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P J Stiff

Publications and source records attributed to P J Stiff.

At least 19 recordsLinked to original sources
PubMed2007

Ex vivo expansion of umbilical cord blood stem cells for transplantation: growing knowledge from the hematopoietic niche.

Umbilical cord blood transplantation (UCBT) in adults is limited by the small number of primitive hematopoietic stem cells (HSC) in each graft, resulting in delayed engraftment post transplant, and both short- and long-term infectious complications. Initial efforts to expand UCB progenitors ex vivo have resulted in expansion of mature rather than immature HSC, confounded by the inability to accurately and reliably measure long-term reconstituting cells. Ex vivo expansion of UCB HSC has failed to improve engraftment because of resulting defects that promote apoptosis, disrupt marrow homing and initiate cell cycling. Here we discuss the future of ex vivo expansion, which we suggest will include the isolation of immature hematopoietic progenitors on the basis of function rather than surface phenotype and will employ both cytokines and stroma to maintain and expand the stem cell niche. We suggest that ex vivo expansion could be enhanced by manipulating newly discovered signaling pathways (Notch, Wnt, bone morphogenetic protein 4 and Tie2/angiopoietin-1) and intracellular mediators (phosphatase and tensin homolog and glycogen synthase kinase-3) in a manner that promotes HSC expansion with less differentiation. Improved methods for ex vivo expansion will make UCBT available to more patients, decrease engraftment times and allow more rapid immune reconstitution post transplant.

Adult↗
PubMed2006

Retrospective utility of bronchoscopy after hematopoietic stem cell transplant.

Fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) is thought to be the procedure of choice to evaluate pulmonary infiltrates in hematopoietic stem cell transplant (HSCT) recipients. We retrospectively reviewed 91 bronchoscopies performed on 190 in-patient HSCT recipients admitted or treated for pneumonia from January 1994 to December 2004. These yielded a diagnosis 49% of the time with an overall survival of 35 days post-bronchoscopy. We were unable to detect any survival benefit from an addition to the treatment regimen after a positive result from analysis of the BAL fluid or transbronchial biopsy. The most common bacteria isolated was Pseudomonas that was often resistant to the patient's current antibiotics, suggesting that in lieu of this diagnostic procedure, changes to better cover resistant Gram-negative bacteria are reasonable. Although transbronchial biopsies provided an additional diagnosis in one out of 21 biopsies performed, six of the seven complications in our series were directly related to the transbronchial biopsy. With approximately a 50% yield from a bronchoscopy, additional treatment given after only 20% of all bronchoscopies, and no detectable survival benefit with a bronchoscopy that yielded a diagnosis, the utility of a bronchoscopy in this patient population is questioned by these data.

Adolescent↗
PubMed2006

Management of the adverse effects associated with intravenous bisphosphonates.

Intravenous bisphosphonates are widely used to treat hypercalcemia and to reduce skeletal-related morbidity among cancer patients. However, serious complications, generally occurring in less than 2% of patients participated in phase III clinical trials, including acute systemic inflammatory reaction, ocular inflammation, renal failure, nephrotic syndrome, electrolyte imbalance, and osteonecrosis of the maxilla and mandible have all been increasingly reported. Yet, strategies to deal with these complications are becoming clear. Acute systemic inflammatory reaction is often self-limited and becomes less intense during subsequent treatments. For patients who develop ocular symptoms, prompt ophthalmologic evaluation is crucial to determine the safety of a subsequent bisphosphonate therapy. Patients who receive long-term pamidronate should be evaluated at intervals for early sign of nephritic syndrome as timely cessation of the agent may result in a full recovery. To reduce the risk of severe electrolyte abnormalities, particularly hypocalcemia, correcting any pre-treatment electrolyte abnormality and supplementing vitamin D and calcium may be helpful. Finally, to reduce the risk of osteonecrosis of the maxilla and mandible, obtaining a full dental evaluation before treatment and avoidance of invasive dental procedures is suggested. The three commonly used intravenous bisphosphonates (pamidronate, zoledronic acid, and ibandronate), are generally safe; ibandronate has to date been the least reported to be associated with renal side effects. As clinical indications of intravenous bisphosphonates continue to expand, prescribing clinicians should be familiar with these possible adverse effects and discuss them with patients before commencing or continuing on therapy.

Antineoplastic Agents↗
PubMed2006

Reliability and validity of a patient self-administered daily questionnaire to assess impact of oral mucositis (OM) on pain and daily functioning in patients undergoing autologous hematopoietic stem cell transplantation (HSCT).

Oral mucositis (OM) is a frequent complication of myeloablative therapy and HSCT. We evaluated the feasibility, reliability, and validity of a new patient self-reported daily questionnaire on OM and its impact on daily functions. This OM Daily Questionnaire (OMDQ), containing 10 items, was developed for use in palifermin clinical trials. In a phase 3 study, 212 patients received palifermin or placebo for three consecutive days before conditioning and three consecutive days after HSCT. Compliance rates were consistently >80% for most patients. Mouth and throat soreness (MTS) and MTS-Activity Limitations (MTS-AL) (swallowing, drinking, eating, talking, and sleeping) scores on consecutive days were highly correlated (days 7,8 = 0.70-0.86; test-retest reliability). Correlations among items measuring the same construct ranged between 0.5 and 0.8 (internal consistency reliability). The WHO Oral Toxicity scale was the clinical comparator to assess the criterion, discriminative, and evaluative validities of MTS-related questions. Most correlation coefficients between the WHO and MTS ranged between 0.45 and 0.55. Patients with more severe WHO OM grades had higher MTS mean scores. Changes in MTS scores were similar, but patients detected changes 1-3 days earlier than clinicians. In conclusion, the OMDQ is a feasible, reliable, valid, and responsive patient-reported measure of OM severity.

Activities of Daily Living↗
PubMed2006

Patients' understanding of disease status and treatment plan at initial hematopoietic stem cell transplantation consultation.

Patients referred for hematopoietic stem cell transplantation (HSCT) often have knowledge deficits about their disease and overestimate their prognosis making it difficult initially to discuss potentially life-threatening transplant options. To determine patients' understanding of their disease and the adequacy of a 3-h consultation at our center, we developed a survey that measured perceived knowledge deficits of disease, prognosis, and emotional status before and after their initial consultation. Ninety nine consecutive eligible patients completed the survey. Although 76.7% claimed adequate information about their disease pre-HCST visit, 51.5 and 41.4% respectively lacked knowledge about their 1-year prognosis with and without any therapy. After the visit, 66.7% of the patients had obtained enough information to make an informed decision regarding HSCT versus 23.2% pre-visit, and a significant reduction in the need for further information was reported by 53.5% of patients (P<0.001). Patients were not overwhelmed or confused by the visit and there was a small but significant decrease in negative affect. Measures to increase patients understanding of their disease and its prognosis pre-HSCT consultation visit are warranted; however, a 3-h consultation visit provides the majority of patients with sufficient information to make an informed decision about the risk/benefit ratio of HSCT.

Data Collection↗
PubMed2005

Second allografts for relapsed hematologic malignancies: feasibility of using a different donor.

A second allogeneic hematopoietic stem cell transplant (HSCT) for relapsed hematologic malignancies is an option in select patients after an initial allograft has failed. If the original donor is not available, a different donor may have to be considered. We report our experience of performing a second allogeneic HSCT using a different donor in patients with relapsed leukemia and lymphoma. In a 5-year period, six patients underwent a second allograft with myeloablative conditioning using a different donor. Four of these were retransplanted using a matched-unrelated donor. Four of the patients (67%) remain progression-free at a median follow-up of 32 months (range 3-72). There were no cases of transplant-related mortality. We conclude that a second allogeneic HSCT using a different donor is a viable option for selected patients relapsing after an allograft if the original donor is not available.

Adolescent↗
PubMed2004

Analysis of remobilization success in patients undergoing autologous stem cell transplants who fail an initial mobilization: risk factors, cytokine use and cost.

Inadequate stem cell mobilization is seen in approximately 25% of patients undergoing autotransplantation for hematologic malignancies. Remobilization strategies include chemotherapy/cytokine combinations or high-dose cytokines alone or in combination. From 1/1997 to 7/2002, we remobilized 86 patients who failed an initial mobilization (median total CD34=0.72 x 10(6)/kg) in sequential cohorts using high-dose G-CSF (32 microg/kg/day) or G-CSF(10 microg/kg/day)+GM-CSF (5 microg/kg/day). No difference in CD34/kg yields were seen (G-CSF alone: 2.2 x 10(6) and G-CSF+GM-CSF 1.6 x 10(6)) in the median 3 aphereses performed (P=0.333). Of the 86, 23 (27%) failed the second mobilization; 14 were remobilized again (yield=1.5 x 10(6) CD34/kg; three aphereses). Of the 86, 93% went to transplant: three progressed, and three had inadequate stem cells. Significant risk factors for a failed remobilization were: number of stem-cell-damaging regimens (P=0.015), time between last chemotherapy and first mobilization (P=0.028), and higher WBC at initiation of first mobilization (P=0.04). High-dose G-CSF (32 microg/kg/day) was more costly @ USD $9,016, vs $5,907 for the G-CSF+GM-CSF combination (P<0.001). Most patients failing an initial mobilization benefit from a cytokine only remobilization. Lower cost G-CSF+GM-CSF is as effective as high-dose G-CSF.

Adult↗
PubMed2000

High-dose chemotherapy and autologous stem-cell transplantation for ovarian cancer: an autologous blood and marrow transplant registry report.

BACKGROUND: Autologous transplantation is increasingly used to treat epithelial ovarian cancer. However, it is not clear which patients may benefit. OBJECTIVE: To determine overall and progression-free survival and factors associated with favorable outcome after autotransplantation for ovarian cancer. DESIGN: Observational cohort study. SETTING: 57 centers reporting to the Autologous Blood and Marrow Transplant Registry (ABMTR). PATIENTS: 421 women who received transplants between 1989 and 1996. INTERVENTIONS: High-dose chemotherapy using diverse regimens with hematopoietic stem-cell rescue. MEASUREMENTS: Primary outcomes were progression-free survival and overall survival. Multivariate analyses using Cox proportional hazards regression considered the following factors: age, Karnofsky performance score, initial stage, histologic characteristics, previous therapy, remission status, extent of disease, graft source, transplant regimen, and year of transplantation. RESULTS: Most patients had extensive previous chemotherapy. Forty-one percent had platinum-resistant tumors, and 38% had tumors at least 1 cm in diameter. Only 34 patients (8%) received transplants as part of initial therapy. The probability of death within 100 days was 11% (95% CI, 8% to 14%). Two-year progression-free survival was 12% (CI, 9% to 16%), and 2-year overall survival was 35% (CI, 30% to 41%). Younger age, Karnofsky performance score of at least 90%, non-clear-cell disease, remission at transplantation, and platinum sensitivity were associated with better outcomes. Progression-free and overall survival were 22% (CI, 12% to 33%) and 55% (CI, 42% to 66%), respectively, for women with a high Karnofsky performance score and non-clear-cell, platinum-sensitive tumors. CONCLUSIONS: Some subgroups of patients with ovarian cancer seem to have good outcomes after autotransplantation, although several biases may have affected these observations. Phase III trials are needed to compare such outcomes with outcomes of conventional chemotherapy.

Age Factors↗
PubMed2000

Management of cancer treatment-related diarrhea. Issues and therapeutic strategies.

The cancer treatment-related diarrhea caused by acute graft-versus-host disease (GVHD) and chemotherapeutic agents, particularly fluoropyrimidines and irinotecan, significantly affects patient morbidity and mortality. The mechanisms causing cancer treatment-related diarrhea are not fully understood, but histopathologic evidence points to a multifactorial process that causes an absorptive and secretory imbalance in the small bowel. Cancer treatment-related diarrhea could be life-threatening, yet assessment and treatment are not currently standardized. Several clinicians participated in a closed roundtable meeting to review the mechanisms of chemotherapy-induced diarrhea (CID) and GVHD-induced diarrhea, management issues in cancer treatment-induced diarrhea, and pharmacologic approaches to treatment. The meeting produced a proposal for new treatment guidelines and an algorithm, which include the use of octreotide for the management of CID- and GVHD-induced diarrhea. The development of diarrhea assessment guidelines that expand on the current National Cancer Institute criteria and allow for better patient management was also proposed.

Antineoplastic Agents↗
PubMed2000

Status of high-dose chemotherapy for breast cancer: a review.

The purpose of this review is to analyze the current status of high-dose chemotherapy (HDCT) with autologous stem cell transplantation for patients with breast cancer. Current results from the major prospective phase 2 and phase 3 trials in metastatic breast cancer (MBC) and high-risk primary breast cancer (HRPBC) are reviewed. Prognostic factors and future research directions are also discussed. The encouraging results of phase 2 trials suggested a benefit for HDCT in HRPBC and some categories of patients with MBC. Some investigators have argued that patient selection might have been a critical factor in those studies. Recently reported randomized trials in patients with chemosensitive MBC have included only small numbers of patients in complete remission and thus have not adequately addressed the relative value of HDCT versus maintenance standard-dose chemotherapy in this patient subset. Although initial results of 2 studies have been reported, most randomized phase 3 studies of HDCT in HRPBC require longer follow-up before definitive conclusions can be made about its efficacy in this setting. We conclude that the role of HDCT for HRPBC or MBC patients has not yet been fully defined. Longer follow-up of the ongoing randomized trials is necessary, and their mature results will help clarify this important question. In the meantime, it is imperative that research continues, to enhance the efficacy of the procedure. This may come through incorporating more active drugs into HDCT regimens and combining HDCT with novel strategies aimed at eradication of posttransplantation minimal residual disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Management strategies for the hard-to-mobilize patient.

Delayed hematopoietic engraftment, particularly of platelets, is seen in 5-35% of patients undergoing high-dose chemotherapy with autologous stem cell transplantation. Studies indicate that delayed engraftment is related to low CD34+ cell dose, and that risk factors for poor mobilization of CD34+ cells relate primarily to the type and extent of prior therapy. Data indicating an appropriate strategy to ensure that 'hard-to-mobilize' patients will achieve adequate CD34+ cell numbers are limited. It is clear, however, that marrow harvesting (performed frequently by a number of centers), is of limited value. Remobilization, best accomplished with a regimen of high-dose chemotherapy and cytokines, is of benefit in selected patients, but has substantial costs and morbidity. Instead of ad hoc treatment of patients who have a poor first mobilization, high-risk groups should be identified prospectively, and strategies should be developed to ensure adequate mobilization in all high-risk patients. The first randomized trial utilizing this approach has recently been reported. In this trial, stem cell mobilization with granulocyte colony-stimulating factor (G-CSF) alone was compared to mobilization with G-CSF combined with stem cell factor (SCF) in heavily pretreated patients with Hodgkin's and non-Hodgkin's lymphoma. The combination of G-CSF and SCF led to collection of a higher total CD34+ cell dose compared to G-CSF alone. Further, more patients in the combination group were able to mobilize an optimal CD34+ cell dose (ie 5 x 10(6)/kg). Additional trials are needed to determine long-term outcomes and the economic impact of achieving optimal stem cell mobilization in these patients, who would otherwise not be candidates for high-dose chemotherapy.

Blood Cell Count↗
PubMed1999

High-dose melphalan with autotransplantation for refractory multiple myeloma: results of a Southwest Oncology Group phase II trial.

PURPOSE: To evaluate high-dose melphalan followed by autologous stem-cell transplantation in patients with refractory multiple myeloma. PATIENTS AND METHODS: Multiple myeloma patients with alkylating agent or vincristine/doxorubicin/dexamethasone-refractory disease were eligible for the phase II multi-institutional Southwest Oncology Group trial S8993. Patients up to age 70 years were enrolled between April 15, 1991, and May 1, 1996. Patients without prior stem-cell collection were primed with high-dose cyclophosphamide (HD-CTX; 6 g/m(2)) and granulocyte-macrophage colony-stimulating factor. After stem-cell procurement, patients received melphalan 200 mg/m(2) with autologous transplantation. Upon recovery from melphalan, patients were to receive interferon alfa-2b until relapse. RESULTS: Seventy-two patients were enrolled onto S8993; five were ineligible and one received no therapy. Of the 66 assessable patients, 56 patients underwent the transplant procedure; 54 were assessable for response and 56 for toxicity. The response to HD-CTX (n = 37) included three complete remissions (CRs; 8%) and five partial remissions (PR; 14%); response to melphalan (n = 54) included 16 CRs (30%) and 19 PRs (35%), for an overall CR and >/= PR (n = 66; intent-to-treat) of 27% and 58%, respectively. Toxicities included six treatment-related deaths: two during HD-CTX and four during transplantation. The median progression-free survival (PFS) and overall survival (OS) durations on an intent-to-treat basis from transplant registration was 11 months and 19 months (95% confidence interval, 14 to 29 months), respectively. The 3-year actuarial PFS and OS rates were 25% and 31%, respectively. CONCLUSION: High-dose therapy with melphalan 200 mg/m(2) is feasible with high response rates (58% overall) and an OS of 19 months in patients with refractory multiple myeloma.

Adult↗
PubMed1998

Autologous bone marrow transplantation for patients with relapsed or refractory diffuse aggressive non-Hodgkin's lymphoma: value of augmented preparative regimens--a Southwest Oncology Group trial.

PURPOSE: To determine the toxicity and prognosis of patients with relapsed and refractory diffuse aggressive non-Hodgkin's lymphoma (NHL) who underwent an autologous bone marrow transplant (ABMT) using augmented preparative regimens, treated in a major cooperative group setting, and to examine prognostic factors for outcome. PATIENTS AND METHODS: Ninety-four patients with either chemosensitive (50 patients) or chemoresistant (44 patients) relapse, including 22 who failed induction chemotherapy, were treated with high-dose cyclophosphamide and etoposide with total-body irradiation (TBI) (67 patients) or an augmented carmustine (BCNU), cyclophosphamide, and etoposide (BCV) preparative regimen (27 patients) and an ABMT at 16 Southwest Oncology Group (SWOG) transplant centers. All relapsing patients were required to undergo a minimum of two courses of salvage therapy to determine chemosensitivity before transplant. Overall (OS) and progression-free survival (PFS) were determined and a Cox regression model was used to assess potential prognostic variables. RESULTS: Of the 94 eligible patients, there were 10 (10.6%) deaths before day 50 posttransplant because of infection (six deaths), hemorrhagic alveolitis (three deaths), or bleeding (one death). The median 3-year PFS and OS for the entire group was 33% and 44%. For those with chemosensitive disease the PFS and OS were 42% and 55%, whereas for those with chemoresistant disease the PFS and OS were 22% and 29%. The PFS and OS for those failing induction chemotherapy were 27% and 32%. The relapse rates within the first 3 years for the chemosensitive relapse, chemoresistant, and induction failure groups were 61%, 40%, and 59%, respectively. For both PFS and OS, only disease status at transplant was a significant factor in the multivariate Cox model. CONCLUSION: These results single institutional pilot trials exploring augmented preparative regimens. Patients undergoing transplantation for resistant disease, particularly those failing induction chemotherapy, appear to have an improved prognosis as compared with reports using standard preparative regimens. Therapies other than manipulation of standard preparative regimens appear to be required to decrease relapses following autotransplantation.

Adult↗
PubMed1998

Blood and marrow transplantation in relapsed or refractory non-Hodgkin's lymphoma.

It was not until 1995 that a phase III randomized trial demonstrated that autologous stem cell transplants (ASCT) improve the progression-free and overall survival of patients with relapsed refractory diffuse aggressive non-Hodgkin's lymphoma. Investigators are now focusing on improving the clinical benefit of transplants. The relative contributions made by more intensive preparative regimens, purging, concomitant immunotherapy, and the timing of transplants are under study. Also, as transplant trials shift from relapsed disease to initial therapy, anticipated benefits must be balanced against both short-term and long-term toxicities.

Bone Marrow Purging↗
PubMed1997

High-dose chemotherapy with autologous transplantation for persistent/relapsed ovarian cancer: a multivariate analysis of survival for 100 consecutively treated patients.

PURPOSE: To examine the prognostic factors associated with prolonged progression-free survival (PFS) and overall survival (OS) in 100 consecutively treated women undergoing autologous stem-cell transplant for advanced ovarian cancer. PATIENTS AND METHODS: From October 1989 to February 1996, we transplanted 100 patients with ovarian cancer following chemotherapy with high-dose carboplatin, mitoxantrone, and cyclophosphamide with or without cyclosporine (n = 70); melphalan and mitoxantrone with or without paclitaxel (n = 25); or other regimens (n = 5). Their median age was 48 years (range, 23 to 65), 70% had papillary serous histology, 72% had grade III tumors, 66% were platinum-resistant, and 61% had > or = 1 cm bulk. The median number of prior regimens was two (range, one to six). Univariate and multivariate analyses were performed to examine age (< v > or = mean), stage, initial bulk, histology, grade, response to initial therapy, number of prior regimens, time from diagnosis to transplant, transplant regimen, platinum sensitivity, and bulk (< v > or = 1 cm) at transplant. RESULTS: The median PFS and OS times for the 100 patients were 7 and 13 months. A stepwise Cox proportional hazards model identified tumor bulk (P = .0001), and cisplatin sensitivity (P = .0249) as the best predictors of PFS. Age (P = .0017), bulk at transplant (P = .0175), and platinum sensitivity (P = .0330) provided the best prediction of OS. The median PFS and OS times for the 20 patients with platinum-sensitive, < or = 1-cm disease were 19 and 30 months. No differences in OS were seen when chemotherapy or surgery was used to achieve a minimal disease state. CONCLUSION: Before consideration of high-dose therapy for recurrent/persistent advanced ovarian cancer, patients should undergo debulking surgery or chemotherapy to achieve a minimal disease state. Patients with platinum-resistant, bulky disease should not be transplanted. The optimal patients for this therapy may be those with minimal disease responsive to initial chemotherapy.

Adult↗
PubMed1997

Granulocyte-macrophage colony-stimulating factor/interleukin-3 fusion protein versus granulocyte-macrophage colony-stimulating factor after autologous bone marrow transplantation for non-Hodgkin's lymphoma: results of a randomized double-blind trial.

PURPOSE: A phase III trial to compare PIXY321 with granulocyte-macrophage colony-stimulating factor (GM-CSF) following high-dose therapy and autologous bone marrow transplant (ABMT) was conducted to evaluate the time to hematopoietic recovery. PATIENTS AND METHODS: One hundred seventy-seven patients with non-Hodgkin's lymphoma (NHL) receiving ABMT were randomized to receive either PIXY321 750 micrograms/m2/d divided into two subcutaneous (SC) doses or GM-CSF 250 micrograms/m2/d as a 2-hour intravenous (IV) infusion starting on day 0 post-ABMT for a maximum of 28 days. RESULTS: The median time to reach an absolute neutrophil count (ANC) > or = 500/microL in the PIXY321 group was 17 days versus 19 days in the GM-CSF group (P = .07) and the median time to reach platelet transfusion independence in the PIXY321 group was 25 days versus 23 days in the GM-CSF group (P = .30). The toxicity profiles of the two agents appeared to be equivalent with the exception of more patients in the PIXY321 group with a rash (64%) compared with the GM-CSF group (48%) (P = .028). A logistic regression model identified the use of a non-total-body irradiation (TBI) regimen and/or receipt of unpurged marrow and a body-surface area greater than 2.0 m2 as predictive of faster neutrophil engraftment, and those three factors, as well as the receipt of < or = two prior chemotherapy regimens as predictive for rapid platelet engraftment. CONCLUSION: There was a trend toward a slight improvement in neutrophil engraftment post-ABMT with the PIXY321 administered by an SC route compared with GM-CSF administered by an IV route. However, no differences could be identified between the two agents with respect to the time to platelet transfusion independence. Patient, regimen, and graft characteristics were most predictive of the engraftment tempo.

Adolescent↗
PubMed1996

Identification of a human erythroid progenitor cell population which expresses the CD34 antigen and binds the plant lectin Ulex europaeus I.

Two and three color flow cytometry of normal human bone marrow was used to identify CD34+ progenitor cells and examine their binding to the plant lectin Ulex europaeus I (Ulex). In normal bone marrow, 48.48 +/- 17.4% of the CD34+ cells bind to Ulex. Two color flow cytometry was used to sort CD34 + cells, and subsets of CD34+ cells, CD34+ Ulex+ and CD34+ Ulex-. These populations were sorted into colony assays to assess myeloid (CFU-GM) and erythroid (BFU-E) progenitors. The CD34+ Ulex+ subset was 84 +/- 14% BFU-E colonies (mean +/- S.D.) and had the highest cloning efficiency of 28 +/- 13%. Three color analysis of CD34+ Ulex+ cells showed staining with other erythroid (CD71, GlyA) antibodies and lack of stain. ing with myeloid (CD13, CD45RA) antibodies. These studies confirmed the erythroid characteristics of this subpopulation.

Antibodies↗