Claude Sportes

IL-7 administration to humans leads to expansion of CD8+ and CD4+ cells but a relative decrease of CD4+ T-regulatory cells

Lymphopenia is a serious consequence of HIV infection and the administration of cancer chemotherapeutic agents. Although growth factors can be administered to patients to increase circulating neutrophils, there is no effective method to stimulate CD8+ lymphocyte production in humans, in vivo. This report is the first to describe the administration of recombinant interleukin-7 to humans and demonstrates the ability of this cytokine to mediate selective increases in CD4+ and CD8+ lymphocytes along with a decrease in the percentage of CD4+ T-regulatory cells. These studies suggest an important role for interleukin-7 in the treatment of patients with lymphopenia.

Donor-derived CD19-targeted T cells cause regression of malignancy persisting after allogeneic hematopoietic stem cell transplantation

New treatments are needed for B-cell malignancies persisting after allogeneic hematopoietic stem cell transplantation (alloHSCT). We conducted a clinical trial of allogeneic T cells genetically modified to express a chimeric antigen receptor (CAR) targeting the B-cell antigen CD19. T cells for genetic modification were obtained from each patients alloHSCT donor. All patients had malignancy that persisted after alloHSCT and standard donor lymphocyte infusions (DLIs). Patients did not receive chemotherapy prior to the CAR T-cell infusions and were not lymphocyte depleted at the time of the infusions. The 10 treated patients received a single infusion of allogeneic anti-CD19-CAR T cells. Three patients had regressions of their malignancies. One patient with chronic lymphocytic leukemia (CLL) obtained an ongoing complete remission after treatment with allogeneic anti-CD19-CAR T cells, another CLL patient had tumor lysis syndrome as his leukemia dramatically regressed, and a patient with mantle cell lymphoma obtained an ongoing partial remission. None of the 10 patients developed graft-versus-host disease (GVHD). Toxicities included transient hypotension and fever. We detected cells containing the anti-CD19-CAR gene in the blood of 8 of 10 patients. These results show for the first time that donor-derived allogeneic anti-CD19-CAR T cells can cause regression of B-cell malignancies resistant to standard DLIs without causing GVHD.

Phase I Study of Recombinant Human Interleukin-7 Administration in Subjects with Refractory Malignancy

Purpose: Interleukin-7 (IL-7) has critical and nonredundant roles in T-cell development, hematopoiesis, and postdevelopmental immune functions as a prototypic homeostatic cytokine. Based on a large body of preclinical evidence, it may have multiple therapeutic applications in immunodeficiency states, either physiologic (immunosenescence), pathologic (HIV), or iatrogenic (postchemotherapy and posthematopoietic stem cell transplant), and may have roles in immune reconstitution or enhancement of immunotherapy. We report here on the toxicity and biological activity of recombinant human IL-7 (rhIL-7) in humans. Design: Subjects with incurable malignancy received rhIL-7 subcutaneously every other day for 2 weeks in a phase I interpatient dose escalation study (3, 10, 30, and 60 μg/kg/dose). The objectives were safety and dose-limiting toxicity determination, identification of a range of biologically active doses, and characterization of biological and, possibly, antitumor effects. Results: Mild to moderate constitutional symptoms, reversible spleen and lymph node enlargement, and marked increase in peripheral CD3+, CD4+, and CD8+ lymphocytes were seen in a dose-dependent and age-independent manner in all subjects receiving ≥10 μg/kg/dose, resulting in a rejuvenated circulating T-cell profile, resembling that seen earlier in life. In some subjects, rhIL-7 induced in the bone marrow a marked, transient polyclonal proliferation of pre-B cells showing a spectrum of maturation as well as an increase in circulating transitional B cells. Conclusion: This study shows the potent biological activity of rhIL-7 in humans over a well-tolerated dose range and allows further exploration of its possible therapeutic applications. Clin Cancer Res; 16(2); 727–35

Characterization and treatment of chronic active Epstein-Barr virus disease: a 28-year experience in the United States

Chronic active EBV disease (CAEBV) is a lymphoproliferative disorder characterized by markedly elevated levels of antibody to EBV or EBV DNA in the blood and EBV RNA or protein in lymphocytes in tissues. We present our experience with CAEBV during the last 28 years, including the first 8 cases treated with hematopoietic stem cell transplantation in the United States. Most cases of CAEBV have been reported from Japan. Unlike CAEBV in Japan, where EBV is nearly always found in T or natural killer (NK) cells in tissues, EBV was usually detected in B cells in tissues from our patients. Most patients presented with lymphadenopathy and splenomegaly; fever, hepatitis, and pancytopenia were common. Most patients died of infection or progressive lymphoproliferation. Unlike cases reported from Japan, our patients often showed a progressive loss of B cells and hypogammaglobulinemia. Although patients with CAEBV from Japan have normal or increased numbers of NK cells, many of our patients had reduced NK-cell numbers. Although immunosuppressive agents, rituximab, autologous cytotoxic T cells, or cytotoxic chemotherapy often resulted in short-term remissions, they were not curative. Hematopoietic stem cell transplantation was often curative for CAEBV, even in patients with active lymphoproliferative disease that was unresponsive to chemotherapy. These studies are registered at http://www.clinicaltrials.gov as NCT00032513 for CAEBV, NCT00062868 and NCT00058812 for EBV-specific T-cell studies, and NCT00578539 for the hematopoietic stem cell transplantation protocol.

Clinical evidence of a graft-versus-lymphoma effect against relapsed diffuse large B-cell lymphoma after allogeneic hematopoietic stem-cell transplantation

BACKGROUND A graft-versus-lymphoma effect against diffuse large B-cell lymphoma (DLBCL) is inferred by sustained relapse-free survival after allogeneic stem-cell transplantation; however, there are limited data on a direct graft-versus-lymphoma effect against DLBCL following immunotherapeutic intervention by either withdrawal of immunosuppression or donor lymphocyte infusion (DLI). MATERIALS AND METHODS An analysis was carried out to determine whether a direct graft-versus-lymphoma effect exists against DLBCL. The analysis was restricted to patients with DLBCL, who were either not in complete remission at day +100 after allogeneic stem-cell transplantation or subsequently relapsed beyond this time point. RESULTS Fifteen patients were identified as either not in complete remission (n = 13) at their day +100 evaluation or subsequently relapsed (n = 2) and were assessed for subsequent responses after withdrawal of immunosuppression or DLI. Eleven patients were treated with either withdrawal of immunosuppression (n = 10) or a DLI (n = 1) alone; four patients received chemotherapy with DLI to reduce tumor bulk. Nine (60%) patients subsequently responded (complete = 8, partial = 1). Six responses occurred after withdrawal of immunosuppression alone. Six patients are alive (range 42-83+ months) in complete remission without further treatment. CONCLUSION The demonstration of sustained complete remission following immunotherapeutic intervention provides direct evidence of a graft-versus-lymphoma effect against DLBCL.

Oral Mucositis-Related Oropharyngeal Pain and Correlative Tumor Necrosis Factor-α Expression in Adult Oncology Patients Undergoing Hematopoietic Stem Cell Transplantation

BACKGROUND Oral mucositis is the most common sequela of conditioning chemotherapy (CT) for hematopoietic stem cell transplantation (HSCT) and is the principal cause of most of the associated pain. Tumor necrosis factor-alpha (TNF-alpha) is a key pathogenic component of oral mucositis. OBJECTIVES The primary purpose of this study was to describe oral mucositis-related oropharyngeal pain in the setting of HSCT. A secondary purpose was to assess the effectiveness of molecular biology methods for measuring TNF-alpha concentrations in plasma, saliva, and buccal epithelial cells in patients with oral mucositis undergoing HSCT. METHODS This descriptive, correlative study recruited subjects aged >or= 18 years who were scheduled to receive HSCT with CT. Subjects assessed their pain at baseline and 9 days (+/-24 hours) after CT using a pain visual analog scale (VAS) from 0=no pain to 10=worst possible pain, as well as word descriptors of sensory and affective pain. The extent and severity of oral mucositis were evaluated using the Oral Mucositis Assessment Scale. Saliva and blood samples and buccal brush biopsies were obtained at the same time points. Salivary and plasma TNF-alpha concentrations were measured using an enzyme-linked immunosorbent assay. Quantitative real-time polymerase chain reaction testing was used to measure buccal TNF-alpha gene expression. To determine the optimal method of RNA isolation, samples were extracted using 3 different methods: TRIzol, RNeasy, and RLT/TRIzol. RESULTS Twenty-five adult men and women (mean age, 46 years; age range, 32-68 years; 64% white) underwent HSCT with CT. Significant differences from baseline to day 9 were observed in the severity of oral mucositis (P<0.001), the overall intensity of oral pain (P<0.05), the overall intensity of oral pain with swallowing (P<0.01), the sensory dimension of oral pain with swallowing (P<0.05), and the sensory and affective dimension of oral pain with swallowing (P<0.05). The severity of oral mucositis was significantly associated with the overall intensity of oral pain (P<0.05). Although mean scores for oral pain were low, 8 subjects had clinically unacceptable pain VAS scores (>3) while receiving opioids. Fourteen subjects had measurable increases in buccal TNF-alpha RNA expression at day 9 (P=0.027 vs baseline), as measured using the TRIzol method, which was found to be the best method for measuring this variable. TNF-alpha RNA content in buccal samples was significantly associated with the worst intensity of oral pain with swallowing (partial R(2)=0.19; P<0.05). CONCLUSIONS Despite the use of opioids, oropharyngeal pain remained a treatment challenge in approximately one third of these subjects after CT with HSCT. The sensitive assay used to measure TNF-alpha gene expression in buccal cells may be useful in investigating molecular events in oral mucositis-related pain, as well as in evaluating the therapeutic response to investigational agents.

Phase 2 clinical trial of rapamycin-resistant donor CD4+ Th2/Th1 (T-Rapa) cells after low-intensity allogeneic hematopoietic cell transplantation

In experimental models, ex vivo induced T-cell rapamycin resistance occurred independent of T helper 1 (Th1)/T helper 2 (Th2) differentiation and yielded allogeneic CD4(+) T cells of increased in vivo efficacy that facilitated engraftment and permitted graft-versus-tumor effects while minimizing graft-versus-host disease (GVHD). To translate these findings, we performed a phase 2 multicenter clinical trial of rapamycin-resistant donor CD4(+) Th2/Th1 (T-Rapa) cells after allogeneic-matched sibling donor hematopoietic cell transplantation (HCT) for therapy of refractory hematologic malignancy. T-Rapa cell products, which expressed a balanced Th2/Th1 phenotype, were administered as a preemptive donor lymphocyte infusion at day 14 post-HCT. After T-Rapa cell infusion, mixed donor/host chimerism rapidly converted, and there was preferential immune reconstitution with donor CD4(+) Th2 and Th1 cells relative to regulatory T cells and CD8(+) T cells. The cumulative incidence probability of acute GVHD was 20% and 40% at days 100 and 180 post-HCT, respectively. There was no transplant-related mortality. Eighteen of 40 patients (45%) remain in sustained complete remission (range of follow-up: 42-84 months). These results demonstrate the safety of this low-intensity transplant approach and the feasibility of subsequent randomized studies to compare T-Rapa cell-based therapy with standard transplantation regimens.

Interleukin-7 Immunotherapy

IL-7 is a member of the common gamma-chain family of cytokines sharing a common gamma-chain in their receptor. Beyond its long-established pivotal role in immune development, it has been more recently recognized as a critically important regulator of peripheral naïve and memory T cell homeostasis while its role in postdevelopment thymic function remains at best, poorly defined, and controversial. Its multiple immune-enhancing properties, most notably in the maintenance of T cell homeostasis, make it a very attractive candidate for immunotherapy in a wide variety of clinical situations. Following many years of rich preclinical data in murine and simian models, IL-7 is now emerging in human phase I trials as a very promising immunotherapeutic agent. Human in vivo data discussed here are derived from the phase I study initiated at the National Cancer Institute in collaboration with Cytheris, Inc., in a cohort of subjects with incurable malignancy.

Perspective on Potential Clinical Applications of Recombinant Human Interleukin‐7

Interleukin‐7 has critical and nonredundant roles in T cell development, hematopoiesis, and postdevelopmental immune functions as a prototypic homeostatic cytokine. Based on a large body of preclinical evidence, it may have multiple therapeutic applications in immunodeficiency states, either physiologic (immuno‐senescence), pathologic (HIV) or iatrogenic (postchemotherapy and posthematopoietic stem cell transplant) and may have roles in immune reconstitution or enhancement of immunotherapy. Early clinical development trials in humans show that, within a short time, rhIL‐7 administration results in a marked preferential expansion of both naive and memory CD4 and CD8 T cell pools with a tendency toward enhanced CD8 expansion. As a result, lymphopenic or normal older hosts develop an expanded circulating T cell pool with a profile that resembles that seen earlier in life with increased T cell repertoire diversity. These results, along with a favorable toxicity profile, open a wide perspective of potential future clinical applications.

Quantitative analysis of T cell receptor diversity in clinical samples of human peripheral blood.

The analysis of T cell receptor diversity provides a clinically relevant and sensitive marker of repertoire loss, gain, or skewing. Spectratyping is a broadly utilized technique to measure global TCR diversity by the analysis of the lengths of CDR3 fragments in each Vβ family. However the common use of large numbers of T cells to obtain a global view of TCR Vβ CDR3 diversity has restricted spectratyping analyses when limited T-cell numbers are available in clinical setting, such as following transplant regimens. We here demonstrate that one hundred thousand T cells are sufficient to obtain a robust, highly reproducible measure of the global TCR Vβ repertoire diversity among twenty Vβ families in human peripheral blood. We also show that use of lower cell number results not in a dwindling of observed diversity but rather in non-reproducible patterns in replicate spectratypes. Finally, we report here a simple to use but sensitive method to quantify repertoire divergence in patient samples by comparison to a standard repertoire profile we generated from fifteen normal donors. We provide examples using this method to statistically evaluate the changes in the global TCR Vβ repertoire diversity that may take place during T subset immune reconstitution after hematopoietic stem cell transplantation or after immune modulating therapies.