions that affect antitumor cytotoxicity, cytokine release, and regimen related toxicity.

Long-term follow-up after allogeneic granulocyte colony-stimulating factor--primed bone marrow transplantation.

Granulocyte colony-stimulating factor (G-CSF) priming increases the number of progenitor cells in harvested bone marrow (BM) and has been used for allogeneic transplantation. Primed bone marrow (pBM) seems to offer faster engraftment than steady-state BM, but the stability of such engraftment has been questioned. The incidence of graft-versus-host disease (GVHD) and disease relapse after pBM, compared with such incidence after BM or peripheral blood progenitor allotransplantation, has not been established. We studied the long-term outcome (median follow-up, 24 months) of sibling matched allografting with G-CSF pBM. Seventeen patients received pBM from matched sibling donors primed with G-CSF 10 microg/kg per day for 2 days before BM harvest. Conditioning consisted of total body irradiation and cyclophosphamide (CY); busulfan and CY; or total lymphoid irradiation, CY, and antithymocyte globulin. All infused grafts contained > or = 3.5 to 4 x 10(8) mononuclear cells per kilogram. Ten of 17 patients received methotrexate as part of their GVHD prophylaxis. International Bone Marrow Transplant Registry definitions for engraftment were used. Control subjects consisted of 112 consecutive patients who received allogeneic transplantation at our institution with steady-state BM; control subjects for length of hospitalization consisted of the subset of patients who underwent transplantation during 1996. Neutrophil engraftment occurred a median of 7 days earlier in primed bone marrow transplantation (pBMT) patients when compared with steady-state BMT patients; this shortened hospitalization by a median of 11 days. The peritransplant mortality rate was 18% in pBMT patients and 25% in BMT patients (not significant). The rate of GVHD of grade > II and the rate of relapse were almost identical in pBMT and BMT patients (GVHD: 18% and 19%, respectively; relapse: 14% and 13%, respectively). There were 4 transplant-related deaths within the first 100 days; 1 patient died of disease relapse on day 470. Twelve patients remained alive on days 430 through 1522 after BMT. Results showed that pBM allografts resulted in more rapid engraftment and shorter hospitalization. All patients maintained stable donor engraftment. In this cohort of patients, G-CSF pBMT resulted in rates of GVHD, disease relapse, and peritransplant mortality that were similar to those produced by conventional BMT.

An immunological syndrome featuring transverse myelitis, Evans syndrome and pulmonary infiltrates after unrelated bone marrow transplant in a patient with severe aplastic anemia.

A patient with severe aplastic anemia underwent a matched unrelated bone marrow transplant, following which he developed a complex autoimmune syndrome. This featured transverse myelitis, immune mediated Coombs positive hemolytic anemia and immune thrombocytopenia (Evans syndrome), pulmonary infiltrates, eosinophilia, muscle pains and cramps and lichenoid dermatitis all of which may represent manifestations of graft-versus-host disease as they showed response to immunosuppression. Thus, although immune-mediated cytopenias after an allogeneic bone marrow transplant are rare, they should be considered as a possible cause of cytopenia in post-transplant patients.

Predictive value of left ventricular ejection fraction in stem cell transplantation.

We evaluated predictive value of left ventricular ejection fraction at rest (REF) and its increment with exercise (deltaEF) on autologous and allogeneic stem cell transplantation mortality. In a 7 year period, a total of 163 patients evaluated for stem cell transplantation were studied. All were followed for at least 3 months after the transplant. REF was discriminatory for peritransplant mortality only in younger (<43 years) patients (n = 66), particularly those who underwent autologous transplantation (n = 30). Resting ejection fraction was not a discriminator for early death in any other subgroup. Cardiac reserve (deltaEF) was significantly lower in patients (n = 35), who died early. The finding was most prominent in younger patients who underwent autologous transplantation (n = 26). Combination of decreased REF and low deltaEF (n = 18) was associated with high peritransplant mortality (56%), after both autologous and allogeneic transplantation. A low REF with an appropriate deltaEF (n = 43) was associated with a 19% peritransplant mortality and no deaths in the autologous group. These observations indicate that resting ejection fraction is of only limited value for pretransplant evaluation. However, measurement of cardiac reserve during exercise can provide important prognostic information before stem cell transplantation.

Allogeneic bone marrow transplantation for advanced Waldenstrom's macroglobulinemia.

Waldenstrom's disease is a lymphoproliferative disorder that is typically treated with plasmapheresis and/or alkylating agents. In young patients, other lymphoproliferative disorders have been treated with allogeneic transplantation. Two patients with aggressive Waldenstrom's disease, who progressed in spite of multi-agent chemotherapy and autologous stem cell transplantation, in one case, underwent allogeneic transplantation from their HLA-identical donors. Both remain alive with event-free survivals of more than 3, and more than 9 years, respectively. Allogeneic transplantation should be considered for young patients with Waldenstrom's disease.

Comparative analysis of HLA-B 8101 by serology, isoelectric focusing, and sequence-based typing.

We describe a bone marrow donor evaluation on a twenty-four-year-old patient from Honduras, Central America. The patient's phenotype included a HLA-B7v, with serologic reactivity to HLA- B7, 8101, and 48, and was consistent with, HLA-B*8101. One-dimensional isoelectric focusing (IEF) identified HLA-B 7.1, a low frequency isotype that has previously been associated with the HLA-B7 variant, B*0705. To further classify this allele, sequence based typing (SBT) was performed, confirming HLA-B*8101 sequence homology. The diagnostic evaluation of this case illustrates the correlation of sequenced based typing and isoelectric focusing in defining HLA Class I antigen characteristics and the use of IEF in screening for rare and novel alleles.

Retroviral gene transfer into cord blood stem/progenitor cells using purified vector stocks.

Cord blood (CB) progenitor/stem cells (P/SC) are ideal targets for early gene therapy in individuals prenatally diagnosed with genetic disorders. Most retroviral transduction protocols were developed using adult peripheral blood stem cells (PBSC) and bone marrow (BM). Less is known about retroviral transduction of CB P/SC. We examined how timing, multiplicity of infection (MOI), and polycations in the transduction media affect transduction efficiency. Rates of transduction were determined in recently isolated CD34+ enriched CB cells and in colonies derived after various times in liquid cultures (LC). CB mononuclear cells (MNC) were separated by ficoll-hypaque centrifugation and enriched for CD34+ cells. Purity was assessed by flow cytometry. Transduction were performed with clinical-grade retroviral stocks at MOIs of 1-20. Transduction was performed with fetal bovine serum (FBS) or autologous plasma, IL-3, GM-CSF, IL-6, and SCF. The retroviral vector contained LacZ and neomycin resistance (neo) reporter genes. Transduction was determined by X-gal stain and by PCR amplification of the reporter genes. No drug selection was used. Twenty-five experiments were done. CB volumes ranged from 35-150 ml. MNC and CD34+ cell counts ranges were: 0.14-840 x 10(6) and 0.1-4.2 x 10(6), respectively. Transduction efficiency in liquid cultures ranged from 4-63%. Higher rates were seen using MOI > or = 10, 2 microg/ml polybrene, and 10% autologous CB plasma. In colonies, transduction rates were 63 to 72% by PCR and 32% by X-gal staining. In LTC-IC derived colonies, transduction was 7% by PCR. Short incubations of CD34+ CB cells with purified retroviral stocks, polybrene, and autologous sera result in high transduction rates of committed progenitors and moderately low efficiencies of transduction of LTC-IC in the absence of drug selection.

Interphase FISH analysis of sex-mismatched BMT utilizing dual color XY probes.

Interphase FISH analysis, utilizing dual color XY probes, was performed on 27 patients following allogeneic sex-mismatched bone marrow transplantation and on 31 controls. Of the 123 167 examined interphase nuclei, 63 318 were from 19 of the 21 patients (54 specimens) who engrafted, 31 827 from five of the six patients (29 specimens) who relapsed (four) or failed to engraft (one) and 24 703 from the 31 control specimens. In patients who engrafted, the mean percentage of host cells was 0.26% between day 29 and 5 years following BMT. Microchimerism of 0.7% or less than 1-5 years following BMT was not predictive of relapse. Interphase FISH analysis predicted relapse or failure of engraftment in five of the six evaluable patients. In three of five patients both conventional cytogenetics and interphase FISH of bone marrow cells provided important information regarding engraftment status and degree of chimerism.

Uptake of long chain free fatty acids is selectively up-regulated in adipocytes of Zucker rats with genetic obesity and non-insulin-dependent diabetes mellitus.

To examine whether fatty acid transport is abnormal in obesity, the kinetics of [3H]oleate uptake by hepatocytes, cardiac myocytes, and adipocytes from adult male Wistar (+/+), Zucker lean (fa/+) and fatty (fa/fa), and Zucker diabetic fatty (ZDF) rats were studied. A tissue-specific increase in oleate uptake was found in fa/fa and ZDF adipocytes, in which the Vmax was increased 9-fold (p < 0.005) and 13-fold (p < 0.001), respectively. This increase greatly exceeded the 2-fold increase in the surface area of adipocytes from obese animals, and did not result from trans-stimulation secondary to increased lipolysis. Adipocyte tumor necrosis factor-alpha mRNA levels, assayed by Northern hybridization, increased in the order +/+ < fa/fa < ZDF. Oleate uptake was also studied in adipocytes from 20-24-day-old male +/+, fa/+, and fa/fa weanlings. These animals were not obese, and had equivalent plasma fatty acid and glucose levels. Tumor necrosis factor-alpha mRNA levels in +/+ and fa/fa cells also were similar. Nevertheless, Vmax was increased 2.9-fold (p < 0.005) in fa/fa compared +/+ cells. These studies indicate 1) that regulation of fatty acid uptake is tissue-specific and 2) that up-regulation of adipocyte fatty acid uptake is an early event in Zucker fa/fa rats. These findings are independent of the role of any particular fatty acid transporter. Adipocyte mRNA levels of three putative transporters, mitochondrial aspartate aminotransferase, fatty acid translocase, and fatty acid transporting protein (FATP) were also determined; mitochondrial aspartate aminotransferase and FATP mRNAs correlated strongly with fatty acid uptake.

A murine model for human cord blood transplantation: near-term fetal and neonatal peripheral blood cells can achieve long-term bone marrow engraftment in sublethally irradiated adult recipients.

The purposes of the research reported here were first to explore a murine model for human placental and umbilical cord blood transplantation and second to evaluate the engraftment ability of ex vivo cultured hematopoietic cells. Murine near-term fetal and neonatal peripheral blood (FNPB) cells, genetically marked with the human multiple drug resistance transgene (MDR1) were used for syngeneic transplants into sublethally irradiated adult mice. Donor cells were transplanted either fresh and untreated, or after ex vivo culture in the presence of the hematopoietic growth factors recombinant murine stem cell factor, recombinant human interleukin-3 (rHu IL-3), and rHu IL-6, in a liquid culture system. To evaluate, count, and characterize FNPB progenitor cell-derived colonies, neonatal mouse mononuclear cells were cultured directly in methylcellulose with growth factors. To assess their ex vivo expansion ability, FNPB mononuclear cells were first cultured in liquid medium for 3 to 8 days and then transferred to semisolid assay plates. Evaluation of the cell counts after liquid culture showed a 1.4- to 11.6-fold increase, and the numbers of colonies observed in methylcellulose were similar to those produced by fresh FNPB cells. Donor-type engraftment was demonstrated by polymerase chain reaction (PCR) amplification of the human MDR1 transgene in the peripheral blood of all surviving animals (5 of 7 recipients of the fresh, and 3 of 8 recipients of the ex vivo-cultured cells) 2 to 4 months after transplantation. The proportion of donor leukocytes in the peripheral blood of the recipients (chimerism) was evaluated using fluorescence in situ hybridization (FISH) analysis 4 to 6 months after transplantation and ranged from 2% to 26%. In addition, bone marrow cultures were obtained from two recipient animals: one had received fresh-untreated cells and was evaluated 8 months after transplant, the other had received ex vivo cultured cells and was tested 14 months after grafting. The derived hematopoietic colonies were tested by PCR and the transgene was detected, conclusively proving long-term engraftment of donor cells. These results indicate that FNPB transplants can be successfully performed in sublethally irradiated mice with and without ex vivo culture. Long-term donor-type engraftment with sustained chimerism has been demonstrated. Thus, murine neonatal blood grafts can be used as an animal model for cord blood transplantation for gene therapy studies where complete myeloablation is not desirable and partial replacement of defective marrow may be sufficient. Furthermore, the possibility of numerically expanding hematopoietic progenitor cells contained in neonatal blood without affecting their engraftment ability could facilitate use of cord blood grafts in adult recipients.

A pilot study of allogeneic bone marrow transplantation using related donors stimulated with G-CSF.

Growth factor administration to donors prior to bone marrow (BM) harvesting results in an enrichment of the graft for myeloid precursors. In animals, growth factor-primed BM has a higher repopulating ability than untreated BM. Ten patients received an HLA-identical sibling, allogeneic transplant using granulocyte colony-stimulating factor (G-CSF)-stimulated BM. Stimulation consisted of G-CSF at 10 microg/kg/day for 2 days prior to harvest. Patients were transplanted for various benign and malignant hematological conditions. The GVHD prophylaxis consisted of cyclosporine, methotrexate and/or prednisone. Compared to untreated historical control BM, stimulated BM infusions contained similar number of nucleated cells (mean +/- s.d.: 3.5 +/- 1.5 vs 4.0 +/- 0.9 x 10(8)/kg), CD34+ cells (mean +/- s.d.: 7.5 +/- 3.0 vs 9.4 +/- 6.7 x 10(6)/kg), and CD3+ cells (mean +/- s.d.: 129 +/- 30 vs 190 +/- 59 x 10(6)/kg) but higher numbers of granulocyte-macrophage colony-forming units (mean +/- s.d.: 20 +/- 12 vs 96 +/- 34 x 10(4)/kg). Patients receiving stimulated BM had prompt and stable engraftment of white cells and platelets. On average they attained an ANC of > or = 1 x 10(9)/l 9 days earlier and a platelet count of > or = 20 x 10(9)/l 6 days earlier than historical controls receiving unstimulated HLA-identical sibling BM. Hospitalization was shortened by a mean of 10 days and transfusion requirements were modest. None of the patients developed severe GVHD or disease relapse. Two patients died of severe VOD post-BMT and thus were unevaluable for platelet engraftment. A third patient died of TTP on day 76 post-BMT. Seven patients are alive and well 49-585 days post-BMT. Stimulated BM may provide a valuable alternative to allogeneic BM and PBSC transplants. Ideal stimulation regimens need to be investigated.

Temporal association between the use of methotrexate and development of leukemia in 2 patients with rheumatoid arthritis.

To date only a single case of leukemia coincident with the use of methotrexate (MTX) in rheumatoid arthritis (RA) has been reported. We report 2 additional patients with RA, each of whom developed leukemia after receiving short term low dose MTX. Whether these cases represent an adverse effect of MTX treatment has yet to be determined.

3T3 fibroblasts transfected with a cDNA for mitochondrial aspartate aminotransferase express plasma membrane fatty acid-binding protein and saturable fatty acid uptake.

To explore the relationship between mitochondrial aspartate aminotransferase (mAspAT; EC 2.6.1.1) and plasma membrane fatty acid-binding protein (FABPpm) and their role in cellular fatty acid uptake, 3T3 fibroblasts were cotransfected with plasmid pMAAT2, containing a full-length mAspAT cDNA downstream of a Zn(2+)-inducible metallothionein promoter, and pFR400, which conveys methotrexate resistance. Transfectants were selected in methotrexate, cloned, and exposed to increasing methotrexate concentrations to induce gene amplification. Stably transfected clones were characterized by Southern blotting; those with highest copy numbers of pFR400 alone (pFR400) or pFR400 and pMAAT2 (pFR400/pMAAT2) were expanded for further study. [3H]Oleate uptake was measured in medium containing 500 microM bovine serum albumin and 125-1000 microM total oleate (unbound oleate, 18-420 nM) and consisted of saturable and nonsaturable components. pFR400/pMAAT2 cells exhibited no increase in the rate constant for nonsaturable oleate uptake or in the uptake rate of [14C]octanoate under any conditions. By contrast, Vmax (fmol/sec per 50,000 cells) of the saturable oleate uptake component increased 3.5-fold in pFR400/pMAAT2 cells compared to pFR400, with a further 3.2-fold increase in the presence of Zn2+. Zn2+ had no effect in pFR400 controls (P > 0.5). The overall increase in Vmax between pFR400 and pFR400/pMAAT2 in the presence of Zn2+ was 10.4-fold (P < 0.01) and was highly correlated (r = 0.99) with expression of FABPpm in plasma membranes as determined by Western blotting. Neither untransfected 3T3 nor pFR400 cells expressed cell surface FABPpm detectable by immunofluorescence. By contrast, plasma membrane immunofluorescence was detected in pFR400/pMAAT2 cells, especially if cultured in 100 microM Zn2+. The data support the dual hypotheses that mAspAT and FABPpm are identical and mediate saturable long-chain free fatty acid uptake.

Effect of recombinant erythropoietin on anemia and orthostatic hypotension in primary autonomic failure.

Anemia is a common complication of autonomic failure and reduced red blood cell mass may contribute to the orthostatic hypotension of these patients. We investigated whether treatment with recombinant erythropoietin improves anemia and increases blood pressure in patients with primary autonomic failure. Three patients with multiple system atrophy and autonomic failure and one with pure autonomic failure were studied. All patients had normocytic normochromic anemia and low (n = 2) or normal (n = 2) serum levels of erythropoietin. Treatment with erythropoietin, 4000 U subcutaneously biweekly for 6 weeks, increased hematocrit and blood pressure in all patients. Hematocrit increased from 33.9 +/- 0.7 to 44.3 +/- 1.4%, blood pressure in supine position increased from 150 +/- 8/87 +/- 8 (systolic/diastolic; mean +/- SD) to 166 +/- 25/92 +/- 12 mmHg, and after 3 min in the head-up tilt position from 86 +/- 21/47 +/- 15 to 102 +/- 23/63 +/- 12 mmHg, (p < 0.05). All patients reported improvement in orthostatic symptoms and increased tolerance to standing. The study shows that treatment with erythropoietin improves anemia, increases blood pressure and ameliorates orthostatic hypotension in patients with primary autonomic failure.

Mitochondrial aspartate aminotransferase expressed on the surface of 3T3-L1 adipocytes mediates saturable fatty acid uptake.

Physicochemical studies have suggested that the 43-kDa plasma membrane fatty acid binding protein (FABPpm) is closely related to the mitochondrial isoform of aspartate aminotransferase (mAspAT). In the present studies, mAspAT was not detected immunohistochemically or by immunoblotting in plasma membranes of proliferating 3T3-L1 fibroblasts. During controlled differentiation to an adipocyte phenotype, mAspAT became detectable by the second day of confluent growth, prior to accumulation of visible lipid droplets, and was strongly expressed in 8-day differentiated 3T3-L1 adipocytes. The pattern of expression paralleled the previously reported expression both of FABPpm and of the Vmax for saturable uptake of long chain free fatty acids. As with anti-FABPpm, antibodies to mAspAT selectively inhibited the uptake of [3H]-oleate in 3T3-L1 adipocytes but not in fibroblasts, while having no effect on uptake of either 2-deoxyglucose or the medium chain fatty acid octanoate. Preabsorption of anti-FABPpm with mAspAT, or of anti-mAspAT with FABPpm, abolished immunopositivity in immunohistochemical and immunoblotting studies, as well as the ability of either antibody to inhibit [3H]-oleate uptake. These studies provide strong biologic evidence for the identity of FABPpm and mAspAT, and for the hypothesis that FABPpm/mAspAT mediates the uptake of long chain free fatty acids.