Lymphocyte function after autologous bone marrow transplantation (BMT): a comparison with patients treated with allogeneic BMT and with chemotherapy only

[Seroconversion in response to a reinforced primary hepatitis B vaccination in children with cancer]

INTRODUCTION

Immune response against vaccine antigens may be impaired in children with cancer. The aim of this study was to evaluate the seroconversion response against hepatitis B vaccination (HBV) at the time of chemotherapy onset and/or remission in children with cancer.

PATIENTS AND METHOD

Prospective, two-centre, controlled, non-randomised study conducted on children recently diagnosed with cancer, paired with healthy subjects. Cases received HBV at time 0, 1 and 6 months with DNA recombinant HBV at a dose of 20 and 40 μg if < or > than 10 years of age, respectively, at the time of diagnosis for solids tumours and after the remission in case of haematological tumours. Controls received the same schedule, but at of 10 and 20 μg doses, respectively. HBs antibodies were measured in serum samples obtained at 2, 8 and 12 months post-vaccination. Protective titres were defined as > 10 mIU/ml at 8th month of follow up.

RESULTS

A total of 78 children with cancer and 25 healthy controls were analysed at month 8th of follow up. Seroconversion rates in the cancer group reached 26.9%, with no differences by age, gender or type of tumour (P = .13, .29, and .44, respectively). Control group seroconversion was 100% at the 8th month, with P < .0001 compared with the cancer group. At month 12 of follow up, just 31.9% of children with cancer achieved anti-HBs antibodies > 10 mIU/ml.

CONCLUSIONS

Vaccination against hepatitis B with three doses of DNA recombinant vaccine at an increased concentration, administrated at the time of onset of chemotherapy and/or remission provided an insufficient immune response in a majority of children with cancer. More immunogenic vaccines should be evaluated in this special population, such as a third generation, with more immunogenic adjuvants, enhanced schedules at 0, 1, 2, 6 month, evaluation of antibody titres at month 8 and 12h to evaluate the need for further booster doses.

Randomized trial of low-dose interleukin-2 vs cyclosporine A and interferon-γ after high-dose chemotherapy with peripheral blood progenitor support in women with high-risk primary breast cancer

High-risk primary breast cancer patients treated with high-dose chemotherapy (HDC) and stem cell support (SCS) have shown prolonged disease-free survival (DFS) in many studies; however, only one trial has demonstrated an overall survival benefit (OS). We hypothesize that the period following myeloablative therapy is ideal for immunologic manipulation and studied the effects of two different methods of immunotherapy following HDC with SCS aimed at the window of immune reconstitution. Seventy-two women with high-risk stage II or III breast cancer were randomized following HDC to receive either interleukin 2 (IL-2) at 1 million units/m(2) SQ daily for 28 days or combined cyclosporine A (CsA) at 1.25 mg/kg intravenously daily from day 0 to +28 and interferon gamma (IFN-gamma) 0.025 mg/m(2) SQ every 2 days from day +7 to +28. At a median follow-up of 67 months, no significant difference was observed in DFS or OS between the two treatment groups. The IL-2 arm had a 59% DFS (95% CI (0.45, 0.78)) and a 72% OS (95% CI (0.58, 0.88)) at 5 years. The CsA/INF-gamma arm had a similar outcome with a 55% DFS (95% CI (0.40, 0.76)) and a 78% OS (95% CI (0.65, 0.94)) at 5 years. Treatment was well tolerated, without increased toxicity.

Rapid immune reconstitution following autologous hematopoietic stem cell transplantation in children: a single institution experience

In this retrospective study, we review the immune reconstitution of children undergoing autologous hematopoietic stem cell transplantation. A total of 125 patients underwent autologous transplantation between 1992 and 2000. The report includes data on 58 patients. Data were not available on the remaining patients who either died before testing or data were not obtained. The parameters evaluated include: (a) immunophenotype by flow cytometry to quantify lymphocyte subpopulations (b) mitogen stimulation assays, and (c) quantitative immunoglobulins. The analysis reveals that CD3+ cells did not reach the normal range during the first year post-transplant. The median percentage of CD4+ cells was below normal up to 6 months post-transplant, while the absolute number remain low throughout the first year. The CD8+ percentage and absolute numbers remain normal at all times post-transplant. The CD19+ cells were also normal post-transplantation. The mitogen lymphocyte stimulation was normal in 27 out of 31 patients tested after 6 months post-transplant. Our analysis of immune reconstitution shows a similar pattern to previous studies with a faster recovery of the CD4/CD8 ratio, especially in those patients who did not receive TBI. In conclusion, the observed deficiencies are transient and have very little clinical significance because, historically, the rate of serious infections is low despite prolonged immune suppression. The recovery post-autologous transplant is fast.

Current chemotherapy protocols for childhood acute lymphoblastic leukemia induce loss of humoral immunity to viral vaccination antigens

OBJECTIVE

To evaluate viral vaccination immunity and booster responses in children treated successfully for acute lymphoblastic leukemia by chemotherapy and to study the response to treatment of antibody-producing plasma cells that are important for persistence of humoral immunity.

METHODS

Forty-three children who were in continuous first remission for a median of 5 years (range: 2-12 years) were studied. Before the leukemia was diagnosed, all children had been immunized against measles, mumps, and rubella according to the Swedish National immunization program. We analyzed levels of serum antibodies against measles and rubella by enzyme immunoassays. Avidity tests for measles antibodies were concomitantly performed by enzyme-linked immunosorbent assay for measles virus immunoglobulin G detection. The proportion of plasma cells in bone marrow was studied by flow cytometry at different times during treatment and follow-up. Children who lacked protective levels of antibodies to vaccination antigens were reimmunized. Serum was collected 3 months after immunization to assess vaccination responses.

RESULTS

After completion of the treatment, only 26 of the 43 children (60%) were found to be immune against measles and 31 (72%) against rubella. The proportion of bone marrow plasma cells decreased during treatment but returned to normal after 6 months. Revaccination caused both primary and secondary immune responses. Six of the 14 children without immunity failed to achieve protective levels of specific antibodies against measles and 3 against rubella.

CONCLUSIONS

Our finding of loss of antibodies against measles and rubella in children treated with intensive chemotherapy suggests that reimmunization of these patients is necessary after completion of the treatment. To determine reimmunization schedules for children treated with chemotherapy, vaccination responses need to be studied further.

[Immunization for children treated for solid tumors: what are the guidelines?]

There is no agreement on immunization of children treated with chemotherapy (CT) for solid tumors. Based on a review of the literature, we have attempted to establish guidelines on this subject. Except for hepatitis B vaccine, there is no argument to support the use of vaccine during CT. After a standard CT, a 3-month washout period appears to be necessary before starting an immunization program for a child not previously vaccinated, or to proceed with the recommended booster injections for diphteria anatoxin, tetanus vaccine, poliomyelitis inactivated vaccine, pertussis vaccine, and haemophilus influenza type b vaccine if the child is less than 5 years old. For mumps, measles, and rubella live vaccines, a longer post-CT washout of 6 months is suggested for the initial immunization, or for a revaccination of a child proved to be negative for all three serologies. Following high-dose CT a minimal 12-months term and a normalization of the blood lymphocytes count is necessary before planning booster injections once having checked for antidiphteria, tetanic, polio, measles, mumps, rubella and +/- haemophilus antibody titles. We don't find any reason to recommend a systematic varicella immunization in pediatric oncology. Pneumococcal vaccine is recommended in case of asplenia. Any other vaccination (BCG, influenza, yellow fever) must be evaluated individually.

Transplantation with selected autologous peripheral blood CD34+Thy1+ hematopoietic stem cells (HSCs) in multiple myeloma: impact of HSC dose on engraftment, safety, and immune reconstitution

OBJECTIVE

The aims of our study performed in myeloma were to evaluate the performance and the safety of Systemix's high-speed clinical cell sorter, to assess the safety and efficacy of deescalating cell dose cohorts of CD34+Thyl+ hematopoietic stem cells (HSCs) as autologous grafts by determining engraftment, and to assess the residual tumor cell contamination using polymerase chain reaction (PCR) amplification assays of patient-specific complementarity determining region III (CDR III) analysis for residual myeloma cells.

MATERIALS AND METHODS

The clinical trial was performed in 31 multiple myeloma patients, using purified human CD34+Thyl+ HSCs mobilized from peripheral blood with cyclosphosphamide and granulocyte-macrophage colony-stimulating factor to support a single transplant after high-dose melphalan 140 mg/m2 alone (cohort 1) and with total body irradiation (TBI) (cohorts 2-5) after an HSC transplant cell dose de-escalation/escalation design.

RESULTS

Twenty-three patients were transplanted. Engraftment data in the melphalan + TBI cohorts confirmed that HSC doses above the threshold dose of 0.8 x 10(6) CD34+Thy1+ HSCs/ kg provided prompt engraftment (absolute neutrophil count >0.5 x 10(9)/L day 10; platelet count >50 x 10(9)/L day 13). A higher rate of infections was observed in the early and late follow-up phases than usually reported after CD34+ selected or unselected autologous transplantation, which did not correlate with the CD34+Thy1+ HSC dose infused. Successful PCR for CDR III could only be performed in five patients on initial apheresis product and final CD34+Thy1+ HSC product and showed a median tumor log reduction >3.12.

CONCLUSIONS

CD34+Thy1+ HSCs are markedly depleted or free of detectable tumor cells in multiple myeloma and are capable of producing fast and durable hematopoietic reconstitution at cell doses >0.8 x 10(6) CD34+Thy1+ HSCs/kg. The delayed immune reconstitution observed is not different from that described in unselected autologous bone marrow and peripheral blood mononucleated cells transplants in multiple myeloma and may be corrected by addition of T cells either to the graft or to the patient in the posttransplant phase.

Requirement of residual thymus to restore normal T-cell subsets after human allogeneic bone marrow transplantation

BACKGROUND

To determine the effect of residual thymic activity in reconstituting the T-cell system after T cell-depleting therapy, we monitored T-cell subsets of a unique thymectomized cancer patient in comparison to thymus-bearing patients after allogeneic bone marrow transplantation (BMT).

METHODS

T cells and T-cell subsets previously shown in murine studies to be regulated by the thymus were analyzed by FACS from 6 to >48 months after BMT. The investigation of thymus-bearing patients included 32 examinations of 9 children and 14 adults. None of the investigated cases had severe graft-versus-host disease or severe infections when examined.

RESULTS

In the thymectomized host, T-cell regeneration occurred by donor cell expansion and was characterized by two prominent features: (i) a persistent failure to regenerate naive (CD45RA+) T-helper cells (14%, median), consistent with the recently developed concept of a thymus-dependency; and (ii) persistently elevated proportions of CD3+CD4-CD8- cells (double-negative cells, median 29%), which were identified in T cell receptor (TCR)gamma delta+ (22%, median of CD3+ cells, 88% double negatives) but also TCRalpha beta+ T-cell populations (78%, median of CD3+ cells, 17% double negatives). In thymus-bearing patients, 10 of 12 and 6 of 14 examinations of children and adults, respectively, performed later than 12 months after BMT showed the proportion of CD4+CD45RA+ cells appropriate for age (>52% and >28% in children and adults, respectively). Elevated double-negative cells (>10%) were found in only three patients, but none had elevated double-negative cells with a TCRalpha beta+ phenotype.

CONCLUSION

Residual thymic activity might, in addition to its well-established role for regenerating naive T-helper (CD4+CD45RA+) cells, control the expansion of double-negative cells. A normal T-cell subset regeneration in a proportion of thymus-bearing adult hosts indicates the potential of an effective residual thymic activity even beyond childhood.

Immune reconstitution after autologous purged bone marrow transplantation in children

PURPOSE

Immune reconstitution was studied in 30 children who had received purged autologous bone marrow transplantation for neuroblastoma or acute myeloid leukemia (AML).

METHODS

Patients with neuroblastoma received high-dose chemotherapy and total body irradiation, and patients with AML received chemotherapy alone. Marrows were purged ex vivo with either antineuroblastoma monoclonal antibodies (neuroblastoma) or 4-hydroperoxycyclophosphamide (AML). Lymphocyte subsets, mitogen stimulation studies, and immunoglobulin levels were studied every 4 months.

RESULTS

There were no significant differences between the two groups of patients in lymphocyte number or subsets over time. In both groups, CD2+ and CD4+ cells were below normal in 33% of patients at 12 months. CD4+/CD8+ ratios were below normal for up to 8 months after transplantation and natural killer cells were elevated for up to 2 years in most patients. Median IgG and IgA levels were below the age mean even at 2 years after transplantation, although patients with AML had significantly higher IgG levels at 12 months compared with those with neuroblastoma. Lymphocyte proliferative responses to mitogens were markedly reduced at 4 months but returned to normal at 8 months. Despite the delay in immune reconstitution, there were no life-threatening infections.

CONCLUSIONS

There appeared to be little difference in the overall kinetics of immune reconstitution between the children with neuroblastoma, who received total body irradiation and high-dose chemotherapy, and those with AML, who received high-dose chemotherapy alone as their pretransplant preparative regimen.

Minimal residual disease in acute myelogenous leukemia with PML/RAR alpha or AML1/ETO mRNA and phenotypic analysis of possible T and natural killer cells in bone marrow

Here we studied minimal residual disease (MRD) of patients with acute myeloid leukemia (AML) who have PML/RAR alpha or AML1/ETO as well as the phenotypic analysis of lymphocyte subsets involved in antitumor immunity. Eight patients in long-term (LT; 3 to 15 years) and 15 patients in short-term (ST; up to 3 years) remission were studied. Using the reverse transcription-polymerase chain reaction (RT) assay, the limit of detection was 10(-5) to 10(-6) for PML/RAR alpha transcript and 10(-4) to 10(-5) for the AML1/ETO transcript. Simultaneously, T lymphocyte subsets and NK cells from the peripheral blood (PB) and bone marrow (BM) were investigated by flow cytometric analysis. Four of the eight patients in LT and 7 of the 15 patients in ST remission were MRD-positive. Although all MRD-positive patients in LT remission are still until now event-free, 3 of the 7 MRD-positive (MRD+) patients in ST remission soon relapsed. The total populations of CD4+, CD8+ and CD56+ [possible T-cell and natural killer (T/NK) populations] in the BM of ST patients and MRD+/LT patients were significantly (p < .01) low. The CD8+ CD28+ population showed the same tendency (p < .01-.02). The T/NK subsets in the BM of MRD-negative (MRD-) LT (MRD-/LT) patients showed similar numbers of cells as normal volunteers. Basically, the total percentage of the CD4+, CD8+ and CD56+ cell populations in the BM was increased and in the following order: MRD-/LT patients, normal volunteers, MRD+/LT patients and MRD+ or -/ST patients. The percentages of the T/NK-cell subsets in the PB were not significantly different among these groups. Thus, the difference of the possible T/NK-cell phenotype in the BM may strongly influence clinical and molecular remission. These results still remain to be confirmed by further studies of the functional anti-tumor immunity of T/NK cells of AML in remission.

Modulatory function on autologous myeloid progenitor cells of clonal T-lymphocytes following autologous bone marrow transplantation

We have studied the regulatory capacity of clonal T-lymphocytes from patients undergoing autologous bone marrow transplantation (ABMT) on the generation of CFU-GM from their harvest marrow preparations. To this end, T-lymphocytes from peripheral blood from 5 patients undergoing ABMT isolated 10 d before and 7, 14 and 28 d post-ABMT were placed in limiting dilution conditions (384 wells for each patient at each time point) and polyclonally stimulated. From more than 1600 wells with growth from the 5 patients, preparations from more than 900 wells could be expanded (range between patients 33-452) and identified by immunophenotyping (IP) and flow cytometry (FCM) by their exclusive expression of CD4 or CD8. This was significantly fewer than seen in normal donors, especially so at d 7 and 14 post-ABMT The ratio between CD4+ and CD8+ clones varied between 0.6 and 2.8 (median 1.3) and was significantly lower in the patients compared to normal donors (median 3.1; range 3.0-6.5). When the clonal T-cell preparations were co-cultured with autologous bone marrow cells obtained at the time of harvest and depleted for T-lymphocytes, the vast majority of both CD4+ and CD8+ clones exerted a clear enhancement on the CFU-GM growth with no relation to time of blood sampling in its the magnitude. Moreover, a trend seen in the normal donors towards CD4+ clones being more effective in this enhancement was not observed in ABMT patients. We conclude that clonal T-cells from ABMT patients, irrespective of their phenotype and time of isolation, exert an enhancement on the growth of autologous CFU-GM, which is equal to that seen in normal donors.

Recovery of blood T-cell subsets after chemotherapy for childhood acute lymphoblastic leukemia

Recovery of cell-mediated immunity after cessation of chemotherapy for childhood acute lymphoblastic leukemia (ALL) was investigated in 14 children to monitor the duration of immune deficiency. The numbers of blood T cells and their subsets were analyzed at 0, 1, 3, 6, 9 and 12 months after discontinuation of therapy with monoclonal antibodies and flow cytometry. The total T-cell count was low at cessation but normalized at 1 to 3 months, whereas the T-cell subsets CD4+, CD8+, CD4+Leu8-, and CD4+CD45RA+ recovered differently. In children ages 3 to 6 years, the numbers of CD4+ cells and their subsets were normal at cessation, whereas in children ages 7 to 18 years, CD4+ and CD4+Leu8+ cell counts normalized only at 6 months. The numbers of CD8+ cells or activated T cells were not increased and the CD4+/CD8+ ratio was not inverted, unlike recovery after bone marrow transplantation. Although the groups showed a mean reversion to normal values by 6 months, there were individual patients who continued to have subnormal values for 1 year after therapy, some of whom exhibited increased susceptibility to infections.

Recovery of blood lymphocytes and serum immunoglobulins after treatment of solid tumors in children

Hematologic and immunologic recovery after treatment for different solid tumors was investigated in 11 children at cessation of therapy and at 1, 3, 6, 9, and 12 months after cessation of therapy by determining blood total leukocyte counts, leukocyte differentials, lymphocyte subsets, concentrations of serum immunoglobulins (Igs), and serum IgG subclasses. Lymphocyte subsets were analyzed from mononuclear cell fractions by flow cytometry and use of monoclonal antibodies CD3, CD20, CD4, CD8, CD4/Leu-8, and CD4/CD45RA. Peripheral blood total leukocyte, neutrophil, and B-cell counts recovered early, although defective B-cell function was seen in several patients. T-cell counts and thus total lymphocyte counts required a longer time to normalize even though inducer T-cell subsets (CD4+CD45RA+ and CD4+Leu-8-) were present in normal or high amounts. CD8+ T cells recovered earlier than CD4+ T cells. The lymphocyte, B-cell and T-cell counts of most patients normalized during the first 12 months after therapy. Recovery of total lymphocyte and T-cell counts was slow in patients with Hodgkin's disease or Burkitt's lymphoma and rapid in nephroblastoma. Radiotherapy seemed to prolong the recovery of study parameters, particularly T-cell recovery.

Blunted rise in intracellular calcium in CD4+ T cells in response to mitogen following autologous bone marrow transplantation

Following autologous bone marrow transplantation (ABMT), both impaired T cell activation and defective production of the principal T cell growth factor, interleukin-2 (IL-2), has been observed. These processes are dependent on a rise of intracellular calcium ([Ca2+]i), a step which follows binding of T cell receptor (TCR) and transduction of signal via the generation of cytoplasmic second messengers. In order to better understand the nature of defective cellular immunity in ABMT, in the present study we investigated the rise of [Ca2+]i in T cells of recipients of ABMT. By concomitant labelling lymphocytes with anti-CD4 antibody and addition of fluo-3 as fluorescent calcium indicator, we have selected for the T cell subset which is the principal source of IL-2. Short-term (less than 1 year post-transplantation) recipients of ABMT show a statistically significant blunted rise in [Ca2+]i in response to concanavalin A as compared to normal controls not accounted for solely by a decreased percentage of CD4+ cells in these patients. The [Ca2+]i response of CD4+ cells from long-term (greater than 1 year post-transplant) recipients was lower than that of the normal group although not to a statistically significant level. These findings suggest that following ABMT is a defect in the early stages of T cell activation involving either T cell receptor binding or early signal transduction ultimately resulting in depressed transcription of IL-2 mRNA. These defects are analogous to findings in both allogeneic transplantation where factors of histoincompatibility and graft-versus-host disease (GVHD) come into play, as well as in the defective T cell activation of the normal ageing process.

Immunological reconstitution after high-dose chemotherapy and autologous blood stem cell transplantation for advanced ovarian cancer

We evaluated the immunological reconstitution of patients who underwent high-dose chemotherapy and autologous blood stem cell transplantation (ABSCT) for advanced ovarian cancer. Sixty days after transplantation a complete reconstitution of lymphocytes and of the CD3, CD4, CD8, CD19, and CD16/56 subsets was observed in this series. A significant increase in the count of interleukin-2 receptor expressing lymphocyte (CD25) was found on day +60 after transplantation compared to that obtained at diagnosis and before transplantation. A significantly higher lymphokine-activated killer (LAK) precursor activity was seen on day +60 compared to the values obtained at diagnosis and before transplantation while natural killer activity did not show any significant variation. We conclude that ABSCT gives prompt and complete immunohaematopoietic reconstitution after high-dose treatment. Moreover, our data support the feasibility of interleukin-2/LAK therapy as consolidative therapy after ABSCT.

Recovery of blood B-lymphocytes and serum immunoglobulins after chemotherapy for childhood acute lymphoblastic leukemia

Recovery of humoral immunity after cessation of chemotherapy for childhood acute lymphoblastic leukemia (ALL) was investigated by determining blood leukocyte, lymphocyte and B-lymphocyte, and serum immunoglobulin (Ig) levels and IgG subclasses at 0, 1, 3, 6, 9, and 12 months after cessation of chemotherapy for ALL in 14 patients. Blood B-lymphocytes were analyzed with the use of flow cytometry and monoclonal CD20 antibody. At cessation of chemotherapy, the amount of blood B-lymphocytes was subnormal in most patients but increased to normal levels in 1 month after therapy was discontinued. The recovery of serum Ig, which reflect B-cell function, was slower, but occurred by 6 months after therapy was discontinued in most patients. The authors conclude that by 6 months after cessation of chemotherapy for ALL, a sufficiently functioning immune system by these parameters is established and that prophylactic antibiotics can be withdrawn and immunizations started.

B lymphocyte regeneration in marrow and blood after autologous bone marrow transplantation: increased numbers of B cells carrying activation and progression markers

The reconstitution of B cells in the bone marrow and peripheral blood was prospectively studied in 27 patients undergoing autologous bone marrow transplantation (ABMT). No major differences in B cell regeneration patterns were recorded between patients receiving marrows purged of B cells (anti-CD10 + 19; n = 17) and patients receiving unpurged marrows (n = 10). Compared with healthy controls, elevated absolute and relative numbers of B cells were recorded in the blood and marrow at +6 and +12 months in both groups of patients. CD23+ B cells were severely depressed during the first three months post ABMT, indicating immaturity. A twofold increase in B cells carrying the activation marker 4F2 was recorded in the marrow at +1 month. Serum immunoglobulin levels (IgG, IgA, IgM) were within low-normal range throughout the study. The depressed B cell responses reported after allogeneic and autologous BMT could in part be explained by the low expression of the CD23 antigen on B cells after such therapy.