Interleukin 4 responses in acute leukaemia patients with severe chemotherapy-induced leucopenia

Combined C-Reactive Protein and Novel Inflammatory Parameters as a Predictor in Cancer-What Can We Learn from the Hematological Experience?

The acute phase reaction is a systemic response to acute or chronic inflammation. The serum level of C-reactive protein (CRP) is the only acute phase biomarker widely used in routine clinical practice, including its uses for prognostics and therapy monitoring in cancer patients. Although Interleukin 6 (IL6) is a main trigger of the acute phase reactions, a series of acute phase reactants can contribute (e.g., other members in IL6 family or IL1 subfamily, and tumor necrosis factor α). However, the experience from patients receiving intensive chemotherapy for hematological malignancies has shown that, besides CRP, other biomarkers (e.g., cytokines, soluble cytokine receptors, soluble adhesion molecules) also have altered systemic levels as a part of the acute phase reaction in these immunocompromised patients. Furthermore, CRP and white blood cell counts can serve as a dual prognostic predictor in solid tumors and hematological malignancies. Recent studies also suggest that biomarker profiles as well as alternative inflammatory mediators should be further developed to optimize the predictive utility in cancer patients. Finally, the experience from allogeneic stem cell transplantation suggests that selected acute phase reactants together with specific markers of organ damages are useful for predicting or diagnosing graft versus host disease. Acute phase proteins may also be useful to identify patients (at risk of) developing severe immune-mediated toxicity after anticancer immunotherapy. To conclude, future studies of acute phase predictors in human malignancies should not only investigate the conventional inflammatory mediators (e.g., CRP, white blood cell counts) but also combinations of novel inflammatory parameters with specific markers of organ damages.

Immunosuppression and Immunotargeted Therapy in Acute Myeloid Leukemia - The Potential Use of Checkpoint Inhibitors in Combination with Other Treatments

INTRODUCTION

Immunotherapy by using checkpoint inhibitors is now tried in the treatment of several malignancies, including Acute Myeloid Leukemia (AML). The treatment is tried both as monotherapy and as a part of combined therapy.

METHODS

Relevant publications were identified through literature searches in the PubMed database. We searched for (i) original articles describing the results from clinical studies of checkpoint inhibition; (ii) published articles describing the immunocompromised status of AML patients; and (iii) published studies of antileukemic immune reactivity and immunotherapy in AML.

RESULTS

Studies of monotherapy suggest that checkpoint inhibition has a modest antileukemic effect and complete hematological remissions are uncommon, whereas combination with conventional chemotherapy increases the antileukemic efficiency with acceptable toxicity. The experience with a combination of different checkpoint inhibitors is limited. Thalidomide derivatives are referred to as immunomodulatory drugs and seem to reverse leukemia-induced immunosuppression, but in addition, they have direct inhibitory effects on the AML cells. The combination of checkpoint targeting and thalidomide derivatives thus represents a strategy for dual immunotargeting together with a direct antileukemic effect.

CONCLUSION

Checkpoint inhibitors are now tried in AML. Experimental studies suggest that these inhibitors should be combined with immunomodulatory agents (i.e. thalidomide derivatives) and/or new targeted or conventional antileukemic treatment. Such combinations would allow dual immunotargeting (checkpoint inhibitor, immunomodulatory agents) together with a double/triple direct targeting of the leukemic cells.

Effect of varicella zoster virus infection on bone marrow function

BACKGROUND

Most viral infections are known to exert adverse effects on bone marrow function. However, certain viruses have recently been found to be therapeutically beneficial in the treatment of some malignant disorders.

METHODS AND MATERIALS

A retrospective study was conducted at the Armed Forces Hospital, Riyadh, Saudi Arabia. The changes in the hematological parameters following varicella-zoster virus (VZV) infection in patients with a variety of hematological disorders were compared with those in a control group having the same spectrum of disorders and treated in the same unit over the same period of time but never had VZV infection. Both groups of patients received the same treatment protocols for their primary hematological disorders. Definitive treatment (DT) such as chemotherapy alone, anti-thymocyte globulin or bone marrow transplant was also employed in the management of patients belonging to both groups.

RESULTS

White blood cell counts, platelet counts and hemoglobin concentrations in the study group started to increase 40 d after chickenpox or herpes zoster infection and these increases lasted for periods as long as 1050 d. The changes in platelet counts were more pronounced than those in other hematological parameters. There was a significant difference (P < 0.0001) between the two groups of patients in the values of platelet counts achieved between 280 and 1050 d after DT (mean platelet count: 262 x 10(9)/L in the study group vs. 180 x 10(9)/L in the control group, median: 288.17 x 10(9)/L in the study group vs. 180 x 10(9)/L in the control group, range: 102 to 415 x 10(9)/L in the study group vs. 26 to 365 x 10(9)/L in the control group of patients). Compared to the control group, the study group of patients achieved their maximum blood counts much earlier after DT. The maximum leucocytic count was achieved at a mean duration of 269.21 d in the study group and 349.61 d in the control group. The maximum hemoglobin level was achieved at a mean duration of 319.5 d in the study group and 402.6 d in the control group. The maximum platelet count was achieved at a mean duration of 271.4 d in the study group and 318.9 d in the control group of patients.

CONCLUSION

VZV may behave differently from other members of the herpes group of viruses e.g. human cytomegalovirus and Epstein-Barr virus. Our observations suggest that VZV infection causes stimulation of bone marrow activity.

Characterization of Ribosomal P Autoantibodies in Relation to Cell Destruction and Autoimmune Disease

Autoantibodies against the ribosomal P proteins are related to cell death and tissue destruction and are frequently exhibited in patients with systemic lupus erythematosus (SLE). In an attempt to explore the effect of tissue destruction on the induction of anti-P autoantibodies, we searched for anti-P autoantibodies by enzyme-linked immunosorbent assay in 201 antinuclear antibody (ANA)-positive individuals, in 10 patients with treated kidney SLE and in 45 acute leukaemia patients undergoing intensive chemotherapy. The autoantibody reactivity was further characterized using one- and two-dimensional immunoblot analysis and immunofluorescence. Anti-P were detected in 5.5% (11/201) of ANA-positive individuals, but not in kidney-affected SLE patients or in patients with leukaemia. Seven of 11 anti-P-positive patients had SLE (3/11), primary Sjögrens's syndrome (1/11) and other autoimmune diseases (3/11). A relation between disease activity and anti-P was suggested by follow-up examinations in one SLE patient, supported by the absence of anti-P autoantibodies in the 10 treated kidney SLE patients. Anti-P autoantibodies were detected by immunoblot in one patient with SLE indicating anti-P2 predominance and in the patient with Sjögrens's syndrome indicating anti-P1 predominance. Diverging humoral responses in these ANA- and anti-P-positive patients were further illustrated by immunofluorescence, elucidating varying nuclear reactivity and anti-P pattern. The observation of anti-P in individuals with active autoimmune disease, but not in patients with chemotherapy-induced cell damage, suggests that anti-P antibodies are part of a specific disease process, and not elicited as a response to cell destruction per se.

Cellular immune responses in multiple myeloma patients with treatment-induced cytopenia early after high-dose chemotherapy and autologous peripheral blood stem cell transplantation

Proliferative T cell responses were compared for two patient groups with severe treatment-induced leukopenia (white blood cell counts < 0.5 x 10(9)/l): (i). multiple myeloma patients receiving high-dose melphalan and autologous peripheral blood stem cell transplantation; (ii). patients receiving conventional intensive chemotherapy for acute leukemia or myelodysplasia. Although the majority of circulating leukocytes were CD2(+)TCRalphabeta(+) in both groups, the myeloma patients showed significantly lower T cell proliferation in responses to several activation signals (anti-CD3, anti-CD3 + IL2, anti-CD3 + anti-CD28, anti-CD3 + anti-CD28+IL2. Our results suggest that myeloma patients with post-transplant cytopenia have a more severe cellular immune defect than patients with other hematological malignancies and severe cytopenia due to conventional intensive chemotherapy.

Immunologic monitoring of maintenance therapy for acute lymphoblastic leukaemia in children-preliminary report

BACKGROUND

In the study we evaluated immune reconstitution during maintenance therapy for acute lymphoblastic leukaemia (ALL) in relation to different treatment protocols and response of the immune system to the accompanying infections.

PROCEDURE

The study group consisted of 40 children. The BFM protocol'90 was used in the standard risk group, while the New York protocol-in the high risk group. Assessment of the immune system was based on the analysis of peripheral blood mono-nuclear cells by flow cytometry and concentrations of immunoglobulins: G, M, A and IgE. Each patient was examined at 1-3 months' intervals.

RESULTS

Following cessation of intensive therapy, the successive months of maintenance treatment showed: (1) a considerable depletion of B lymphocytes, a durable decrease in IgM, IgA and gradually increasing IgG; (2) a correlation between the time passing from the cessation of intensive therapy and increased numbers and percentage of B cells, and the helper/suppressor cell ratio. In the group of children treated according to the high risk protocol, compared to the low-risk group patients, we found lower levels of the following parameters: IgG, % lymphocytes: B and T lymphocytes (including CD4/CD8 ratio and "naive"/"memory" ratio) and NK cells (% and count). During infection: (1) a significant increase was noted in the percentage of T cells with HLA co-expression and monocytes with ICAM-1 co-expression, (2) the percentage of CD3(+)CD45RO(+) "memory" T cells was found to increase.

CONCLUSIONS

Our findings indicate quantitative and qualitative changes of the immunity in children with ALL during maintenance therapy.

Interleukin-7 (IL-7) in patients receiving intensive chemotherapy for acute myelogenous leukemia: studies of systemic IL-7 Levels and IL-7 responsiveness of circulating T lymphocytes

Early immune reconstitution after intensive chemotherapy for acute myelogenous leukemia (AML) occurs after 2-4 weeks of cytopenia, but T cell reconstitute is usually completed after several months. Interleukin-7 (IL-7) is a T cell growth factor involved in the late immune reconstitution, but its function during the early period of cytopenia has not been investigated. In the present study, we found that patients with untreated AML had decreased IL-7 serum levels, and induction chemotherapy had divergent effects on these levels. In contrast, patients in complete remission (CR) had intermediate levels immediately before consolidation therapy, and these levels decreased significantly when the patients developed therapy-induced cytopenia. Systemic IL-7 levels showed only minor increases during febrile neutropenia. Furthermore, IL-7 enhanced in vitro proliferative responses of polyclonal T cells derived from cytopenic patients, and the majority of circulating clonogenic CD4(+) and CD8(+) T cells from cytopenic patients could respond to both IL-2 and IL-7. To conclude, patients with untreated AML and severe chemotherapy-induced leukopenia (1) differ from other patients with CD4(+) T lymphopenia in that they show decreased IL-7 serum levels, and (2) the detection of circulating IL7-responsive T cells indicates that variations in systemic IL-7 levels are functionally important and contribute to an additional qualitative T cell defect in these severely T lymphopenic patients.

Effects of azoles on human acute myelogenous leukemia blasts and T lymphocytes derived from acute leukemia patients with chemotherapy-induced cytopenia

The effects of azoles (fluconazole, ketoconazole, miconazole, itraconazole) on human acute myelogenous leukemia (AML) blasts and T lymphocytes were studied in vitro. All the azoles altered spontaneous proliferation, cytokine-dependent proliferation and constitutive cytokine secretion by native AML blasts for a subset of patients, and all the drugs then had divergent effects. All four drugs also affected the responsiveness (cytokine-dependent and mitogen-stimulated proliferation, cytokine release) of clonogenic CD4+ and CD8+ T cells derived from acute leukemia patients with chemotherapy-induced cytopenia. However, the T cell effects were also divergent and dependent on differences between various azoles, AML accessory cells and mitogenic activation signals. These drug effects may have a clinical relevance in acute leukemia patients receiving intensive chemotherapy together with azoles as prophylaxis or treatment for fungal infections: (i) effects on AML blasts may influence their susceptibility to drug-induced apoptosis; and (ii) effects on T cells may alter effector functions that mediate additional antileukemic effects in patients receiving intensive chemotherapy.

Biological treatment in acute myelogenous leukaemia: how should T-cell targeting immunotherapy be combined with intensive chemotherapy?

T-cell targeting immunotherapy is now considered as a possible strategy in the treatment of acute myelogenous leukaemia (AML). Clinical importance of antileukaemic T-cell reactivity after allogeneic stem cell transplantation (SCT) is well established and the early experience from IL-2 therapy suggests that even autologous T-cells can mediate antileukaemic reactivity. The clinical experience also indicates that immunotherapy should begin when the leukaemia cell burden is minimal, and the detection of an operative cellular immune system, even in patients with chemotherapy-induced cytopenia, further suggests that it is possible to begin T-cell targeting therapy early after chemotherapy while patients are still cytopenic. However, adult patients in particular have a T-cell defect after chemotherapy that may last for several months. For this reason immunotherapy should probably be continued or repeated until a maximal effect is achieved when the patients no longer have a T-cell defect. This treatment approach may also be considered in combination with autologous SCT. T-cell targeting regimens should include, if possible, several therapeutic components. Firstly, native AML blasts can function as accessory cells during T-cell activation and in vivo therapy with T-cell growth factors (e.g., IL-2, IL-15) may then enhance antileukaemic reactivity or non-specific cytotoxicity against the AML cells; and secondly, a further enhancement of AML-specific reactivity may be achieved by vaccination with AML-specific peptides, immunisation with AML-blasts expressing a dendritic cell phenotype, or exposure to normal antigen-presenting cells (APC) pulsed with or expressing AML-specific peptide sequences.

Effects of imipenem and cilastatin on human T-lymphocytes derived from acute leukemia patients with chemotherapy-induced leucopenia: studies of T-lymphocyte responses in the presence of acute myelogenous leukemia (AML) blast accessory cells

The effects of imipenem and cilastatin on human T-lymphocytes were studied in vitro. As responder T-cells were used T-lymphocyte clones derived from acute leukemia patients with chemotherapy-induced cytopenia, and the accessory cells were highly enriched acute myelogenous leukemia (AML) blasts. The effects of imipenem and cilastatin on phytohemagglutinin (PHA), anti-CD3 and anti-CD3+anti-CD28 stimulated activation were assayed, and in addition drug effects on cytokine-dependent proliferation of activated T-lymphocytes were investigated. Imipenem inhibited IL2-dependent proliferation of activated CD4(+) and CD8(+) T-cell clones, and an inhibition was also detected for IL7-, IL12-, IL15-, IL16- and IL17-dependent clonal proliferation. Imipenem caused a weak inhibition of anti-CD3- and PHA-stimulated T-cell proliferation when using 50 Gy irradiated AML blast accessory cells derived from various patients, whereas no effect was observed for anti-CD3+anti-CD28 stimulated and allostimulated activation. Imipenem decreased the release of IL4 and Interferon-gamma by T-cell clones stimulated with anti-CD3 and PHA in the presence of native (nonirradiated) AML blasts. The imipenem effects were observed at concentrations corresponding to levels reached in vivo, whereas even high concentrations of cilastatin did not alter T-cell responses. The T-lymphocyte inhibition is probably caused by a direct effect of imipenem on the T-cells.