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J S Miller

Publications and source records attributed to J S Miller.

At least 109 records · Page 6Linked to original sources
PubMed1996

The nucleotide sequence of RNA-1 of Indian peanut clump furovius.

The nucleotide sequence of RNA-1 of an isolate of the H serotype of Indian peanut clump virus (IPCV-H) was shown to comprise 5,841 nucleotides. The RNA contains three open reading frames (ORF) which are between nucleotides 133 and 3,522, nucleotides 3,526 and 5,103 (assuming expression by suppression of the ORF 1 termination codon) and nucleotides 5,168 and 5,539. The encoded polypeptides have M(r), of 129,687 (p130), 60,188 (p60) and 14,281 (p14). ORF 2 is thought to be expressed by suppression of the termination codon of ORF 1 to produce a M(r) 189,975 product (p190). p130 contains sequences characteristic of proteins with methyl transferase and NTP-binding properties and p190 contains these and sequences characteristic of RNA-dependent RNA polymerases. The nucleotide sequence of IPCV RNA-1 is similar to that of peanut clump virus (PCV) and corresponding encoded polypeptides are 88% (p130), 95% p60 and 75% (p14) identical. The sequences of the translation products are also similar to those of soil-borne wheat mosaic virus and barley stripe mosaic virus. Oligonucleotide primers, designed on the basis of the sequences of RNA-1 of IPCV and PCV, were effective in reverse transcription-PCR amplification of these RNAs and that of IPCV isolates of the serologically distinct L and T serotypes.

Amino Acid Sequence↗
PubMed1996

Production of human natural killer cells for adoptive immunotherapy using a computer-controlled stirred-tank bioreactor.

Large-scale ex vivo expansion of human natural killer (NK) cells for adoptive immunotherapy requires assurance of good manufacturing practices. However, maximal expansion of NK is also desired to facilitate clinical trials with large numbers of IL-2-activated NK (ANK). A closed-system stirred-tank bioreactor is amenable to computer control of culture variables, thereby reducing the risk of contamination. We demonstrate that NK cultured in 250-ml spinner flasks expand 2.5-fold more than NK cultured in stationary tissue culture wells. We further show that during 33 days of culture, it is feasible to control the pH between 7.0 and 7.2 and the dissolved oxygen concentration at 40% of air saturation via direct on-line computer control in a 750-ml stirred-tank bioreactor. On-line measurement of optical density by a laser turbidity sensor, as a measure of cell concentration, correlated well with actual cell count data. NK expansion in the 750-ml bioreactor was 7-fold greater than in stationary tissue culture controls and 3-fold greater than in spinner flask controls. Consumption rates of glucose and oxygen and the production rate of lactate were measured and will be used to develop a nutrient feeding strategy to convert the batch reactor experiment into closed-system fed-batch or continuous flow modes. Computer-controlled stirred-tank bioreactors may facilitate clinical trials with high-purity ANK populations for adoptive immunotherapy.

Cell Culture Techniques↗
PubMed1996

A radiographic comparison of neutral cervical posture with cervical flexion and extension ranges of motion.

OBJECTIVE: To radiographically assess, using a pilot study, the relationship between the neutral cervical curve and cervical segmental ranges of motion (ROM) for flexion and extension in asymptomatic subjects. DESIGN: Survey. SETTING: Chiropractic college student health center and private practice. PATIENTS: Sixteen asymptomatic adult students with no radiographic evidence of degenerative changes. INTERVENTION: No therapeutic intervention. MAIN OUTCOME MEASURES: Neutral segmental alignment and flexion and extension segmental ranges of motion for C2-C6 evaluated relative to the subjacent segment. RESULTS: Correlations between neutral posture variables (segmental tilt and global posture) and their corresponding ROMs (segmental and global) were computed. A strong correlation was found for flexion at C4 (r = -.76, p = .0006) and at C5 (r = -.84, p = .0001). Correlations were not as strong at other vertebral levels for flexion and at all levels for extension (r = .01 to r = .52). The error in prediction of motion from neutral posture is given by the standard error of the estimate (SEE). The SEE for flexion ROM ranged from 2.6 degrees at C5 to 3.9 degrees at C6, and the SEE for extension ranged from 3.8 degrees at C4 to 6.5 degrees at C2. CONCLUSION: Correlation between neutral cervical posture and flexion or extension ranges of motion was only strong at the C4 and C5 vertebral levels. Generally, there was not good predictability of ROM from neutral posture as indicated by the R2 values and the standard errors of estimate. Further investigation is needed to determine if other variables, such as angle of the facet joints, may be influential in these postural-functional relationships.

Adult↗
PubMed1996

CD3 gamma, CD3 delta, and CD3 zeta mRNA in adult human marrow hematopoietic progenitors correlates with surface CD2 and CD7 expression.

Hematopoietic stem cells from adult marrow, cord blood, or fetal liver can differentiate into myeloid and lymphoid lineages. Early steps in this differentiation process are not yet fully understood. To correlate surface antigen expression with molecular events occurring during early lymphopoietic differentiation, we examined CD3 gamma, CD3 delta, and CD3 zeta gene expression in adult human CD34+ marrow progenitors and their subsets. Purification by fluorescence-activated cell sorter (FACS) was used to obtain 1) a CD34+ Lin-DR- population known to contain primitive, uncommitted progenitors; 2) CD34+/CD7+/CD2+ and 3) CD34+/CD7+/CD2+ cells expressing receptors associated with natural killer (NK) cell or T cell lineage commitment. We demonstrate that CD34+Lin-DR- cells do not contain CD3 gamma, CD3 delta, or CD3 zeta transcripts, consistent with the primitive uncommitted nature of progenitors in this cell population. Expression of the CD34+/CD7+/CD2- phenotype correlates with the transcription of CD3 zeta but not CD3 gamma or CD3 delta, a pattern of transcription observed in mature blood NK but not T cells. Expression of both CD7 and CD2 on CD34+ cells is associated with not only CD3 zeta gene transcription but also CD3 gamma and CD3 delta, a pattern found in T cells but not mature NK cells. We have identified unique patterns of mRNA transcription in phenotypically distinct lymphoid progenitors found in the marrow. These findings raise the possibility that although primitive NK and T cell progenitors share a common differentiation pathway, divergent NK and T lineage commitment steps may occur very early in lymphopoiesis. Our findings suggest that application of in vitro marrow and thymus culture techniques may be utilized to more fully describe commitment and differentiation of early lymphoid progenitors and define the role of the microenvironment in this process.

Adult↗
PubMed1995

Optical evidence for the unification of active galactic nuclei and quasi-stellar objects.

There is a variety of optical evidence for some unification of different types of active galactic nuclei and quasi-stellar objects (QSOs). The case is very strong for the unification of at least some Seyfert galaxies, where polarization data show that the type assigned to the Seyfert galaxy must depend on viewing direction. It has been proposed that Fanaroff-Riley type 2 (FR2) radio galaxies are quasars seen in a direction from which the quasar is obscured, and there is some limited direct evidence for this picture. The broad absorption line QSOs may be normal QSOs seen from a special direction. Some of the sources observed to have high luminosities in the far infrared could be obscured QSOs and active nuclei. Mergers and interactions are likely to play an important role in nuclear activity, and active galaxies and QSOs could change their apparent types through these encounters followed by subsequent evolution.

Journal Article↗
PubMed1995

A novel single-cell proliferation assay shows that long-term culture-initiating cell (LTC-IC) maintenance over time results from the extensive proliferation of a small fraction of LTC-IC.

We have previously shown that when adult marrow CD34+/HLA-DR- cells are cultured for 5 or 8 weeks in the presence of stroma-conditioned media with interleukin-3 (IL-3) and macrophage inflammatory protein-1 alpha (MIP-1 alpha), long-term culture-initiating cells (LTC-IC) are maintained but not expanded. However, if the same cultures are evaluated after 2 weeks, we show that LTC-IC expand 5.5- +/- 0.2-fold. Because expansion of LTC-IC is likely the result of a balance between proliferation and loss of LTC-IC, we hypothesized that, although LTC-IC proliferate in these cultures, loss of a fraction of LTC-IC underlies the lack of long-term expansion. To evaluate the fate of LTC-IC (proliferation, conservation, or loss), we performed PKH-26 labeling assays and developed a single LTC-IC proliferation assay. For PKH-26 labeling assays, CD34+/HLA-DR- cells were incubated with the membrane intercallating dye, PKH-26, before culture for 14 days in stroma-noncontact cultures + IL-3 + MIP-1 alpha. Progeny was reselected by fluorescence-activated cell sorting based on their PKH-26 fluorescence intensity. These studies showed that LTC-IC proliferate because 80% of LTC-IC at week 2 had 0.5 to 1 log lower fluorescence intensity than did freshly labeled CD34+/HLA-DR- cells. To further determine the fate of LTC-IC, we also developed a single LTC-IC proliferation assay. A population of CD34+/CD33- cells, highly enriched in LTC-IC, was sorted singly in stroma-conditioned media+IL-3 + MIP-1 alpha. After 5 weeks, the content of each well was divided equally over 8 secondary stroma-containing wells and cultured for 8 weeks to determine the capacity of the single-cell progeny to initiate 1 or more secondary stromal cultures. Progeny of single-sorted cells were able to initiate up to 8 secondary long-term cultures, demonstrating that LTC-IC proliferate in stroma-conditioned media+IL-3 + MIP-1 alpha. However, more than 65% of single-sorted LTC-IC were not conserved because their progeny could no longer initiate secondary long-term cultures. This finding indicates that, although stromal factors and IL-3 + MIP-1 alpha can induce proliferation of LTC-IC, failure to conserve a large fraction of LTC-IC results in lack of long-term expansion.(ABSTRACT TRUNCATED AT 400 WORDS)

Adipose Tissue↗
PubMed1995

Intracellular bacteria in blood smears in patients with central venous catheters.

The presence of intracellular bacteria in blood smears is usually associated with overwhelming sepsis and an ominous prognosis. Recently, the hematology laboratory at our institution documented this finding in a group of mostly asymptomatic patients. We studied seven adult patients from a tertiary care university hospital in whom intracellular bacteria were found incidentally on routine manual differential cell counts of 100 white blood cells during a 12-month period. A retrospective review of the clinical and laboratory data was performed. All seven patients were immunosuppressed and had central venous catheters in place. The blood samples positive for intracellular bacteria were all catheter derived. Six patients were asymptomatic at the time of bacteria detection, but they had blood cultures that were positive for coagulase-negative Staphylococcus; five of these patients became symptomatic 1 to 14 days after bacteria detection. Bacteremia persisted in five of these six patients until the eventual removal of the catheters. The one symptomatic patient had Pseudomonas aeruginosa bacteremia and died shortly after admission. The finding of intracellular bacteria in routine differential blood cell counts from a central venous catheter blood specimen most likely indicates active infection. We recommend that central venous catheters be removed in such patients, even if the patient is asymptomatic.

Adult↗
PubMed1995

Hematopoietic growth factors for graft failure after bone marrow transplantation: a randomized trial of granulocyte-macrophage colony-stimulating factor (GM-CSF) versus sequential GM-CSF plus granulocyte-CSF.

Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte-macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM-CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G-CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM-CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1995

[Cytolytic activity by lymphokines (LAK activity) in chronic myeloid leukemia].

BACKGROUND: Recent studies indicate that patients with chronic myeloid leukemia (CML) have a population of benign cytolytic cells (natural killer or NK) in their peripheral blood which may expand and activate in vitro in the presence of interleukin-2 (IL-2) leading to cytolytic cells activated by lymphokine or LAK cells (lymphokine-activated killer). METHODS: Thirteen patients with CML in the chronic phase of a median of 8 months (range: 1-43) in length and 13 healthy individuals were studied. The NK cells were separated from the peripheral blood by centrifugation by density gradient, elutriation and depletion in flasks with the CD5 and CD8 monoclonal antibodies. The resulting cell solution was cultivated in medium with IL-2 (1,000 U/ml) for 16 days with the count, phenotypic study and cytotoxicity tests of non adherent cells (LAK) being thereafter performed. RESULTS: Following the separation, the CD56+/CD3- cells constituted 6.9 +/- 2.4% of the total of the patients with CML. At day 16 of the culture, the non adherent cells of the CD56+/CD3- phenotype (LAK cells) were found to be 57.9 +/- 4.4% of the total (expansion = 31 +/- 10.4 fold with respect to the initial number of NK cells). The LAK cells showed intense cytotoxic activity versus the killer-sensitive K562 cell lines (76.2 +/- 4.2% of lysis to the effector/target cell proportion 20:1 and 5.6 +/- 1.3% to the proportion 0.08:1) and Raji killer-resistant (65.7 +/- 4.3% and 3.8 +/- 1.6%, respectively). Thus, the grade of LAK cell expansion and their cytotoxicity in patients with CML were significantly lower than in healthy individuals. CONCLUSIONS: Chronic phase patients with chronic myeloid leukemia may generate, in vitro, a population of LAK cells with intense cytotoxic activity in the peripheral blood.

Adult↗
PubMed1995

Posttransfusion purpura following bone marrow transplantation.

BACKGROUND: Thrombocytopenia is a major cause of morbidity and hospital expense following bone marrow transplantation. Platelet transfusions in these patients are frequently complicated by the recipient's development of antibodies to HLA class I antigens. When these patients become refractory to the transfusion of HLA-matched platelets, the recipient's platelet antigen phenotype must be determined, to ensure that donor platelets will be phenotypically compatible. Cases of alloimmunization to HPA-1a and HPA-1b resulting in refractoriness to transfused platelets and the subsequent development of a posttransfusion purpura-like syndrome are reported. CASE REPORTS: In the first case, a 43-year-old woman with Stage IV infiltrating ductal breast cancer presented to the hospital for a transplant of autologous peripheral blood stem cells. After the transplant, her platelet count remained less than 10 x 10(9) per L, despite daily platelet transfusions, including HLA-matched platelets. Fourteen days following the transplant, her serum was found to contain anti-HPA-1a. Initially, the patient was refractory to the transfusion of HPA-1a-negative platelets, but after treatment with intravenous immunoglobulin, she had transient increases in posttransfusion platelet counts. She was also treated with a staphylococcal protein A immunoadsorption column and has not had any such subsequent refractoriness. Her genotype has been found, by use of allele-specific oligonucleotide hybridization with white cell DNA, to be HPA-1b/1b. The second case involved a 32-year-old woman with chronic myelogenous leukemia who received an unrelated-donor marrow transplant. Three years later, her CML recurred, and she was treated with interferon-alpha. Four months afterward, she experienced interferon-alpha-induced thrombocytopenia and the interferon therapy was discontinued. She received 12 platelet transfusions in 20 days, but none was effective. Antibodies specific for HLA antigens and HPA-1b were detected, and three HLA-matched, HPA-1b-negative apheresis platelet components were given, but without effect. Two days after treatment with methylprednisolone (1 g intravenously) and prednisone (2 mg/kg/day orally), her platelet count was 26 x 10(9) per L, and after 8 more days, it was 102 x 10(9) per L, without further transfusions. She was found to be homozygous for HPA-1a (HPA-1a/1a). CONCLUSION: Anti-HPA-1a and anti-HPA-1b can cause refractoriness to platelet transfusions in bone marrow transplant patients. Testing for platelet-specific antibodies should be considered in all patients who are refractory to HLA-matched platelets.

Adult↗
PubMed1995

Natural killer cell proliferation is dependent on human serum and markedly increased utilizing an enriched supplemented basal medium.

We studied the effects of basal medium and human serum on the ex vivo expansion of CD56+/CD3- natural killer cells (NK). We demonstrated that sorted NK cultured for 18 days with 10% human AB serum without accessory cells in a 2:1 DMEM/F12 basal medium expanded significantly greater (6.4 +/- 0.9-fold, n = 14) than when cultured in standard RPMI 1640 basal medium (3.7 +/- 0.67-fold, n = 16; p = 0.019). Supplementation of the DMEM/F12 mixture with 2-mercaptoethanol (2ME), ethanolamine, L-ascorbic acid, and sodium selenite significantly augmented NK proliferation (16.3 +/- 2.5-fold, n = 11; p < 0.001) compared with DMEM/F12 without supplements. NK growth kinetics demonstrated that both the growth rate and the duration of exponential growth were increased by medium supplements. Addition of 2ME-containing supplements to cultures of NK with accessory cells augments NK proliferation, recruits NK progenitors, and has a serum-sparing effect. For the large-scale expansion of NK, we demonstrate a greater than 30-fold increase (n = 7) in the number of activated natural killer cells (ANK) derived from CD5/CD8-depleted PBMNC when cultured for 35 days in supplemented DMEM/F12 versus RPMI 1640 basal medium (197.6 +/- 95.0-fold versus 6.3 +/- 2.1-fold, respectively). Serum-free media (AIM-V and X-VIVO 10) were unable to support NK proliferation. These data suggest that utilizing 2:1 DMEM/F12 + 2ME-containing supplements instead of standard RPMI 1640 as a basal medium can increase the proliferation of cytotoxic NK while reducing the culture interval and the amount of serum needed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Pelvic congestion syndrome: a new approach to an unusual problem.

Pelvic congestion syndrome (PCS) is an uncommon and frequently overlooked cause of debilitating pelvic pain. The well-described clinical presentation is that of pain and fullness exacerbated by prolonged standing, coitus, and in the premenstrual period in multiparus women. Physical signs include vulvar varices that can communicate with the saphenous vein in the groin, causing thigh or buttock varices. The diagnosis is usually confirmed by ovarian vein venography demonstrating reflux to the ovaries and often into the thigh with erect positioning and valsalva. Standard surgical treatment is bilateral ovarian vein ligation and excision or ligation of as many collaterals as possible. The traditional approach is bilateral retroperitoneal incisions, with medial rotation of the viscera. We report the first patient managed transperitoneally using minimally invasive techniques. Our case suggests that this approach can easily and safely be performed by surgeons experienced in laparoscopic surgery with the advantages of improved cosmesis, less postoperative pain, and rapid convalescence typical of other minimally invasive procedures. Additionally, it provides the opportunity to perform diagnostic laparoscopy as well.

Adult↗
PubMed1994

Eicosanoids mediate insect nodulation responses to bacterial infections.

We propose that nodule formation is mediated by eicosanoids in insects. Nodulation is the temporally and quantitatively predominant cellular defense response to bacterial infection in insects and other invertebrates. Inhibition of eicosanoid biosynthesis in larvae of the tobacco hornworm Manduca sexta immediately prior to intrahemocoelic infections with the bacterium Serratia marcescens strongly reduced the nodulation response. Inhibition of eicosanoid biosynthesis also reduced formation of cellular aggregates at 1 hr postinfection, which indicates that eicosanoids mediate early stages of nodulation. Separate treatments with specific inhibitors of phospholipase A2, cyclooxygenase, and lipoxygenase reduced nodulation, which supports the view that nodule formation is a complex process involving prostaglandins and lipoxygenase products. The inhibitory effects of the phospholipase A2 inhibitor dexamethasone on nodulation were apparent by 1 hr after infection, and the effects increased, relative to controls, over 24 hr. The dexamethasone effects were expressed in a dose-dependent manner, and they were reversed by treating infected insects with eicosanoid-precursor polyunsaturated fatty acids. Treatments with the saturated fatty acid 16:0, which is not an eicosanoid precursor, did not reverse the dexamethasone effects on nodulation. These findings strongly support the identification of nodulation as a specific insect cellular defense mechanism that is mediated by eicosanoids.

Animals↗
PubMed1994

CD34+/CD33- cells reselected from macrophage inflammatory protein 1 alpha+interleukin-3--supplemented "stroma-noncontact" cultures are highly enriched for long-term bone marrow culture initiating cells.

Human hematopoietic stem cells are thought to express the CD34 stem cell antigen, low numbers of HLA-DR and Thy1 antigens, but no lineage commitment antigens, CD38, or CD45RA antigens. However, fluorescence-activated cell sorted CD34+ subpopulations contain not more than 1% to 5% primitive progenitors capable of initiating and sustaining growth in long-term bone marrow culture initiating cells (LTBMC-ICs). We have recently shown that culture of fresh human marrow CD34+/HLA-DR- cells separated from a stromal layer by a microporous membrane ("stroma-noncontact" culture) results in the maintenance of 40% of LTBMC-ICs. We hypothesized that reselection of CD34+ subpopulations still present after several weeks in stroma-noncontact cultures may result in the selection of cells more highly enriched for human LTBMC-ICs. Fresh marrow CD34+/HLA-DR- cells were cultured for 2 to 3 weeks in stroma-noncontact cultures. Cultured progeny was then sorted on the basis of CD34, HLA-DR, or CD33 antigen expression, and sorted cells evaluated for the presence of LTBMC-ICs by limiting dilution analysis. We show that (1) LTBMC-ICs are four times more frequent in cultured CD34+/HLA-DR- cells (4.6% +/- 1.7%) than in cultured CD34+/HLA-DR- cells (1.3% +/- 0.4%). This suggests that HLA-DR antigen expression may depend on the activation status of primitive cells rather than their lineage commitment. We then sorted cultured cells on the basis of the myeloid commitment antigen, CD33. (2) These studies show that cultured CD34+/CD33- cells contain 4% to 8% LTBMC-ICs, whereas cultured CD34+/CD33+bright cells contain only 0.1% +/- 0.03% LTBMC-ICs. Because LTBMC-ICs are maintained significantly better in stroma-noncontact cultures supplemented with macrophage inflammatory protein 1 alpha (MIP-1 alpha) and interleukin-3 (IL-3) (Verfaillie et al, J Exp Med 179:643, 1994), we evaluated the frequency of LTBMC-ICs in CD34+/CD33- cells present in such cultures. (3) CD34+/CD33- cells present in MIP-1 alpha + IL-3-supplemented cultures contain up to 30% LTBMC-ICs. The increased frequency of LTBMC-ICs in cultured CD34+ subpopulations may be the result of terminal differentiation of less primitive progenitors, loss of cells that fail to respond to the culture conditions or recruitment of quiescent LTBMC-ICs. The capability to select progenitor populations containing up to 30% LTBMC-ICs should prove useful in studies examining the growth requirements, self-renewal, and multilineage differentiation capacity of human hematopoietic stem cells at the single-cell level.

Animals↗
PubMed1994

Myelodysplastic syndrome after autologous bone marrow transplantation: an additional late complication of curative cancer therapy.

Myelodysplastic syndrome (MDS) is a complication of conventional antineoplastic therapy but has rarely been reported after autologous bone marrow transplantation (ABMT). We reviewed records of 206 patients who underwent ABMT for lymphoma at the University of Minnesota (Minneapolis, MN) between 1974 and 1993. Of 206 patients who underwent ABMT for non-Hodgkin's lymphoma (NHL) or Hodgkin's disease (HD), 9 patients developed an MDS or secondary acute leukemia between 5 and 60 months (median 34 months) post-BMT. Two patients had relapsed after transplant and received additional therapy before the diagnosis of MDS. They were censored from the statistical analysis, resulting in a cumulative incidence of 14.5% +/- 11.6% (95% confidence interval) at 5 years. Three patients (15.2% +/- 18.0%) had HD, and four (14.0% +/- 14.7%) had NHL. In vitro BM purging had no affect on the incidence of MDS, although patients receiving peripheral blood stem cells had a projected MDS incidence of 31% +/- 33% versus 10.5% +/- 12% if BM cells were used (p = .0035). The patients had received a median of 14 cycles (range, 6 to 40) of chemotherapy before autologous transplantation; Five of nine patients received radiation therapy before BMT conditioning, and all patients received radiation before the diagnosis of MDS. No BM cytogenetic abnormalities were evident pretransplant in three of three patients studied, and all nine had normal pretransplant BM morphology. All patients had morphologic BM findings typical of MDS, and six of six studied had clonal cytogenetic abnormalities. At the diagnosis of MDS, all nine patients were without clinical, radiographic, or autopsy evidence of recurrent lymphoma; Three of the nine patients have died from complications of cytopenias at 23, 36, and 45 months after transplant (3 to 10 months after the diagnosis of MDS), whereas 6 survive 8 to 63 months after transplantation (1 to 34 months post-MDS). These data emphasize the cumulative leukemogenic potential of standard and salvage radiation and chemotherapy regimens and highlight treatment-induced MDS as an important and frequent late complication of potentially curative BM transplant therapy.

Adult↗
PubMed1994

Differentiation of natural killer (NK) cells from human primitive marrow progenitors in a stroma-based long-term culture system: identification of a CD34+7+ NK progenitor.

We have recently described a marrow stroma-dependent long-term culture system that supports differentiation of CD34+ human marrow primitive progenitors into natural killer (NK) cells. We postulate that CD7 expression may be an early event in commitment of hematopoietic progenitors to the NK lineage. Here we compare the characteristics of CD34+7- and CD34+7+ marrow cells cultivated in the stroma-based NK culture system. These CD34+ populations were further compared with a marrow derived, more committed, CD34-7+ progenitor to emphasize the continuum of NK development and to highlight differences between progenitors in our assays. No progenitor proliferated when plated in media without stroma, underscoring the importance of stroma in NK differentiation. Plating progenitor populations in interleukin-2 containing media directly on preestablished, allogeneic, irradiated marrow stroma for 5 weeks resulted in CD56+CD3- NK cells; however, characteristics of the cultured populations differed. Fold expansion and cloning efficiency of the CD34+7+ population, determined by a functional limiting dilution assay was significantly higher than of the CD34+7- or CD34+7+ populations. This suggests that the CD34+7+ population is highly enriched for an NK progenitor and a possible intermediate in NK lineage differentiation. Further dividing the CD34+7+ population by the relative fluorescence of CD7 into CD34+7+dim and CD34+7+bright populations showed that the CD34+7+bright population exhibited a significantly higher cloning frequency than parallel experiments with CD34+7+dim cells (11.8% +/- 2.4% v 2.4% +/- 0.7%, n = 6; P = .005). Plating of the more primitive CD34+7- population in a transwell system (which separates progenitors from stroma by a microporous membrane) prevents differentiation into NK cells. In contrast, plating of CD34+7+ progenitors in transwells resulted in generation of NK cells. These data suggest that primitive, but not more mature NK progenitors may require direct contact with stroma for the initial differentiation steps. Finally, differentiation of the NK progenitors in this stroma-dependent model results in expression of CD2 not present on any of the starting populations. This observation suggests that marrow stroma can stimulate CD2 expression on NK progenitors in a previously undescribed fashion that may be analogous to the thymic effect on CD2 expression in immature T lymphocytes. These observations identify early steps in the commitment of primitive marrow CD34+ hematopoietic progenitors to a lymphoid lineage and underscore the importance of coexpression of CD7 with CD34 as an early lymphoid commitment characteristic and direct progenitor-stroma interactions in this process.

Adolescent↗
PubMed1994

Expansion and activation of human natural killer cells for autologous therapy.

Ex vivo depletion of lymphocytes has been used to decrease the incidence of acute graft-versus-host disease following the allogeneic bone marrow transplantation. Many depletion techniques also remove natural killer (NK) cells that may mediate a beneficial graft-versus-leukemia effect. In this paper we review our studies on ex vivo expansion and activation of NK cells for use in the therapy of chronic myelogenous leukemia.

Bone Marrow Transplantation↗