Early lymphocyte recovery predicts longer survival after autologous peripheral blood stem cell transplantation in multiple myeloma

Absolute Lymphocyte Count and Outcomes of Multiple Myeloma Patients Treated with Idecabtagene Vicleucel: The US Myeloma Immunotherapy Consortium Real- World Experience

Idecabtagene vicleucel (ide-cel) has shown impressive efficacy in relapsed/refractory multiple myeloma (RRMM). This study aimed to investigate the impact of absolute lymphocyte count (ALC) on the survival outcomes of RRMM patients treated with standard of care (SOC) ide-cel. Data were collected retrospectively from 11 institutions in the U.S. Impact of ALC parameters including pre-apheresis (pre-A), pre-lymphodepletion (pre-LD), absolute and percent difference from pre-A to pre-LD on clinical outcomes after ide-cel were examined using survival analysis. A new ALC profile was created based on univariate analysis that comprises 3 groups: normal (≥1 × 109/L) pre-LD ALC (LDN), low (<1 × 109/L) pre-LD ALC (LDL) + percent reduction <37.5 (%RL), and LDL ALC + percent reduction ≥37.5 (%RH). A total of 214 SOC ide-cel recipients were included in this analysis. The median patient age was 64 years (interquartile range [IQR], 57 to 69 years), median number of prior therapies was 6 (IQR, 5 to 9), and median duration of follow-up was 5.4 months (IQR, 2.1 to 8.3 months). Most patients had both low pre-A ALC (75.3%) and pre-LD ALC (77.2%), and the reduction from pre-A to pre-LD (median, .65 to .55 × 109/L) was statistically significant. Univariate analysis showed that the LDL + %RH group had significantly worse progression-free survival (PFS) and overall survival (OS) compared to the LDL + %RL and LDN ALC groups (6-month PFS: 40% versus 67.6% and 60.9%; 6-month OS: 69.5% versus 87% and 94.3%). In multivariable analysis, after adjusting for age, performance status, cytogenetic risk, use of bridging therapy, and extramedullary disease, PFS did not maintain its statistical significance; however, OS remained significantly worse for LDL + %RH group compared to the LDN ALC group (hazard ratio [HR], 4.3; 95% confidence interval [CI], 1.1 to 17), but the difference between the LDL + %RH versus %RL groups was not statistically significant (HR, 1.7; 95% CI, .8 to 4.0). Our findings indicate that low pre-LD ALC with high %R from pre-A to pre-LD was associated with inferior survival outcomes, particularly OS, in patients who received SOC ide-cel.

The Impact of Infused Autograft Absolute Numbers of Immune Effector Cells on Survival Post-Autologous Stem Cell Transplantation

Autologous stem cell transplantation treatment has been viewed as a therapeutic modality to enable the infusion of higher doses of chemotherapy to eradicate tumor cells. Nevertheless, recent reports have shown that, in addition to stem cells, infusion of autograft immune effector cells produces an autologous graft-versus-tumor effect, similar to the graft-versus-tumor effect observed in allogeneic-stem cell transplantation, but without the clinical complications of graft-versus-host disease. In this review, I assess the impact on clinical outcomes following infusions of autograft-antigen presenting cells, autograft innate and adaptive immune effector cells, and autograft immunosuppressive cells during autologous stem cell transplantation. This article is intended to provide a platform to change the current paradigmatic view of autologous stem cell transplantation, from a high-dose chemotherapy-based treatment to an adoptive immunotherapeutic intervention.

Prognostic impact of natural killer cell recovery on minimal residual disease after autologous stem cell transplantation in multiple myeloma

INTRODUCTION

Natural killer cells are a potent effector lymphocyte subset that can induce cytotoxicity without the need for antigen sensitization or presentation. NK cells are a tempting target -for immune therapy, monoclonal antibody, or genetic engineering-to enhance immune surveillance mechanisms against myeloma cells.

MATERIALS AND METHODS

We hypothesized an association between natural killer cell recovery after autologous stem cell transplantation (ASCT) and disease outcomes in multiple myeloma patients. We concluded a prospective study that started enrolling patients in January 2020 to identify the association between absolute NK cell count two to three after ASCT and disease outcomes after autologous stem cell transplantation in multiple myeloma using univariate and multivariate analysis.

RESULTS

Natural killer cell recovery was evaluated during the third month after ASCT, day +60 to +90 post-ASCT. Our patients had a mean NK cell count of 90.53, ranging from 14 to 282 Cell/μL (Std Dev 84.64 Cell/μL). The odds of having a minimal residual disease (MRD-positivity) among patients with partial remission before transplantation is four times higher than patients with very good partial response or better (95% confidence interval 0.45-35.79). Our patients were classified into two groups based on MRD status after ASCT, an MRD-negative group of eight participants and an MRD-positive group of seven participants. The mean absolute NK cell count was significantly higher in the MRD-negative cohort, 131.38 Cell/μL, versus 43.86 Cell/μL in the MRD-positive group (p = 0.049).

CONCLUSION

We conclude that for multiple myeloma patients treated with ASCT, high absolute NK cell counts two to three months after ASCT is an independent predictor for MRD negativity.

Novel Cell and Immune Engagers in Optimizing Tumor- Specific Immunity Post-Autologous Transplantation in Multiple Myeloma

Autologous stem cell transplantation (ASCT) is an important component of treatment of multiple myeloma (MM). The post-ASCT setting offers a unique opportunity to increase myeloma specific immunity through enhancement of T and NK cell responses. The vast array of therapeutics being developed for MM, including cell-based therapies, dendritic vaccines, bispecific antibodies, and IL-15 agonists, provide the opportunity to increase tumor-specific immunity. Maintenance therapies, including immunomodulatory drugs, proteasome inhibitors, and daratumumab, exhibit a significant anti-myeloma response by modulating the immune system. Lenalidomide promotes an antitumoral immune microenvironment, whereas daratumumab can potentially cause NK cell fratricide. Thus, understanding the effects of commonly used maintenance drugs on the immune system is important. In this review, we look at current and emerging therapeutics and their integration post-ASCT in the context of immune reconstitution to improve clinical responses in patients with MM. © 2021 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

The association of mobilising regimen on immune reconstitution and survival in myeloma patients treated with bortezomib, cyclophosphamide and dexamethasone induction followed by a melphalan autograft

G-CSF only mobilisation has been shown to enhance immune reconstitution early post-transplant, but its impact on survival remains uncertain. We undertook a retrospective review of 12 transplant centres to examine overall survival (OS) and time to next treatment (TTNT) following melphalan autograft according to mobilisation method (G-CSF only vs. G-CSF and cyclophosphamide [CY]) in myeloma patients uniformly treated with bortezomib, cyclophosphamide and dexamethasone induction. Six centres had a policy to use G-CSF alone and six to use G-CSF + CY. Patients failing G-CSF only mobilisation were excluded. 601 patients were included: 328: G-CSF + CY, 273: G-CSF only. Mobilisation arms were comparable in terms of age, Revised International Staging System (R-ISS) groups and post-transplant maintenance therapy. G-CSF + CY mobilisation generated higher median CD34 + yields (8.6 vs. 5.5 × 10⁶/kg, p < 0.001). G-CSF only mobilisation was associated with a significantly higher lymphocyte count at day 15 post-infusion (p < 0.001). G-CSF only mobilisation was associated with significantly improved OS (aHR = 0.60, 95%CI 0.39-0.92, p = 0.018) and TTNT (aHR = 0.77, 95%CI 0.60-0.97, p = 0.027), when adjusting for R-ISS, disease-response pre-transplant, age and post-transplant maintenance therapy. This survival benefit may reflect selection bias in excluding patients with unsuccessful G-CSF only mobilisation or may be due to enhanced autograft immune cell content and improved early immune reconstitution.

Clinical significance of the lymphocyte-to-monocyte ratio in multiple myeloma patients with negative minimal residual disease: a single-center retrospective analysis

Minimal residual disease (MRD) is a surrogate marker for survival in multiple myeloma (MM), while the lymphocyte-to-monocyte ratio (LMR) is a prognostic factor associated with the patients' immunological status. We retrospectively evaluated the clinical impact of MRD negativity and LMR. MRD was analyzed by multicolor flowcytometry (threshold, 1 × 10-5). Fifty-eight patients (median age 70 years) who achieved complete response were included in this study. Twenty-two patients received autologous stem cell transplantation, 14 received daratumumab-based chemotherapy, and 22 received another treatment. Forty-one (70.7%) patients achieved MRD negativity. Over the median follow-up time of 15.1 months, PFS in MRD-negative patients was significantly longer than in MRD-positive patients (P = 0.020). In addition, a high LMR at MRD assessment was associated with MRD negativity (P = 0.019) and long PFS (P = 0.009). Finally, neither MRD negativity nor high LMR at MRD assessment was associated with significantly shorter PFS compared with MRD positivity or low LMR (P = 0.002). In conclusion, high LMR was associated with MRD negativity and can be used as a predictor of long PFS. Change of treatment strategy might be essential for patients with MRD positivity and high LMR at MRD assessment due to their short PFS.

Predictive Role of Immune Profiling for Survival of Multiple Myeloma Patients

Despite new efficacy drugs and cell therapy have been used for multiple myeloma (MM) patients, some patients will relapse over time. We wonder the immune system play a vital role as well as MM cell during the development of disease. It is clear that the characteristic of myeloma cell is associated with the survival of MM patients. However, the link between the immune profiling and the prognosis of the disease is still not entirely clear. As more study focus on the role of immunity on multiple myeloma pathogenesis. There are plenty of study about the predictive role of immunity on the survival of multiple myeloma patients. Up to mow, the majority reviews published have focused on the immunotherapy and immune pathogenesis. It is indispensable to overlook the predictive role of immunity on multiple myeloma patients. Here, we give a review of vital previous works and recent progress related to the predictive role of immune profiling on multiple myeloma, such as absolute lymphocyte count, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, lymphocytes and cytokines.

Autograft cellular composition and outcome in myeloma patients: Results of the prospective multicenter GOA study

BACKGROUND

Autologous stem cell transplantation (auto-SCT) is a widely used treatment option in multiple myeloma (MM) patients. The optimal graft cellular composition is not known.

STUDY DESIGN AND METHODS

Autograft cellular composition was analyzed after freezing by flow cytometry in 127 MM patients participating in a prospective multicenter study. The impact of graft cellular composition on hematologic recovery and outcome after auto-SCT was evaluated.

RESULTS

A higher graft CD34⁺ cell content predicted faster platelet recovery after auto-SCT in both the short and long term. In patients with standard-risk cytogenetics, a higher graft CD34⁺ count (>2.5 × 10⁶ /kg) was linked with shorter progression-free survival (PFS; 28 vs. 46 months, p = 0.04), but there was no difference in overall survival (OS) (p = 0.53). In a multivariate model, a higher graft CD34⁺ CD133⁺ CD38^- (>0.065 × 10⁶ /kg, p = 0.009) and NK cell count (>2.5 × 10⁶ /kg, p = 0.026), lenalidomide maintenance and standard-risk cytogenetics predicted better PFS. In contrast, a higher CD34⁺ count (>2.5 × 10⁶ /kg, p = 0.015) predicted worse PFS. A very low CD3⁺ cell count (≤20 × 10⁶ /kg, p = 0.001) in the infused graft and high-risk cytogenetics remained predictive of worse OS.

CONCLUSIONS

Autograft cellular composition may impact outcome in MM patients after auto-SCT. More studies are needed to define optimal graft composition.

Oral calcitriol in hematopoietic recovery and survival after autologous stem cell transplantation: a randomized clinical trial

BACKGROUND

Calcitriol, the active metabolite of vitamin D, is an essential regulator in the hematopoiesis and immunity. However, knowledge revealing its influence on the immune and hematologic reconstitution after hematopoietic stem cell transplantation (HSCT) in clinical trials is very limited.

OBJECTIVES

The effects of calcitriol on short-term and long-term hematopoietic recovery, relapse-free survival (RFS) and overall survival (OS) in multiple myeloma, Hodgkin's and non-Hodgkin's lymphoma following autologous peripheral blood HSCT were assessed.

METHODS

Eighty patients (age: 18-68 years) in complete remission were allocated 1:1 to two groups by balanced block randomization. Calcitriol 0.25 μg or placebo capsule was administered three times daily from transplantation to day 30. Absolute neutrophil count (ANC), absolute lymphocyte count (ALC), and platelet count (PC) were determined daily from transplantation to day 30. White blood cell count (WBC), PC, and hemoglobin concentration (HC) of days 180 and 365 were extracted from clinic files. A thorough examination for oral mucositis (OM) was completed daily during hospital stay. Adverse drug reactions (ADRs) as well as two-year RFS and OS were evaluated.

RESULTS

Median time to ANC engraftment (≥0.5 × 103/μl: 10.0 vs. 11.0 days; P = 0.98) and PC engraftment (≥20.0 × 103/μl: both 14.0 days; P = 0.58) was similar between groups. However, the median time to ALC recovery was significantly shorter in the calcitriol group (≥0.5 × 103/μl: 13.0 vs. 20.0 days; P < 0.001). Moreover, ALC recovery rates on day 15 (≥0.5 × 103/μl: 82.1% vs. 42.5%; P < 0.001) and on day 30 (≥1.0 × 103/μl: 91.7% vs. 57.5%; P = 0.001) was significantly higher with calcitriol. WBC, PC, and HC on days 180 and 365 were not significantly different between groups. None of the OM indices were modulated by calcitriol. All the ADRs were non-serious and mild, possibly or unlikely related to the intervention. In a median of 29 months follow-up, RFS was significantly better in the calcitriol group (77.0%, SE = 7.0% vs. 59.0%, SE = 8.0%; P = 0.03), albeit the OS was not affected (87.0%, SE = 5.0% vs. 92.0%, SE = 4.0%; P = 0.72).

CONCLUSION

Calcitriol could improve ALC recovery and RFS as a safe option post-HSCT. Graphical abstract Oral calcitriol 0.25 µg three times daily from transplantation to day 30 improved lymphocytes recovery and two-year relapse-free survival as a safe option in 80 patients of autologous hematopoietic stem cell transplantation in comparison with placebo.

Combined immune score of lymphocyte to monocyte ratio and immunoglobulin levels predicts treatment-free survival of multiple myeloma patients after autologous stem cell transplant

Outcomes after ASCT are highly variable making it difficult to predict risk of disease progression. We analyzed the impact of clinically available immune-related biomarkers on treatment-free survival (TFS) in 130 patients receiving Mel200 and ASCT. Absolute lymphocyte count (ALC), monocyte count (AMC), neutrophil count (ANC), and immunoglobulin (Ig) levels were collected on day -2 and 90 of ASCT. The lymphocyte-monocyte (LMR) and neutrophil-lymphocyte ratios (NLR) were then derived. At Day +90, we found that low ALC (18 versus 23 months, p = 0.04) or AMC (13 versus 25 months, p = 0.02) predicted for worse TFS. A low LMR predicted for worse TFS (16 versus 52 months, p = 0.004). Patients with two or three suppressed Ig levels had worse TFS (17 versus 51 months, p = 0.04). Median TFS for poor (low LMR and 2-3 suppressed Ig), intermediate, and good (high LMR and 0-1 suppressed Ig) risk groups was 7.5 versus 27 versus 79 months, respectively (p = 0.0004). In a multivariate analysis, a low LMR and suppressed Ig levels were strong independent predictors of poor TFS. We propose an immune score combining these available tests to stratify patients at risk for early progression and identify those who may benefit from intensified post-ASCT consolidation or immunotherapy based approaches.

Impaired lymphocyte reconstitution after autologous transplant is associated with apoptosis of CD8+ T cells and adverse clinical outcome

We noticed that the lymphocyte counts, after autologous hematopoietic stem cell transplantation, oscillated during the first 4 post-transplant months. Thereafter, the lymphocyte counts stabilized and segregated the patients into two groups, those who normalized their lymphocyte counts and those with prolonged lymphopenia. In both groups, the CD4 counts remained low for at least 6 months. However, in approximately half of the patient, the CD8 counts increased to normal or above normal values. Patients with prolonged lymphopenia had higher rates of lymphocytes' spontaneous apoptosis and the lymphocytes in patients who restored their counts expressed the intracellular CD14-derived MO2 epitope that protects the cells from apoptosis. These findings were translated to longer disease-free survival and overall survival in patients who restored the CD8 counts. Collectively, our data show that post-transplant lymphocytes that express intracellular CD14-MO2 epitope have survival advantage.

Peripheral Blood Lymphocyte-to-Monocyte Ratio as a Useful Prognostic Factor in Newly Diagnosed Multiple Myeloma

The survival of individuals with tumors may be predicted by the peripheral blood lymphocyte-to-monocyte ratio (LMR) upon diagnosis in recent studies. For patients with multiple myeloma (MM) in the era of novel agents, the prognostic significance of LMR remains unclear. In this study, the prognostic impact of LMR is evaluated by 285 patients with MM who are treated with proteasome inhibitor and/or immunomodulatory drug. LMR is a proven predictor of survival using the receiver operating characteristic curve, with 4.2 as the cutoff point. Patients with LMR ≤ 4.2 at diagnosis had poorer overall survival (OS) and progression-free survival (PFS) than those with LMR > 4.2. In addition, multivariate analysis showed that LMR less than 4.2 is an independent predictor for the OS (hazard ratio [HR]: 1.703; 95% confidence interval [CI]: 1.020–2.842; P = 0.042) and PFS (HR: 1.831; 95% CI: 1.098–3.053; P = 0.021). According to the test, the LMR at diagnosis, which functions as a simple index reflecting host systemic immunity, can predict clinical outcomes in patients with MM who are treated with new agents.

Autograft immune effector cells and survival in autologous peripheral blood hematopoietic stem cell transplantation

In addition to stem cells, T-cells, natural killer cells, dendritic cells, and monocytes are also collected and infused from the autograft in patients undergoing autologous peripheral blood hematopoietic stem cell transplantation. Recent reports have shown that these autograft immune effector cells can affect the clinical outcome postautologous peripheral blood hematopoietic stem cell transplantation. In this article, I will review the clinical impact on the survival of these autograft immune effector cells conferring the concept of autologous graft versus tumor effect.

Immune Reconstitution Following Autologous Stem Cell Transplantation in Patients with High-Risk Neuroblastoma at the Time of Immunotherapy

Outcomes for patients with high-risk neuroblastoma (HR-NBL) are significantly improved with the addition of immunotherapy (dinutuximab + cytokines) following autologous hematopoietic stem cell transplantation (auto-HSCT). We hypothesized that the immune system is not fully reconstituted at the initiation of immunotherapy. To test this hypothesis, we evaluated hematologic and immune subsets in 34 patients with HR-NBL before and after auto-HSCT. We found that absolute T, B, and NK cell counts at the time of immunotherapy were below normal in 80% of patients. Patients with residual disease at the time of transplantation had significantly lower absolute lymphocyte counts (ALC; P = .008), lower CD16⁺ cell counts (P = .009), and an abnormal ratio of cytokine-releasing to cytotoxic NK cells at the time of dinutuximab treatment. In addition, the preparative regimen used for auto-HSCT predicted immune recovery. Finally, higher total white blood cell count (P = .013) and ALC (P = .013) at 3 months after completion of therapy were measured in patients who remained in remission compared with those who relapsed. Our results indicate that most patients with HR-NBL do not have full immune reconstitution at the time of dinutuximab treatment after auto-HSCT, and that immune recovery may correlate with disease-related outcomes in patients with high-risk disease.

Infusion of autograft natural killer cell/CD14+HLA-DRDIM cell ratio predicts survival in lymphoma post autologous stem cell transplantation

The infusion of autograft absolute lymphocyte count (A-ALC) and autograft natural killer cells (A-NKC) are prognostic factors for overall survival (OS) and PFS in non-Hodgkin's lymphoma (NHL) patients undergoing autologous peripheral blood hematopoietic stem cell transplantation (APBHSCT). The human monocytic CD14⁺HLA-DR^DIM cells are associated with worse prognosis in NHL. Thus, we investigated whether the autograft A-NKC/A-CD14⁺HLA-DR^DIM ratio predicts survival in NHL. In a total of 111 NHL patients, we analyzed apheresis collection samples for the content of A-NKC and A-CD14⁺HLA-DR^DIM. With a median follow-up of 57.2 months (range: 2.1-84.6 months), patients with an A-NKC/A-CD14⁺HLA-DR^DIM ratio of ⩾0.29 experienced superior OS (5-year OS rates of 84% (95% confidence interval (CI), 72-91%) vs 48% (95% CI, 34-62%), P<0.0002, respectively) and PFS (5-year PFS rates of 59% (95% CI, 47-71%) vs 32% (95% CI, 20-48%), P<0.002, respectively). Multivariate analysis revealed that A-NKC/A-CD14⁺HLA-DR^DIM ratio was an independent predictor for PFS (hazard ratio (HR)=0.56, 95% CI, 0.32-0.96, P<0.03) and OS (HR=0.34, 95% CI, 0.16-0.68, P<0.002). The A-NKC/A-CD14⁺HLA-DR^DIM ratio provides a platform to target specific autograft immune effector cells to improve clinical outcomes in NHL patients undergoing APBHSCT.

Recovery of polyclonal immunoglobulins one year after autologous stem cell transplantation as a long-term predictor marker of progression and survival in multiple myeloma

Immunoparesis or suppression of polyclonal immunoglobulins is a very common condition in newly diagnosed myeloma patients. However, the recovery of polyclonal immunoglobulins in the setting of immune reconstitution after autologous stem cell transplantation and its effect on outcome has not yet been explored. We conducted this study in a cohort of 295 patients who had undergone autologous transplantation. In order to explore the potential role of immunoglubulin recovery as a dynamic predictor of progression or survival after transplantation, conditional probabilities of progression-free survival and overall survival were estimated according to immunoglobulin recovery at different time points using a landmark approach. One year after transplant, when B-cell reconstitution is expected to be completed, among 169 patients alive and progression free, 88 patients (52%) showed immunoglobulin recovery and 81 (48%) did not. Interestingly, the group with immunoglobulin recovery had a significantly longer median progression-free survival than the group with persistent immunoparesis (median 60.4 vs. 27.9 months, respectively; Hazard Ratio: 0.45, 95%Confidence Interval: 0.31-0.66; P<0.001), and improved overall survival (11.3 vs. 7.3 years; Hazard Ratio: 0.45, 95%Confidence Interval: 0.27-0.74; P=0.002). Furthermore, the percentage of normal plasma cells detected by flow cytometry in the bone marrow assessed at day 100 after transplantation was associated with the immunoglobulin recovery at that time and may predict immunoglobulin recovery in the subsequent months: nine months and one year. In conclusion, the recovery of polyclonal immunoglobulins one year after autologous transplantation in myeloma patients is an independent long-term predictor marker for progression and survival.

Autologous Graft-versus-Tumor Effect: Reality or Fiction?

In contrast to allogeneic hematopoietic stem cell transplantation, the current dogma is not an evidence of graft-versus-tumor effect in autologous hematopoietic stem cell transplantation; thus, it is assumed that autologous hematopoietic stem cell transplantation only relies on the high-dose chemotherapy to improve clinical outcomes. However, recent studies argue in favor of the existence of an autologous graft-versus-tumor without the detrimental complications of graft-versus-host disease due to the nonspecific immune response from the infused donor alloreactive immune effector cells in allogeneic hematopoietic stem cell transplantation. Herein, this paper reviews the clinical evidence of an autologous graft-versus-tumor effect based on the autograft collected and infused host immune effector cells and host immunity recovery after autologous hematopoietic stem cell transplantation affecting clinical outcomes in cancer patients.

Mobilization with cyclophosphamide reduces the number of lymphocyte subpopulations in the leukapheresis product and delays their reconstitution after autologous hematopoietic stem cell transplantation in patients with multiple myeloma

BACKGROUND

Autologous hematopoietic stem cell transplantation is considered the standard of care for younger patients with multiple myeloma. Several mobilization regimens are currently used, most commonly growth factors alone or in combination with chemotherapy. The aim of our study was to investigate the differences in lymphocyte subpopulation counts between three different mobilization regimens on collection day, in the leukapheresis product and on day 15 after autologous hematopoietic stem cell transplantation.

PATIENTS AND METHODS

In total 48 patients were prospectively enrolled in three different mobilization regimens; (i) filgrastim (20), (ii) pegfilgrastim (19) and (iii) cyclophosphamide + filgrastim (9). Lymphocytes, CD16+/56+ natural killer and CD4+/CD25^high T regulatory cells were determined by flow cytometry.

RESULTS

We found a statistically significant difference between the mobilization regimens. Cyclophosphamide reduced lymphocyte and natural killer (NK) cell counts on collection day (lymphocytes 1.08 × 10⁹/L; NK cells 0.07 × 10⁹/L) compared to filgrastim (lymphocytes 3.08 × 10⁹/L; NK cells 0.52 × 10⁹/L) and pegfilgrastim (lymphocytes 3 × 10⁹/L; NK cells 0.42 × 10⁹/L). As a consequence lymphocyte and NK cell counts were also lower in the leukapheresis products following cyclophosphamide mobilization regimen (lymphocytes 50.1 × 10⁹/L; NK cells 4.18 × 10⁹/L) compared to filgrastim (lymphocytes 112 × 10⁹/L; NK cells 17.5 × 10⁹/L) and pegfilgrastim (lymphocytes 112 × 10⁹/L; NK cells 14.3 × 10⁹/L). In all mobilization regimens T regulatory cells increased 2-fold on collection day, regarding the base line value before mobilization. There was no difference in T regulatory cell counts between the regimens.

CONCLUSIONS

Mobilization with cyclophophamide reduces the number of mobilized and collected lymphocytes and NK cells as compared to mobilization with growth factors only and results in their delayed reconstitution following autologous hematopoietic stem cell transplantation. We found no difference between filgrastim and pegfilgrastim mobilization.

Blood graft cellular composition and posttransplant outcomes in myeloma patients mobilized with or without low-dose cyclophosphamide: a randomized comparison

BACKGROUND

Autologous stem cell transplantation is a standard treatment in multiple myeloma (MM). Blood grafts are usually collected after mobilization with granulocyte-colony-stimulating factor (G-CSF) alone or in a combination with cyclophosphamide (CY). There is limited knowledge of the possible effects of different mobilization regimens on blood graft characteristics and posttransplant outcomes.

STUDY DESIGN AND METHODS

Thirty-eight patients with MM were included in this study. The patients were randomly assigned at registration to mobilization with either low-dose CY plus G-CSF (Arm A) or G-CSF alone (Arm B) and received three cycles of lenalidomide, bortetzomib, and dexamethasone induction. Flow cytometry analysis of lymphocyte subsets in the blood grafts after cryopreservation was performed. Hematologic and immune recovery were evaluated up to 12 months posttransplant.

RESULTS

The blood grafts in Arm A contained significantly more CD34+ cells but in Arm B there was a greater proportion of CD34+CD38- cells and higher numbers of T and B lymphocytes as well as natural killer (NK) cells. The engraftment was comparable but lymphocyte count at 15 days posttransplant was higher in Arm B (0.8 × 10(9) /L vs. 0.5 × 10(9) /L, p = 0.033). At 3 and 6 months posttransplant the total number of NK cells was also higher in G-CSF-mobilized patients. There was no difference in progression-free survival between the study arms.

CONCLUSION

CY plus G-GSF yields more CD34+ cells but seems to diminish lymphocyte and NK cell counts in the grafts and hampers immune recovery after transplantation. Thus G-CSF alone might be a preferred mobilization method due to more rapid immune recovery posttransplant.

Absolute lymphocyte count at day 29 of treatment is a powerful predictor of outcome in multiple myeloma

BACKGROUND

Survival outcomes for patients who receive treatment for newly diagnosed multiple myeloma (MM) are highly variable.

PATIENTS AND METHODS

We conducted a retrospective analysis of 38 unselected MM patients who received treatment with cyclophosphamide, thalidomide, and dexamethasone to evaluate the prognostic value of the absolute lymphocyte count at diagnosis and at the end of the initial cycle of treatment defined as day 29, termed ALC-29. The median follow-up was 54 months (range, 2-83 months).

RESULTS

We found that ALC-29, as a continuous variable, was a predictor of overall survival (OS) in MM patients (hazard ratio, 0.208; 95% confidence interval, 0.093-0.689; P = .007). Patients with an ALC-29 ≥ 0.8 × 10(9)/L (n = 16) experienced a superior median OS compared with patients with an ALC-29 < 0.8 × 10(9)/L (n = 22) with a median OS of 58.3 months versus 42.5 months respectively (P = .006). Multivariate analysis confirmed that ALC-29 ≥ 0.8 × 10(9)/L was an independent prognostic indicator of OS in our cohort of MM patients.

CONCLUSION

We concluded that the ALC-29 is a useful and simple predictor of outcome in newly diagnosed MM patients who receive standard chemotherapy. Our results support the hypothesis that host immunity plays an important role in tumor control in MM.

Infused autograft lymphocyte to monocyte ratio and survival in diffuse large B cell lymphoma

Infused autograft absolute lymphocyte count is a prognostic factor for survival after autologous peripheral hematopoietic stem cell transplantation (APHSCT) for diffuse large B cell lymphoma (DLBCL). CD14(+) HLA-DR(low/neg) immunosuppressive monocytes affect tumor growth by suppressing host antitumor immunity. Thus, we set out to investigate if the infused autograft lymphocyte to monocyte ratio (A-LMR), as a biomarker of host immunity (ie, lymphocytes) and immunosuppression (ie, monocytes), affects survival after APHSCT. From 1994 to 2012, 379 DLBCL patients who underwent APHSCT were studied. The 379 patients were randomly divided into a training set (n = 253) and a validation set (n = 126). Receiver operating characteristic and area under the curve identified an A-LMR ≥1 as the best cut-off value, which was validated by the k-fold cross-validation in the training set. Multivariate analysis showed A-LMR to be an independent prognostic factor for survival in the training set. Patients with an A-LMR ≥ 1.0 experienced superior overall survival (OS) compared with patients with an A-LMR <1.0 (median OS: 167.2 versus 17.6 months; 5-year OS: 73% [95% confidence interval (CI), 63% to 80%] versus 30% [95% CI, 2% to 38%], P < .0001, respectively) in the training set. In the validation set, an A-LMR ≥ 1 showed a median OS of 181.2 months versus 19.5 months for an A-LMR <1, and 5-year OS rates of 67% (95% CI, 52% to 79%) versus 35% (95% CI, 25% to 47%), P < .0001, respectively. The A-LMR provides a platform to engineer immunocompetent autograft to improve clinical outcomes in DLBCL patients undergoing APHSCT.

Lymphocyte subset recovery and outcome after autologous hematopoietic stem cell transplantation for plasma cell myeloma

Rapid immune reconstitution--particularly of natural killer cells (NK cells)--after allogeneic hematopoietic stem cell transplantation (HSCT) is associated with protection from relapse. Whether such an association also exists after autologous stem cell transplantation is less clear. We retrospectively assessed lymphocyte subsets after autologous HSCT in 114 patients and correlated lymphocyte recovery with outcome. CD8 T cell and NK cell counts recovered rapidly to pretransplantation levels, whereas B cell and CD4 T cell recovery were delayed. Compared with patients with low NK cells (<100/uL), high NK cell count at 1 month after HSCT was associated with significantly prolonged progression-free survival: for NK cells 100 to 200/uL hazard ratio [HR], .33 (95% confidence interval [CI]; .16 to .80; P = .004); for NK cells > 200/μL HR, .27 (95% CI, .13 to .58; P = .001). No significant protective effects were associated with rapid recovery of any other lymphocyte subset. None influenced overall survival (OS) or time to next treatment. Early NK cell recovery is associated with better progression-free survival after autologous HSCT. The failure to detect an effect on OS might be due to the salvage strategies available to these patients.

Prognostic significance of absolute lymphocyte count/absolute monocyte count ratio at diagnosis in patients with multiple myeloma

Background

Absolute lymphocyte count (ALC) in peripheral blood has recently been reported to be an independent prognostic factor in multiple myeloma (MM). Previous studies indicated that the absolute monocyte count (AMC) in peripheral blood reflects the state of the tumor microenvironment in lymphomas. Neither the utility of the AMC nor its relationship with ALC has been studied in MM.

Methods

The prognostic value of ALC, AMC, and the ALC/AMC ratio at the time of diagnosis was retrospectively examined in 189 patients with MM.

Results

On univariate analysis, low ALC (<1,400 cells/µL), high AMC (≥490 cells/µL), and low ALC/AMC ratio (<2.9) were correlated with worse overall survival (OS) (p=.002, p=.038, and p=.001, respectively). On multivariate analysis, the ALC/AMC ratio was an independent prognostic factor (p=.047), whereas ALC and AMC were no longer statistical significant. Low ALC, high AMC, and low ALC/AMC ratio were associated with poor prognostic factors such as high International Staging System stage, plasmablastic morphology, hypoalbuminemia, and high β2-microglobulin.

Conclusions

Univariate analysis demonstrated that changes in ALC, AMC, and the ALC/AMC ratio are associated with patient survival in MM. Multivariate analysis showed that, of these factors, the ALC/AMC ratio was an independent prognostic factor for OS.

Remobilization of hematopoietic stem cells with high-dose methotrexate and cytarabine in patients with non-Hodgkin's lymphoma and multiple myeloma after failure to mobilize with chemotherapy and cytokines

BACKGROUND

High-dose chemotherapy supported by autologous stem cell transplantation is an effective treatment for patients with relapsed or refractory non-Hodgkin's lymphomas (NHLs) and fit patients with multiple myeloma (MM). However, failure rates of hematopoietic stem cell mobilization are estimated to be between 5 and 30%, respectively. Thus, we investigated the efficacy of the combination chemotherapy of high-dose methotrexate (MTX) and cytarabine with granulocyte-colony-stimulating factor (G-CSF) as a remobilization method in those who failed a prior mobilization and collection with chemotherapy and G-CSF.

STUDY DESIGN AND METHODS

Mobilization failure was defined as a collection of fewer than 5 × 10(6) CD34+ cells after three to five apheresis procedures. MTX (3500 mg/m(2) in a 120-min infusion) on Day 1 and cytarabine (3000 mg/m(2) infusion for 120 min) on Day 4 and Day 5 were followed by G-CSF (10 μg/kg daily).

RESULTS

A total of eight patients (six NHL and two MM; median age, 55 years) who had failed in prior mobilization with conventional chemotherapy and G-CSF underwent the second mobilization as described in the method. Successful collection of CD34+ cells (> 5 × 10(6) /kg) was achieved in six patients (75%) with three to five apheresis procedures. The total yield of CD34+ cells/kg body weight was 6.28 × 10(6) /kg (median; range, 1.53 × 10(6) -10.09 × 10(6) /kg).

CONCLUSIONS

This preliminary result warrants further investigation of high-dose MTX and cytarabine plus G-CSF as a means to remobilize stem cells in those with prior failure to mobilize stem cells with chemotherapy and G-CSF.

Cellular immunotherapy for plasma cell myeloma

Allogeneic hematopoietic cell transplantation for plasma cell myeloma can lead to graft-vs-myeloma immunity and long-term survivorship, but limited efficacy and associated toxicities have prevented its widespread use. Cellular immunotherapies seek to induce more specific, reliable and potent antimyeloma immune responses with less treatment-related risk than is possible with allogeneic transplantation. Strategies under development include infusion of vaccine-primed and ex vivo expanded/costimulated autologous T cells after high-dose melphalan, genetic engineering of autologous T cells with receptors for myeloma-specific epitopes, administration of DC/plasma cell fusions and administration expanded marrow-infiltrating lymphocytes. In addition, novel immunomodulatory drugs such as inhibitors of the programmed death-1 T cell regulatory pathway may synergize with cellular immunotherapies.

The role of natural killer cells in immunity against multiple myeloma

Multiple myeloma (MM) is an essentially incurable malignancy associated with profound immune dysregulation. Despite the advent of novel therapies and improvements in survival over the last 10 years, death from progressive disease and infection remains a common outcome. Natural killer (NK) cells are CD56(+)CD3(-) large granular lymphocytes that constitute a key cellular subset of the innate immune system. For over 30 years, the relationship between NK cells and MM has been described in the clinical setting and characterized in the laboratory. Data suggest that NK cells may play a role in the immune response to MM; however, this effect is lost due to immunoevasive strategies utilized by MM. Nevertheless, progress in the understanding of the mechanisms perpetuating this effect have led to new opportunities to recover or augment NK cell function therapeutically in MM. In fact, the novel agents thalidomide, lenalidomide and bortezomib all confer anti-MM effects, in part, through enhancement of NK cell function. Currently, the development of therapies designed specifically to increase NK cell cytotoxicity against MM is under way. The present review summarizes the current understanding of the NK cell versus MM effect and characterizes therapeutic interventions that exert anti-MM efficacy via NK cell function against the disease.

Mobilisation strategies for normal and malignant cells

This review evaluates the latest information on the mobilisation of haemopoietic stem cells for transplantation, with the focus on what is the current best practice and how new understanding of the bone marrow stem cell niche provides new insights into optimising mobilisation regimens. The review then looks at the mobilisation of mesenchymal stromal cells, immune cells as well as malignant cells and what clinical implications there are.

Novel mobilization strategies to enhance autologous immune effector cells in multiple myeloma

The immune system plays a critical role determining the outcomes in transplanted multiple myeloma patients, since enhanced lymphocyte recovery results in improved survival. Since mobilization regimens influence the cellular subsets collected and infused for transplant, these regimens may determine immune recovery following transplant. We hypothesized that a mobilized stem cell product harboring an increased number of lymphocytes would enhance immune recovery following autologous stem cell infusion, increase lymphocyte recovery, and improve clinical outcomes. We designed a phase I immune mobilization trial using IL-2 and growth factors to increase the number of lymphocytes within the stem cell product. This regimen efficiently mobilized CD34+ progenitor cells (median: 3.6 x 10(6) cells/kg; range 1.9-6.6 x 10(6) cells/kg) and improved the immune properties of the mobilized stem cells, including an increase in CD8+ T cells expressing an NK activating receptor called NKG2D (P less than 0.004), cells that are extremely potent at killing myeloma cells using non-MHC-I restricted and TCR-independent mechanisms. Novel mobilization techniques can improve the mobilized graft and may improve clinical outcomes in myeloma patients.

Long-term impact of prior rituximab therapy and early lymphocyte recovery on auto-SCT outcome for diffuse large B-cell lymphoma

Early lymphocyte recovery following auto-SCT for non-Hodgkin's lymphoma (NHL) has been reported to be associated with improved outcome. The significance of early lymphocyte recovery following a stem cell transplant in NHL subtype diffuse large B-cell lymphoma (DLBCL) in the rituximab era remains unclear. Patients who underwent an auto-SCT at our institution for DLBCL during the time period 1998-2008 (n=115) were included in the study. Patient characteristics were well-balanced in both rituximab naïve and rituximab-exposed groups. Prior rituximab therapy did not affect lymphocyte recovery on day 14 or day 28. Lymphocyte recovery on day 14 and day 28 and prior rituximab had no impact on survival after auto-SCT for DLBCL, despite early benefit. Other factors such as age, stage at presentation, number of salvage regimens, mobilization procedure, conditioning regimen, pre-transplant radiation therapy and pre-transplant disease status had no impact on survival. Our data showed that the survival benefit with early lymphocyte recovery and prior rituximab seen in previous reports may be lost with longer follow-up. Prior rituximab therapy does not appear to influence the lymphocyte count at days 14 and 28 following auto-SCT. Our findings suggest that future trials should consider manipulating the immune system as a post transplant intervention to improve long-term outcome.

Clinical impact of absolute lymphocyte count on day 30 after unmanipulated haploidentical blood and marrow transplantation for pediatric patients with hematological malignancies

Currently, limited information is available regarding the effects of early lymphocyte recovery on transplant outcomes in pediatric patients with hematological malignancies after unmanipulated haploidentical transplantation. In this study, we evaluated the association of Day 30 absolute lymphocyte count (ALC-30) with transplant outcomes in 60 consecutive pediatric patients with hematological malignancies receiving T-cell-repleted transplantation from an haploidentical related donors. After median follow-up of 36 months (range, 1.4-75 months), higher relapse rate was observed in patients with an ALC-30 < 300 cells/μL compared to patients with an ALC-30 ≥ 300 cells/μL (35.5% vs. 13.8%, P = 0.049). More patients died of infections in those with an ALC-30 < 300 cells/μL compared with patients with an ALC-30 ≥ 300 cells/μL (25.8% vs. 3.4%, P = 0.015). The ALC-30 above the cutoff value 300 cells/μL was associated with improved overall-survival (HR 0.301, 95% CI 0.117-0.771; P = 0.012), leukemia free survival (HR 0.195, 95% CI 0.078-0.498; P=0.002), less relapse (HR 0.224 95% CI 0.070-0.717; P = 0.012), and less transplant- related mortality (HR=0.166; 95%CI 0.037-0.750; P = 0.020). Our results suggest that a higher ALC-30 ≥ 300 cells/μL) could be a useful and simple tool to predict pediatric patients with a superior outcome after unmanipulated haploidentical transplantation.

Autograft mediated adoptive immunotherapy of cancer in the context of autologous stem cell transplantation

The infused stem cell autograft in autologous stem cell transplantation (ASCT) has been viewed mainly as hematologic rescue from the myelosuppressive side effect of conditioning regimens. However, recent reports have shown that the immune effector cells collected at the same time as the stem cells can produce an autologous graft-versus-tumor effect, similar to the graft-versus-tumor effect seen in allogeneic stem cell transplantation without the detrimental effects of graft-versus-host disease. In this article, we review the different immune effector cells collected and infused from the stem cell autograft and their association with clinical outcome post-ASCT, suggesting that ASCT can be viewed not only as a therapeutic maneuver to recover bone marrow function after deliver high-dose chemotherapy, but also as an adoptive immunotherapeutic intervention capable of eradicating residual tumor cells in patients with cancer.

Early lymphocyte recovery after intensive timed sequential chemotherapy for acute myelogenous leukemia: peripheral oligoclonal expansion of regulatory T cells

Few published studies characterize early lymphocyte recovery after intensive chemotherapy for acute myelogenous leukemia (AML). To test the hypothesis that lymphocyte recovery mirrors ontogeny, we characterized early lymphocyte recovery in 20 consecutive patients undergoing induction timed sequential chemotherapy for newly diagnosed AML. Recovering T lymphocytes were predominantly CD4(+) and included a greatly expanded population of CD3(+)CD4(+)CD25(+)Foxp3(+) T cells. Recovering CD3(+)CD4(+)CD25(+)Foxp3(+) T cells were phenotypically activated regulatory T cells and showed suppressive activity on cytokine production in a mixed lymphocyte reaction. Despite an initial burst of thymopoiesis, most recovering regulatory T cells were peripherally derived. Furthermore, regulatory T cells showed marked oligoclonal skewing, suggesting that their peripheral expansion was antigen-driven. Overall, lymphocyte recovery after chemotherapy differs from ontogeny, specifically identifying a peripherally expanded oligoclonal population of activated regulatory T lymphocytes. These differences suggest a stereotyped immunologic recovery shared by patients with newly diagnosed AML after induction timed sequential chemotherapy. Further insight into this oligoclonal regulatory T-cell population will be fundamental toward developing effective immunomodulatory techniques to improve survival for patients with AML.

Immune mobilization of autologous blood progenitor cells: direct influence on the cellular subsets collected

BACKGROUND AIMS

A phase I trial examined the ability of immunotherapy to mobilize progenitor and activated T cells.

METHODS

Interleukin (IL)-2 was administered subcutaneously for 11 days, with granulocyte (G)-colony-stimulating factor (CSF) (5 mcg/kg/day) and granulocyte-macrophage (GM)-CSF (7.5 mcg/kg/day) added for the last 5 days. Leukapheresis was initiated on day 11. Thirteen patients were treated (myeloma n = 11, non-Hodgkin's lymphoma n = 2).

RESULTS

Toxicities were minimal. IL-2 was stopped in two patients because of capillary leak (n = 1) and diarrhea (n = 1). Each patient required 2.5 leukaphereses (median; range 1-3) to collect 3.2 x 10⁶ CD34+ cells/kg (median; range 1.9-6.6 x 10⁶/kg). Immune mobilization increased the number of CD3+ CD8+ T cells (P = 0.002), CD56+ natural killer (NK) cells (P = 0.0001), CD8+ CD56+ T cells (P = 0.002) and CD4+ CD25+ cells (P = 0.0001) compared with cancer patients mobilized with G-CSF alone. There was increased lysis of myeloma cells after 7 days (P = 0.03) or 11 days (P = 0.02). The maximum tolerated dose of IL-2 was 1 x 10⁶ IU/m²/day.

CONCLUSIONS

Immune mobilization is well tolerated with normal subsequent marrow engraftment. As cells within the graft influence lymphocyte recovery, an increased number of functional lymphocytes may result in more rapid immune reconstitution.

Early lymphocyte recovery and outcomes after umbilical cord blood transplantation (UCBT) for hematologic malignancies

Rapid lymphocyte recovery after bone marrow or peripheral blood transplantation is associated with improved survival. However, the impact of early lymphocyte recovery has not been examined after umbilical cord blood transplant (UCBT). We evaluated lymphocyte recovery in 360 consecutive patients with hematologic malignancy that underwent UCBT between 2001 and 2007. Uniform myeloablative (MA), reduced intensity conditioning (RIC) and graft-versus-host disease prophylaxis regimens were used. In multivariate analysis, an absolute leukocyte count (ALC) >200 × 10(6)/L at day 30 (n = 73) after MA conditioning was associated with superior 2-year overall survival (OS) (73% versus 61%; P = .02) (relative risk [RR]: 2.29; 95% confidence interval [CI]: 1.15-4.56), progression-free survival (PFS) (68% versus 54%; P = .05) (RR: 1.96; 95% CI: 0.99-3.86) and less transplant-related mortality (8% versus 28%, P < .01) (RR: 4.38; 95% CI: 1.65-11.60) compared to ≤200 × 10(6)/L (n = 43). Similarly, an ALC >200 × 10(6)/L at day 42 (n = 105) after RIC was associated with superior 2-year OS (59% versus 41%, P < .01) (RR: 2.10; 95% CI: 1.3-3.41) and PFS (46% versus 36%, P = .05) (RR: 1.58; 95% CI: 1.01-2.49) compared to ≤200 × 10(6)/L (n = 55). There was no significant relationship between ALC and relapse. Rapid lymphocyte recovery early after UCBT predicts better survival in patients with hematologic malignancies.

Intensive chemotherapy for acute myeloid leukemia differentially affects circulating TC1, TH1, TH17 and TREG cells

Background

Several observations suggest that immunological events early after chemotherapy, possibly during the period of severe treatment-induced cytopenia, are important for antileukemic immune reactivity in acute myeloid leukemia (AML). We therefore investigated the frequencies of various T cell subsets (T_C1, T_H1, T_H17) and CD25⁺ FoxP3⁺ T_REG cells in AML patients with untreated disease and following intensive chemotherapy.

Results

Relative levels of circulating T_C1 and T_H1 cells were decreased in patients with severe chemotherapy-induced cytopenia, whereas T_H17 levels did not differ from healthy controls. Increased levels of regulatory CD25⁺ FoxP3⁺ T cells were detected in AML patients with untreated disease, during chemotherapy-induced cytopenia and during regeneration after treatment. T_H17 and T_H1 levels were significantly higher in healthy males than females, but this gender difference was not detected during chemotherapy-induced cytopenia. Finally, exogenous IL17-A usually had no or only minor effects on proliferation of primary human AML cells.

Conclusions

We conclude that the effect of intensive AML chemotherapy differ between circulating T cell subsets, relative frequencies of T_H17 cells are not affected by chemotherapy and this subset may affect AML cells indirectly through their immunoregulatory effects but probably not through direct effects of IL17-A.

Interleukin-15 affects patient survival through natural killer cell recovery after autologous hematopoietic stem cell transplantation for non-Hodgkin lymphomas

Natural killer cells at day 15 (NK-15), after autologous peripheral blood hematopoietic stem cell transplantation (APHSCT), is a prognostic factor for overall survival (OS) and progression-free survival (PFS) in non-Hodgkin lymphoma (NHL). The potential role of the immunologic (homeostatic) environment affecting NK-15 recovery and survival post-APHSCT has not been fully studied. Therefore, we evaluate prospectively the cytokine profile in 50 NHL patients treated with APHSCT. Patients with an interleukin-15 (IL-15) ≥ 76.5 pg/mL at day 15 post-APHSCT experienced superior OS and PFS compared with those who did not; median OS; not reached versus 19.2 months, P < .002; and median PFS; not reached versus 6.8 months, P < .002, respectively. IL-15 was found to correlate with (r_s = 0.7, P < .0001) NK-15. Multivariate analysis showed only NK-15 as a prognostic factor for survival, suggesting that the survival benefit observed by IL-15 is most likely mediated by enhanced NK cell recovery post-APHSCT.

Influence of lymphocyte recovery on outcome of haploidentical transplantation for hematologic malignancies

Unmanipulated human leukocyte antigen (HLA)-mismatched/haploidentical blood and marrow transplantation is an established treatment for patients without HLA-matched related or unrelated donors. However, the prognostic significance of early lymphocyte recovery in this transplant setting is not defined. In this study, we investigated the association of day 30 absolute lymphocyte count (ALC-30) with outcome after unmanipulated HLA-mismatched/haploidentical transplantation. We prospectively analyzed the relationship between ALC-30 and transplant outcomes in 206 patients with hematologic malignancies receiving T-cell-replete transplantation from HLA-mismatched/haploidentical related donors. Multivariate analysis showed that ALC-30 above the cutoff value of 300 cells/microL was associated with improved overall survival (hazard ratio [HR], 0.258; 95% confidence interval [CI], 0.141-0.472; p < 0.0001); improved cancer-free survival (HR, 0.289; 95% CI, 0.166-0.501; p < 0.0001); reduced relapse (HR, 0.370; 95% CI, 0.161-0.853; p = 0.020); and decreased transplant-related mortality (HR, 0.211; 95% CI, 0.097-0.457; p < 0.0001). Our results suggest that the recovery of ALC-30 might have an influence on transplant outcomes following unmanipulated HLA-mismatched/haploidentical transplantation.

High CD8+ lymphocyte dose in the autograft predicts early absolute lymphocyte count recovery after peripheral hematopoietic stem cell transplantation

Early lymphocyte recovery (ELR) after autologous peripheral hematopoietic stem cell transplantation (ASCT) is an independent predictor for survival in patients with hematological and non-hematological cancers. Sixty-five ASCT for hematological cancers were retrospectively analyzed to identify the factors associated with ELR and to assess the impact of different mobilization regimens on the pre-collection absolute lymphocyte count (ALC). The CD8+ lymphocyte dose in the autograft and the pre-mobilization ALC were independently associated with ELR (P < 0.001 and P = 0.008, respectively). CD8+ lymphocyte doses higher than 0.1 x 10(9)/kg were strongly associated with ELR [P < 0.001, odds ratio 25.22, 95% confidence interval (CI) 4.98-127.69] and this cutoff may be used to predict ELR (P = 0.001, area under the curve 0.75, 95% CI 0.62-0.88). Mobilization with granulocyte colony-stimulating factor (G-CSF) alone, the pre-collection ALC and the number of apheresis sessions were independently associated with the CD8+ lymphocyte dose (P = 0.04, P = 0.001, and P < 0.001, respectively). The number of aphereses was the variable with the strongest correlation to the CD8+ lymphocyte dose (r(s) = 0.68, P < 0.001). Median pre-mobilization ALC was higher than pre-collection ALC in the subgroup of patients without ELR mobilized with chemotherapy followed by G-CSF (1090 vs. 758 lymphocytes/microL; P < 0.001). This reduction was not significant in the subgroup with ELR mobilized with chemotherapy plus G-CSF (1920 vs. 1539/microL, respectively; P = 0.23). These results suggest that the CD8+ lymphocyte dose in the autograft is critical for ELR after ASCT and also demonstrates that mobilization with chemotherapy followed by G-CSF significantly decreases the pre-collection ALC, especially in patients with low pre-mobilization ALC.

Early lymphocyte recovery predicts superior survival after autologous stem cell transplantation in non-Hodgkin lymphoma: a prospective study

Day 15 absolute lymphocyte count (ALC-15) after autologous peripheral blood hematopoietic stem cell transplantation (APHSCT) has been reported to be a significant predictor for survival in multiple hematologic malignancies. Limitations of previous reports included their retrospective nature and the lack of ALC-15 lymphocyte subset analyses. To address these limitations, from February 2002 until February 2007, 50 non-Hodgkin lymphoma (NHL) patients were enrolled in a prospective study. The primary endpoint of the study was to confirm prospectively the ALC-15 survival role after APHSCT in NHL. The secondary endpoint was to identify the ALC-15 lymphocyte subset affecting survival after APHSCT. With a median follow-up of 22.2 months (range: 6-63.7 months), patients with an ALC-15 > or =500 cells/microL (n = 35) experienced superior overall survival (OS) and progression-free survival (PFS) compared with those who did not; median OS: not reached versus 5.4 months, 3-year OS rates of 80% (95% confidence interval [CI]: 55%-95%) versus 37% (95% CI: 15%-65%), P < .0001; and median PFS: not reached versus 3.3 months, 3-year PFS rates of 63% (95% CI: 40%-85%) versus 13% (95% CI: 4%-40%), P < .0001, respectively. Univariately, CD16+/56+/CD3- natural killer (NK) cells were the only ALC-15 lymphocyte subset identified as a predictor for survival. Patients with an NK cell count > or =80 cells/microL (n = 38) experienced superior OS and PFS compared with those who did not (median OS: not reached versus 5 months, 3-year OS rates of 76% [95% CI: 57%-92%] versus 36% [95% CI: 11%-62%], P < .0001; and median PFS: not reached versus 3 months, 3-year PFS rates of 57% [95% CI: 38%-85%] versus 9% [95% CI: 1%-41%], P < .0001, respectively). Multivariate analysis showed that NK cells are an independent predictor for survival. This is the first study confirming the ALC-15 survival role prospectively and identifying NK cells as the key ALC-15 lymphocyte subset affecting survival after APHSCT.