[Mesenchymal stem cells: a new versatile therapeutic option]

Mesenchymal stem cells (MSC) reside in the stromal compartment of the hematopoietic bone marrow. Although present in small numbers in vivo, MSC may be easily isolated and expanded in cell culture. MSC are able to generate bone, cartilage, fat, and under specific conditions, liver, muscle and nerve. Numerous studies have suggested a potential use of MSC to repair degenerative or traumatic lesions, in organs where tissue repair is limited. Furthermore, MSC are endowed with immunosuppressive properties, utilized to control graft versus host disease and rejection of allogenic hematopoietic stem cell transplants.

Periodontal therapy in siblings with Papillon?Lef�vre syndrome and tinea capitis: a report of two cases

OBJECTIVE

Report of clinical and microbiological periodontal findings before and 6 months after treatment of two siblings with Papillon-Lefèvre syndrome (PLS) and tinea capitis.

METHODS

Two brothers, RG 3 years and NG 5 years of age, were referred for treatment due to premature mobility of their deciduous teeth. Probing depths (PPD), attachment levels (PAL-V), and furcation involvements were examined clinically. Panoramic radiographs were taken. Subgingival plaque samples within the deepest pocket of each tooth were taken and analysed by real-time polymerase chain reaction (PCR) for Actinobacillus actinomycetemcomitans (AA), Porphyromonas gingivalis, Tannerella forsythensis, Treponema denticola, Fusobacterium nucleatum, and Prevotella intermedia. One-stage full-mouth scaling and extraction of hopeless teeth were performed under general anaesthesia, followed by systemic amoxicillin and metronidazole for 7 days. Clinical and microbiological analyses were performed 6 months after treatment.

RESULTS

Before treatment, both siblings had exhibited PPD of up to 13 mm, Class III furcation defects at four teeth, and marginal suppuration. AA was detected in both patients and at all teeth at levels ranging from 3.0 x 10(2) to 5.1 x 10(6). Both patients exhibited palmar and plantar hyperkeratosis. Seven teeth were extracted from RG, and nine from NG. Six months after treatment, PPD had been reduced to <or=5 mm. AA was not detected in any of the remaining teeth.

CONCLUSION

Even periodontally affected deciduous teeth of PLS patients can be treated successfully. Suppression of AA to below detection level seems to be of high significance.

Chimerism and outcomes after allogeneic hematopoietic cell transplantation following nonmyeloablative conditioning

Allogeneic hematopoietic cell transplantation (HCT) following nonmyeloablative conditioning has been extensively evaluated in patients with hematologic malignancies who are ineligible for conventional HCT because of age or medical comorbidities. Nonmyeloablative regimens have led to an initial state of mixed hematopoietic chimerism defined as coexistence of donor- and host-derived hematopoiesis. While nonmyeloablative regimens have been associated with reduced regimen-related toxicities in comparison with conventional myeloablative conditioning, graft rejection, graft-versus-host disease (GVHD), and disease progression have remained significant challenges. In this article, after briefly introducing current techniques for chimerism assessment, we describe factors affecting donor chimerism levels after nonmyeloablative conditioning, and then review data suggesting that chimerism assessment early after HCT might help identify patients at risk for graft rejection, GVHD and relapse/progression. Finally, we discuss how these observations have opened the way to further research protocols evaluating manipulation of postgrafting immunosuppression, and/or infusion of donor immune cells.

Infections after allogeneic hematopoietic stem cell transplantation with a nonmyeloablative conditioning regimen

Hematopoietic cell transplantation (HCT) following nonmyeloablative conditioning (NMSCT) may be associated with a reduced risk of infection compared to standard allogeneic HCT. We retrospectively analyzed incidence and risk factors of infection in 62 patients undergoing NMSCT with low-dose TBI +/- fludarabine and postgrafting CsA and MMF. The proportion of patients with any infection was 77%, but the majority of infectious events occurred beyond day 30. Donor other than sibling, older age, early disease and male gender were significant risk factors. The incidence of bacteremia was 55% at 1 year and the number of bacteremic episodes was 0.9 per patient (0.08 before day 30). The risk of bacteremia increased with older age and the use of a donor other than an HLA-identical sibling, but not with neutropenia. The incidence of infections other than bacteremia correlated with the use of corticosteroids. The risk of CMV infection increased with high-risk CMV serology, and risk of CMV disease with high-risk CMV serology, older age, first transplantation and a diagnosis of lymphoma. In conclusion, after NMSCT, infections are not frequent in the first 30 days post transplant but careful long-term monitoring is necessary thereafter.

Quality of life and clinical correlates in patients with diabetic foot ulcers

OBJECTIVE

To compare the Health Related Quality of Life (HRQL) of French diabetic patients with and without foot ulcers and to determine the factors influencing disease-specific HRQL for those with foot ulcers.

METHODS

355 diabetic patients, including 239 with foot ulcers (group 1) and 116 without foot ulcers (group 2) were studied in a cross-sectional setting. Socio-demographic and clinical variables were recorded and HRQL was evaluated using a generic HRQL questionnaire (SF-36) for all subjects. For group 1, the severity of foot ulcers was assessed according to Wagner's classification, and disease-specific HRQL assessed using the Diabetes Foot Ulcer Scale (DFS).

RESULTS

HRQL was found to be significantly lower (P = 0.0001) in group 1 than in group 2 for all domains of the SF-36. Independent inverse relationships were found between good HRQL in the DFS domain of Leisure and Wagner grade (OR = 0.136 [0.029-0.467]) as well as the number of foot ulcers (OR = 0.365 [0.191-0.678]). Age was significantly associated with several DFS domains including Daily Activities, Physical Health and Dependence.

CONCLUSION

Our findings suggest that the number and severity of foot ulcers are associated with patient HRQL, especially in terms of leisure activity disruption and constraints due to treatment. These findings have implications for the evaluation, planning and management of patient care in diabetic foot disease.

[Nonmyeloablative stem cell transplantation as cancer immunotherapy]

Allogeneic hematopoietic stem cell transplantation (HSCT) is used for the treatment of selected haematological malignancies. Its curative potential is based on two different mechanisms, i.e. the conditioning regimen and the graft-versus-host immunologic reactions. However, because of its toxicity, it is restricted to younger and fitter patients. These observations led several groups to set up new (less toxic) transplant protocols. These transplants are called nonmyeloablative HSCT or minitransplants. These are feasible with a relatively low transplant-related mortality even in patients up to 70 years. In addition, strong anti-tumor responses are observed in several haematological malignancies.

High doses of transplanted CD34+ cells are associated with rapid T-cell engraftment and lessened risk of graft rejection, but not more graft-versus-host disease after nonmyeloablative conditioning and unrelated hematopoietic cell transplantation

This report examines the impact of graft composition on outcomes in 130 patients with hematological malignancies given unrelated donor granulocyte-colony-stimulating-factor-mobilized peripheral blood mononuclear cells (G-PBMC) (n = 116) or marrow (n = 14) transplantation after nonmyeloablative conditioning with 90 mg/m(2) fludarabine and 2 Gy TBI. The median number of CD34(+) cells transplanted was 6.5 x 10(6)/kg. Higher numbers of grafted CD14(+) (P = 0.0008), CD3(+) (P = 0.0007), CD4(+) (P = 0.001), CD8(+) (P = 0.004), CD3(-)CD56(+) (P = 0.003), and CD34(+) (P = 0.0001) cells were associated with higher levels of day 28 donor T-cell chimerism. Higher numbers of CD14(+) (P = 0.01) and CD34(+) (P = 0.0003) cells were associated with rapid achievement of complete donor T-cell chimerism, while high numbers of CD8(+) (P = 0.005) and CD34(+) (P = 0.01) cells were associated with low probabilities of graft rejection. When analyses were restricted to G-PBMC recipients, higher numbers of grafted CD34(+) cells were associated with higher levels of day 28 donor T-cell chimerism (P = 0.01), rapid achievement of complete donor T-cell chimerism (P = 0.02), and a trend for lower risk for graft rejection (P = 0.14). There were no associations between any cell subsets and acute or chronic GVHD nor relapse/progression. These data suggest more rapid engraftment of donor T cells and reduced rejection rates could be achieved by increasing the doses of CD34(+) cells in unrelated grafts administered after nonmyeloablative conditioning.

Low T-cell chimerism is not followed by graft rejection after nonmyeloablative stem cell transplantation (NMSCT) with CD34-selected PBSC

We investigate the feasibility of CD34-selected peripheral blood stem cell (PBSC) transplantation followed by pre-emptive CD8-depleted donor lymphocyte infusions (DLI) after a minimal conditioning regimen. Six patients with advanced hematological malignancies ineligible for a conventional myeloablative transplant (n=5) or metastatic renal cell carcinoma (n=1), and with an HLA-identical (n=4) or alternative (n=2) donor were included. The nonmyeloablative conditioning regimen consisted in 2 Gy TBI alone (n=4), 2 Gy TBI and fludarabine (RCC patient, n=1) or cyclophosphamide and fludarabine (patient who had previously received 12 Gy TBI, n=1). Post transplant immunosuppression was carried out with cyclosporin (CyA) and mycophenolate mofetil (MMF). Initial engraftment was achieved in all patients. One out of six patients (17%) experienced grade > or =2 acute GVHD only after abrupt cyclosporin discontinuation and alpha interferon therapy for life-threatening tumor progression. T-cell chimerism was 23% (19-30) on day 28, 32% (10-35) on day 100, 78% (49-95) on day 180 and 99.5% (99-100) on day 365. Three out of four patients who had measurable disease before the transplant experienced a complete response. We conclude that CD34-selected NMSCT followed by CD8-depleted DLI is feasible and preserves engraftment and apparently also the graft-versus-leukemia (GVL) effect. Further studies are needed to confirm this encouraging preliminary report.

Preemptive cellular immunotherapy after T-cell-depleted allogeneic hematopoietic stem cell transplantation

GVHD is a life-threatening complication of allogeneic hematopoietic stem cell transplantation (HSCT). GVHD is due to donor lymphocytes that are cotransplanted with donor stem cells. These donor lymphocytes are primed by histocompatibility differences between donors and recipients and activated by a cytokine storm caused by the conditioning regimen. The most efficient method for prevention of GVHD consists of T-cell depletion (TCD) of the graft. However, TCD usually leads to an increased risk of leukemia relapse because of the loss of the graft-versus-leukemia (GVL) effect. Several groups have studied the feasibility of preemptive donor lymphocyte infusion (DLI) to lessen the impact of TCD on leukemia relapse. Preemptive DLI is given several weeks to months after the transplantation, ie, after the cytokine storm and after the patient has recovered from conditioning-regimen-related toxicities. After briefly discussing various techniques of TCD of the graft and the efficacy of DLI, this article reviews the first clinical studies evaluating a strategy of TCD of the graft followed by preemptive DLI.

An economic evaluation of the cost of diabetic foot ulcers: results of a retrospective study on 239 patients

OBJECTIVE

To evaluate the cost of foot ulcers in diabetic patients.

METHODS

Retrospective pharmacoeconomic study using direct and indirect costs (sick leave days) from the perspective of French social security system.

RESULTS

239 patients were included in the study by 80 physicians who treat diabetic patients suffering from foot ulcers. Initially identified by telephone survey, these physicians were primarily endocrinologists/diabetologists, general practitioners and surgeons. Average monthly costs in the treatment of foot ulcers were 697 euro; for outpatient care, 1556.20 euro; for hospital care (day treatment and short stays), and 34.76 euro; for sick leaves. When hospitalization was required, it represented approximately 70% of the average cost for foot ulcers. The portion of outpatient costs was principally generated by medical and paramedical treatments, and interventions carried out by healthcare personnel. On the other hand, medication only represented 10% of total costs. The initial severity of the pathology was a determinant clinical factor of high healthcare costs. In addition, the more recent the lesion was, the higher the cost of treatment. Amputation and follow-up by specialists were correlated to high costs as well, a logical result of these clinical factors.

CONCLUSION

This analysis is the first to evaluate the cost of treating foot ulcers in such a large population of diabetic patients. The economic outcomes should help direct public authorities in their choices, particularly as regards the interest of treating these diabetes-related complications as early as possible.

[How I treat...chronic myeloid leukemia]

This review article describes the identification of the tyrosine kinase BCR/ABL as the hallmark of chronic myeloid leukemias (CML) as well as the development of a specific inhibitor of this tyrosine kinase, the STI571 (Glivec, imatinib mesylate). The authors discuss the results of a phase I and three phase II trials reporting the efficacy of STI571 as treatment for CML patients and propose two simplified algorithms that may help to guide decision-making for the individual patient.

Minitransplants: allogeneic stem cell transplantation with reduced toxicity

Allogeneic hematopoietic stem cell transplantation (HSCT) is used for the treatment of selected hematological malignancies. Its curative potential is based on two very different mechanisms, involving the conditioning regimen and the graft-versus-host reactions, respectively. The high-dose chemo-radiotherapy conditioning regimen is aimed at destroying tumor cells, ablating the host immune system (to prevent rejection) and eliminating the host bone marrow (to "make space" for donor stem cells). However, the definitive eradication of tumor cells is also largely mediated by an immune-mediated destruction of malignant cells by donor lymphocytes termed graft-versus-leukemia (GVL) or graft-versus-tumor (GVT) effect. However, because of its toxicity, conventional allogeneic HSCT is restricted to younger (< 55 years) and fitter patients. These observations led several groups to set up new (less toxic) transplant protocols based on a two step approach: first the use of immunosuppressive (but nonmyeloablative) conditioning regimens providing sufficient immunosuppression to achieve engraftment of allogeneic hematopoietic stem cells and, in a second step, destruction of malignant cells by the GVL effect. These transplants are called nonmyeloablative HSCT or reduced-conditioning HSCT or minitransplants. Preliminary results show that minitransplants are feasible with a relatively low transplant-related mortality (TRM) even in patients up to 70 years. In addition, strong anti-tumor responses are observed in several hematological malignancies as well as in some patients with renal cell carcinoma. As the benefits of minitransplants over alternative forms of treatment remain to be demonstrated, this strategy should be restricted to patients included in clinical trials.

Erythropoiesis after nonmyeloablative stem-cell transplantation is not impaired by inadequate erythropoietin production as observed after conventional allogeneic transplantation

BACKGROUND

It is now well established that after conventional allogeneic hematopoietic stem-cell transplantation (HSCT), erythropoietic recovery is impaired because erythropoietin (Epo) production remains inadequate for prolonged periods of time. However, erythropoietic reconstitution after nonmyeloablative SCT (NMSCT) has never been characterized.

METHODS

Twelve patients received a nonmyeloablative conditioning regimen consisting of 2 Gy total body irradiation (TBI) alone (n=6), 2 Gy TBI and fludarabine (n=3), or cyclophosphamide and fludarabine (n=3), followed by transplantation of allogeneic peripheral blood stem cells. Graft-versus-host-disease (GvHD) prophylaxis was carried out with mycophenolate mofetil (from day -1 to day 28) plus cyclosporine (from day -1 to day 120 or longer in case of chronic GvHD). Erythropoiesis was quantitated by soluble transferrin receptor (sTfR) levels, and the adequacy of Epo production was evaluated by the observed-to-predicted Epo ratio (O/P Epo).

RESULTS

Mean sTfR levels decreased following the conditioning regimen but remained well within the normal range throughout the posttransplant period. The O/P Epo ratio presented an initial surge quite similar to that observed after conventional conditioning. Thereafter, the O/P Epo ratio normalized rapidly, and Epo levels remained adequate during the whole observation period.

CONCLUSION

Contrarily to what is observed after myeloablative transplant, Epo levels remained adequate after NMSCT, resulting in normal erythropoiesis. These results suggest that the administration of erythropoietin therapy (rHuEpo) could be less effective after NMSCT than after conventional allogeneic transplant.

Nonmyeloablative allogeneic hematopoietic stem cell transplantation

Allogeneic hematopoietic stem cell transplantation (HSCT) is the most effective treatment for selected hematological malignancies. Its curative potential is largely mediated by an immune-mediated destruction of malignant cells by donor lymphocytes termed graft-versus-leukemia (GVL) effect. However, because of its toxicity, conventional allogeneic HSCT is restricted to younger and fitter patients. These observations led several groups to set up new (less toxic) transplant protocols (nonmyeloablative stem cell transplantation or NMSCT) based on a two-step approach: first, the use of immunosuppressive (but nonmyeloablative) preparative regimens providing sufficient immunosuppression to achieve engraftment of allogeneic hematopoietic stem cells and, in a second step, destruction of malignant cells by the GVL effect. Preliminary results showed that NMSCT were feasible with a relatively low transplant-related mortality (TRM), even in patients older than 65 years. In addition, strong antitumor responses were observed in several hematological malignancies as well as in some patients with renal cell carcinoma. After discussing the mechanisms and efficacy of the GVL effect as well as the rationale for NMSCT strategies, this article reviews the first results of ongoing clinical trials. Innovative modalities that may permit amplification of the GVL effect while minimizing the risk of GVHD are discussed. Because the benefits of NMSCT over alternative forms of treatment remain to be demonstrated, this strategy should be restricted to patients included in clinical trials.