Biomedical subjects

P Comoli

Publications and source records attributed to P Comoli.

At least 19 recordsLinked to original sources

PubMed2004

Adoptive transfer of allogeneic Epstein-Barr virus (EBV)-specific cytotoxic T cells with in vitro antitumor activity boosts LMP2-specific immune response in a patient with EBV-related nasopharyngeal carcinoma.

BACKGROUND: The outcome of patients with nasopharyngeal carcinoma (NPC) presenting as advanced-stage disease or failing conventional radio-chemotherapy is poor. Thus, additional forms of effective, low-toxicity treatment are warranted to improve NPC prognosis. Since NPC is almost universally associated with Epstein-Barr virus (EBV), cellular immunotherapy with EBV-specific cytotoxic T lymphocytes (CTLs) may prove a successful treatment strategy. Patient and methods A patient with relapsed NPC, refractory to conventional treatments, received salvage adoptive immunotherapy with EBV-specific CTLs reactivated ex vivo from a human leukocyte antigen-identical sibling. EBV-specific immunity, as well as T-cell repertoire in the tumor, before and after immunotherapy, was evaluated. RESULTS: CTL transfer was well tolerated, and a temporary stabilization of disease was obtained. Moreover, notwithstanding the short in-vivo duration of allogeneic CTLs, immunotherapy induced a marked increase of endogenous tumor-infiltrating CD8+ T lymphocytes, and a long-term increase of latent membrane protein 2-specific immunity. CONCLUSIONS: Preliminary data obtained in this patient indicate that EBV-specific CTLs are safe, may exert specific killing of NPC tumor cells in vitro, and induce antitumor effect in vivo.

Adult↗

PubMed2003

Polyomavirus BK infection in pediatric kidney-allograft recipients: a single-center analysis of incidence, risk factors, and novel therapeutic approaches.

BACKGROUND: Although a growing body of literature regarding polyoma BK virus (BKV) infection and associated interstitial nephritis in kidney-allograft recipients is becoming available, the impact of BKV infection in the pediatric population has not been fully evaluated. METHODS: In a retrospective analysis, we performed polymerase chain reaction (PCR) assays for BKV DNA in serum and urine samples from 100 pediatric kidney-allograft recipients referred to our institution in the last 5 years. RESULTS: BKV viruria was observed in 26 of 100 patients, whereas BKV viremia was demonstrated in 5 patients. Serum creatinine was significantly higher in recipients with positive BK viremia compared with BKV DNA-negative patients (mean 2.66 vs. 1.14 mg/100 mL). Renal biopsy performed in 3 of 5 patients showed graft damage consistent with interstitial nephropathy. In the univariate analysis, negative antibody status of the recipient and the presence of mycophenolate mofetil in baseline immunosuppression were the two factors predictive of active BKV infection. CONCLUSIONS: Our study shows that BKV-associated nephropathy is a relevant complication in the pediatric kidney transplantation setting also. Identification of patients at risk of developing virus-associated nephropathy, through prospective quantification of viral load, could improve clinical outcome by allowing the use of timely preemptive therapy guided by BKV DNA levels.

Adolescent↗

PubMed2003

Successful T-cell-depleted, related haploidentical peripheral blood stem cell transplantation in a patient with Fanconi anaemia using a fludarabine-based preparative regimen without radiation.

Haematopoietic stem cell transplantation (HSCT) represents the treatment of choice for severe bone marrow failure in patients with Fanconi anaemia (FA). When the donor is a compatible relative, the chance of being cured with an allograft is in the order of 70%. However, for FA children lacking an HLA-identical sibling, the results of HSCT from an alternative donor are less satisfactory because of a higher risk of graft rejection, graft-versus-host-disease (GVHD) and regimen-related toxicity. We report on a 12-year-old girl with FA, who was treated by T-cell-depleted (TCD) peripheral blood HSCT from her haploidentical uncle, using a novel fludarabine-based preparative regimen without radiation. She had rapid engraftment with no toxicity and no GVHD. Progressive recovery of both numbers of lymphocyte and of proliferative response to polyclonal activators occurred over time. At 18 months after transplantation, she is well with 100% donor chimerism and has recovered normal immune function.

Child↗

PubMed2001

Ex vivo priming for long-term maintenance of antileukemia human cytotoxic T cells suggests a general procedure for adoptive immunotherapy.

Adoptive cellular immunotherapy has proven to be a successful approach in preventing and curing cytomegalovirus infection and Epstein-Barr virus-associated lymphomas after bone marrow transplantation. Translation of this approach for preventing leukemia relapse after bone marrow transplantation might require ex vivo priming and long-term maintenance of leukemia blast-specific T cells. To accomplish this goal, procedures were optimized for the in vitro priming of naive CD8 using dendritic cells activated by CD40 ligation, interleukin-12 (IL-12), and IL-7. Using T lymphocytes and dendritic cells obtained from HLA-matched allogeneic bone marrow transplantation donors and leukemia blasts as a source of tumor antigens, anti-acute myeloid leukemia cytotoxic T lymphocytes (CTLs) were induced. In these experiments, it was found that though it is possible to induce CTLs using immature dendritic cells, IL-12, and IL-7, obtaining long-term CTLs requires the presence of CD4 T cells in the priming phase. Using this approach, long-term antileukemia CTL lines could be generated from 4 of 4 bone marrow donors. Because this procedure does not require definition of the target antigen and because it selects responding cells from a virgin T-cell repertoire, its general application is suggested in adoptive immunotherapy and in the definition of tumor rejection antigens.

Bone Marrow Transplantation↗

PubMed2001

Correction of DiGeorge anomaly with EBV-induced lymphoma by transplantation of organ-cultured thymus and Epstein-Barr-specific cytotoxic T lymphocytes.

A young woman with DiGeorge anomaly showed normal immune tests as a child and did not experience the symptoms of profound T cell immunodeficiency. However, she had chronic pulmonary infections which led to bronchiectasis. At age 14, she developed an Epstein-Barr virus-induced lymphoma and her T cell function tests were markedly abnormal. After intensive chemotherapy, she received an organ-cultured thymus transplant but because of an abnormally high EBV DNA titer was also given autologous EBV-specific cytotoxic T cells, prepared prior to transplant. Titers fell from 80,000 genome copies/mg DNA to 2000 within 6 weeks. She was clinically well and her T cell tests improved. Sixteen months after the transplant, however, her tumor returned; EBV DNA levels had risen to 40,000 copies/mg DNA. She again received autologous EBV-specific cytotoxic T lymphocytes and valcyclovir and Cytogam as well. Her tumor resolved on this therapy and she has remained well to this date, 29 months after the recurrence. T cell tests, which had deteriorated with the recurrence of the tumor, now show normal responses. This experience records a number of unique features of thymus transplantation. This is the first recorded successful thymus transplant in a patient with partial T cell immunity and thus expands the potential of this treatment modality to patients other than infants with complete DiGeorge anomaly. The patient demonstrates cytotoxic activity against mouse cells, demonstrating the ability to respond to a new antigen which requires host antigen presenting cells. Measurement of alpha 1 TRECs (T cell receptor excision circles) shows evidence of increasing and sustained thymopoiesis since the transplant at a level consistent with the age of the transplant donor rather than that of the recipient.

Biopsy↗

PubMed2001

Analysis of immune reconstitution in children undergoing cord blood transplantation.

OBJECTIVE: The aim of this study was to investigate and compare immune reconstitution in allogeneic cord blood transplantation (CBT) and bone marrow transplantation (BMT) recipients. MATERIALS AND METHODS: Twenty-three children underwent CBT from either human leukocyte antigen-identical siblings (11 cases) or unrelated donors (12 cases) were enrolled in the study, together with 23 matched children receiving BMT. Patients were analyzed 2-3 and 12-15 months after transplant. Recovery of T-, B-, and NK-lymphocyte subsets, proliferative in vitro response to mitogens, as well as cytotoxic activities, were investigated. RESULTS: CBT recipients showed a marked increase in the number of B lymphocytes as compared with patients who underwent BMT (p < 0.001). The absolute number of CD3(+) and CD8(+) T cells, as well as the proliferative response to T-cell mitogens, recovered with time after transplantation, irrespective of the source of stem cells used. Recipients of unrelated CBT had a better recovery of CD4(+) T lymphocytes (p < 0.01). Among patients experiencing acute graft-versus-host disease (GVHD), children given CBT had a much greater production of CD4(+) CD45RA(+) T cells than BMT recipients (p < 0.005). Recovery of NK cell number and innate cytotoxic activities was fast, irrespective of the source of stem cells used. CONCLUSIONS: Despite the much lower number of lymphocytes transferred with the graft, recovery of lymphocyte number and function toward normal in CBT recipients was rapid and comparable to that observed after transplantation of bone marrow progenitors. This prompt immune recovery possibly was favored by the reduced incidence and severity of GVHD observed in children who underwent CBT.

Acute Disease↗

PubMed2001

Human alloantigen-specific anergic cells induced by a combination of CTLA4-Ig and CsA maintain anti-leukemia and anti-viral cytotoxic responses.

The success of allogeneic hematopoietic stem cell transplantation from HLA-disparate donors depends on the development of new strategies for graft-versus-host disease prevention able to target specifically donor antihost alloreactivity, while preserving GVL and antiviral immune surveillance. Recent experimental and clinical work has shown the feasibility of an approach based on induction of anergy to host alloantigens through blockade of B7/CD28 costimulatory signal in donor T cells, but data on the impact of this strategy on the recovery of the immune system are still lacking. We devised an ex vivo method for induction of host alloantigen-specific unresponsiveness based on treatment with the B7/CD28 blocking agent CTLA4-Ig associated with CsA. We then proceeded to assess the maintenance of an effective immune response towards viral pathogens and tumor cells after CTLA4-Ig/CsA treatment, by measuring the frequency of CTL precursors directed against CMV- and EBV-infected targets, and against autologous leukemic blasts. We demonstrated that (1) CTLA4-Ig and CsA can act synergistically in inducing a state of unresponsiveness to alloantigens; (2) the number of leukemia-reactive, EBV-specific and CMV-specific CTLp is not impaired by CTLA4-Ig/CsA treatment. Our data provide the first direct in vitro evidence that it is possible to preserve antiviral and antileukemia effector cells after blockade of CD28/B7 interaction during MLR.

Abatacept↗

PubMed2001

Infections after stem cell transplantation in children: state of the art and recommendations.

At the workshop on infections after stem cell transplantation (SCT) in children, the following topics were introduced by invited speakers and discussed with the audience: empirical antimicrobial therapy in the pre-engraftment period, early diagnosis of fungal and viral infections and possibilities to treat them and the possible role of G-CSF early post-SCT. Episodes of fever in the pre-engraftment period mostly are unexplained, and in about one quarter due to bacteremia, mostly by Gram-positive cocci. No single drug or combination of drugs used for antimicrobial therapy is superior, neither does it cover 100% of the pathogens. Close microbiological surveillance of the patients and knowledge of the local microbial epidemiology are requested for optimal therapy. Early fungal infections are reactivations of pre-SCT infections, late fungal infections mostly are associated with failure of engraftment or GvHD and its treatment. Except for suggestive ultrasound or CT-scan abnormalities, the possibilities for early diagnosis are limited c.q. not reliable. Fluconazol prophylaxis is recommended to prevent Candida albicans invasion. A number of new antifungal drugs are being tested in phase I and II studies. CMV, EBV and adenoviruses may reactivate after SCT, causing severe disease with a high mortality, especially in non-HLA-identical donor-recipient combinations. Frequent surveillance cultures for CMV and adenoviruses, pp65-CMV antigen detection in WBC and PCR techniques for CMV, EBV and adenoviruses all have their own contribution to the early diagnosis of dissemination of the viral infection. Therapeutical possibilities, except with respect to ganciclovir and foscarnet for CMV infection, are still limited. The effectiveness of cidofovir is under study. Adoptive therapy with virus-specific CTL's probably represents the new frontier. G-CSF administration early after SCT has a beneficial effect on PMN recovery, hospitalization time, use of antibiotics and total parenteral nutrition requirement in children undergoing allogeneic and autologous BMT. No benefit is observed in children undergoing peripheral blood SCT. The routine use of G-CSF in the latter group of patients is not justified.

Anti-Bacterial Agents↗

PubMed2000

High levels of Epstein-Barr virus DNA in blood of solid-organ transplant recipients and their value in predicting posttransplant lymphoproliferative disorders.

Epstein-Barr virus (EBV) DNA was quantitated in peripheral blood mononuclear cells (PBMC) from 25 healthy subjects, 105 asymptomatic solid-organ transplant (SOT) recipients, and 15 SOT recipients with symptomatic EBV infections by using a newly developed quantitative-PCR technique. Patients with symptomatic EBV infections had significantly higher (P < 0.001) median EBV DNA levels than asymptomatic SOT recipients and immunocompetent individuals. In SOT recipients, the positive predictive value of EBV DNA levels of >1, 000 genome equivalents (GE)/0.5 microg of total PBMC DNA was 64.7% for symptomatic EBV infection, while the negative predictive value was 96.1%. In 19 of 32 (59.3%) asymptomatic SOT recipients, EBV DNA levels were consistently below 1,000 GE for as long as 18 months, while 10 of 32 (31.2%) patients had 1,000 to 5,000 EBV GE at least once during follow-up. In a minority of patients (3 of 32; 9.3%), >/=5,000 GE could be detected at least once during follow-up. Reduction of immunosuppressive treatment decreased EBV DNA levels by >/=1 log(10) unit in patients with symptomatic EBV infections. Quantification of EBV DNA is valuable for the diagnosis and monitoring of symptomatic EBV infections in SOT recipients.

Adolescent↗

PubMed1999

Depletion of alloreactive T cells by a specific anti-interleukin-2 receptor p55 chain immunotoxin does not impair in vitro antileukemia and antiviral activity.

The success of bone marrow transplantation (BMT) from HLA-disparate donors depends on the development of new strategies able, on one hand, to efficiently prevent graft-versus-host disease (GVHD) and, on the other hand, to protect leukemic patients from relapse and infections. Using an immunotoxin (IT) directed against the alpha chain (p55) of the human interleukin-2 receptor (RFT5-SMPT-dgA), we previously showed that it is possible to kill mature T cells activated against a specific HLA complex by a one-way mixed lymphocyte culture (MLC). The present study was performed to investigate whether this protocol of allodepletion affects the capacity of residual T cells to display antileukemia and antiviral activity evaluated by limiting dilution assays (LDA), measuring the frequency of cytotoxic T-lymphocyte precursors (CTLp) directed against autologous leukemic blasts (LB) and cytomegalovirus (CMV)- and Epstein-Barr virus (EBV)-infected target cells. Antileukemia activity was evaluated in peripheral blood mononuclear cells (PBMC) of 3 patients treated for acute myeloid leukemia who had developed a high frequency of LB-reactive CTLp after either autologous or allogeneic BMT. Results demonstrate that (1) depletion with RFT5-SMPT-dgA efficiently inhibited MLC; (2) fresh PBMC of patients yielded a high frequency of LB-reactive CTLp comparable to that of the mock-treated PBMC; and (3) effector cells obtained after allodepletion fully retained the capacity to lyse pretransplant LB. By contrast, the frequency of CTLp directed against patient's pretransplant BM remission cells was always undetectable. Data obtained in 4 healthy donors showed that specifically allodepleted T cells recognized and killed autologous CMV-infected fibroblasts and autologous EBV-B-lymphoblastoid cell lines. In conclusion, our data indicate that allodepletion using RFT5-SMPT-dgA efficiently removed alloreactive cells, while sparing in vitro antileukemic and antiviral cytotoxic responses.

Bone Marrow Cells↗

PubMed1999

Characterisation of CTL directed towards non-inherited maternal alloantigens in human cord blood.

Allogeneic cord blood transplantation (CBT), especially from unrelated donors, is being increasingly used for treating paediatric patients with both malignant and non-malignant disorders. Recent clinical and experimental evidence suggests that human cord blood mononuclear cells (CBMC) may acquire in utero a state of tolerance towards non-inherited maternal antigens (NIMA). In order to better define this phenomenon, we measured, by means of a limiting dilution assay (LDA), the frequency of NIMA-specific CTL precursors (CTLp) in cord blood samples obtained from 13 healthy neonates. The immunophenotype of the effector cells recovered from LDA was also analysed. Data concerning both CTLp frequency and phenotype of effector cells were compared with those obtained stimulating CBMC with cells of paternal origin (NIPA) and adult PBMC with allogeneic targets. Results showed that cytotoxic cells directed towards cells of maternal origin could be detected in all cord blood samples tested. Phenotype analysis demonstrated that NIPA elicit the expansion of CD3+/CD8bright T cells, a phenotype associated with alloreactive CTL. By contrast, NIMA preferentially stimulated the expansion of CD3-/CD8dim+ cells, a phenotype associated with NK cells, which are known to be able, in certain clinical conditions, to kill allogeneic haematopoietic cells without causing GVHD. Thus, our results indicate that, when evaluated in a limiting dilution condition, NIMA-reactive cord blood cells are detectable and a preferential expansion of NK cells is observed.

Adult↗

PubMed1998

Immunization with Haemophilus influenzae type b conjugate vaccine in children given bone marrow transplantation: comparison with healthy age-matched controls.

Forty-seven patients (age range, 7 months-18 years) with malignant (38 cases) and nonmalignant (9 cases) disorders given an allogeneic or an autologous bone marrow transplantation (BMT) were immunized with Haemophilus influenzae type b (Hib) polysaccharide-diphtheria toxoid conjugate vaccine administered in a single dose at different time points after transplantation. Results were compared with those of 13 healthy children matched for age and sex who received the same immunization schedule. Serum and saliva samples for measurement of total IgG subclass and specific antibody levels were obtained from patients and healthy controls before and 3 weeks after vaccination. Twenty-five of the 47 patients (53%) had a specific anti-Hib IgG response, while an effective IgA and IgM response was mounted by 23 (49%) and 11 (23%) children, respectively. In the control group, 13 of 13 subjects mounted a specific IgG antibody production (P < 0.005 in comparison to the patients' response rate), while an IgA and IgM response was demonstrated in 12 (92%; P < 0.01 compared to transplanted patients) and 7 (54%; P < 0.05 in comparison to BMT recipients) children, respectively. Lapse of time from BMT to immunization was the most important factor predicting antibody response, as proved by an effective increase in prevaccination specific IgG levels in the majority of patients vaccinated after 2 years from transplant. Our data demonstrate that BMT recipients have a reduced capacity to mount an antibody response to polysaccharide antigens compared to normal controls, even when a protein-conjugated vaccine is employed. Since time after transplant is the major factor influencing the recovery of immune reactivity to polysaccharide antigens, the ontogeny of the B cell repertoire seems to follow a predetermined sequential program of development.

Adolescent↗

PubMed1998

Does the emergence and persistence of donor-derived leukaemia-reactive cytotoxic T lymphocytes protect patients given an allogeneic BMT from recurrence? Results of a preliminary study.

The frequency of CTL precursors (CTLp) directed towards recipient-derived pre-transplant leukaemic blasts (LB) was measured in the peripheral blood of nine children with acute leukaemia and given BMT from either an HLA-identical sibling or a matched unrelated donor (MUD). Patients were evaluated at various time points between 1 month and more than 2 years after transplantation. A high frequency of donor-derived LB-reactive CTLp was detectable 2-6 months after BMT in all children and persisted for at least up to 18 months in the eight patients in haematological remission, while it rapidly declined in the only patient who relapsed. Generation of LB-reactive T cell clones obtained from some of these patients demonstrates that various T lymphocyte subsets, either HLA class I-restricted/TCR-dependent or HLA-unrestricted, contribute to this phenomenon. The in vitro GVL effect here described seems to be at least partially separated from GVHR, since no correlation was observed between the emergence of LB-reactive CTLp and the development and/or severity of GVHD. Development of LB-reactive CTL in the patients was independent of the frequency of these cells in the donor. These data suggest that donor-derived CTL activity specifically directed towards leukaemic blasts may develop in patients given allogeneic BMT and contribute to the maintenance of a state of haematological remission.

Bone Marrow Transplantation↗

PubMed1998

Allogeneic transplantation of haematopoietic progenitors for myelodysplastic syndromes and myeloproliferative disorders.

Since children with myelodysplastic syndromes (MDS) and myeloproliferative disorders (MPD) have a poor prognosis and conventional chemotherapy did not prove to be effective in eradicating them, paediatric patients affected by these diseases and with an HLA-histocompatible donor are to be considered elective candidates for allogeneic transplantation of haematopoietic stem cells (HSC). For those patients with a compatible sibling relapse remains the most important problem, whereas in children transplanted from alternative donors graft rejection and transplant-related mortality significantly contribute to treatment failure. A detailed analysis on the different patient, disease and treatment factors correlated with transplant outcome in childhood MDS and MPD is discussed.

Child↗

PubMed1998

Cord blood transplantation for children with acute leukemia. Eurocord Transplant Group.

Over the past decade, allogeneic cord blood transplantation (CBT) has been widely used for treating patients with malignant disorders. However, the reported low incidence of GVHD observed after allogeneic CBT might be a major drawback in leukemic recipients and at present it is not clear whether CBT really predisposes patients to an increased risk of leukemia relapse. In order to further elucidate the role of CBT in children with hematological malignancies, 54 patients with ALL or AML given either a related (31 cases) or an unrelated (23 cases) CBT in 25 centers participating in the Eurocord Registry were analyzed. Overall survival of related and unrelated CBT recipients was substantially similar, the most important factor influencing patients' outcome being disease state at time of transplantation. In fact, due to a markedly increased relapse rate, poor-risk children (ie patients transplanted in more advanced disease) experienced a significantly worse EFS than those given CBT in a more favorable disease phase (ie CR1 or CR2). These data confirm that allogeneic CBT from either a related or an unrelated donor is a feasible procedure able to cure a significant proportion of children with acute leukemia, especially if transplanted in a favorable phase of disease.

Acute Disease↗

PubMed1997

Transplantation of cord blood progenitor cells can promote bone resorption in autosomal recessive osteopetrosis.

Allogeneic BMT has been reported to be the only curative therapy for children with juvenile autosomal recessive osteopetrosis. We report the case of a 14-month-old child in whom bone resorption was observed after cord blood transplantation (CBT). The patient was given CBT from an unrelated newborn matched for five of six HLA antigens. At the time of transplantation, the child presented with neurological symptoms, with feeding problems and visual impairment. A successful engraftment of donor hematopoiesis was demonstrated and the child experienced grade I acute GVHD. Progressive bone clearing was achieved and a bone marrow trephine demonstrated signs of osteoclast function. Despite full engraftment and bone resorption, neurologic deterioration did not improve. This experience documents that CBT can promote the correction of juvenile osteopetrosis. The shorter time needed both to identify an unrelated donor and to perform the transplant, as well as the lower incidence of GVHD make this procedure more appealing than BMT in children lacking an HLA-compatible relative.

Bone Resorption↗

PubMed1997

Infusion of donor-derived peripheral blood leukocytes after transplantation of cord blood progenitor cells can increase the graft-versus-leukaemia effect.

We describe the case of a child affected by acute lymphoblastic leukaemia who received adoptive immunotherapy after cord blood transplantation (CBT). The patient, transplanted in second relapse resistant to chemotherapy, still showed lung and costal leukaemic nodular lesions 2 months after CBT. For this reason, three infusions of donor peripheral blood leukocytes 1 x 10(7)/kg each were administered on days +60, +80 and +100. The procedure was well tolerated by both patient and donor, and a complete disappearance of the lung lesions was documented 2 months after the last infusion. The patient remains in continuous complete haematological remission 13 months after CBT. This experience suggests that adoptive immunotherapy may be safely employed after CBT in order to increase the contribution of immune-mediated anti-leukaemia effect.

Adoptive Transfer↗

PubMed1997

High frequency of Epstein-Barr virus (EBV) lymphoblastoid cell line-reactive lymphocytes in cord blood: evaluation of cytolytic activity and IL-2 production.

We investigated natural immunity towards autologous EBV lymphoblastoid cell lines (EBV-LCL) in the cord blood. Cord blood lymphocytes (CBL) from 20 healthy neonates were examined together with three EBV+ and one EBV- adult donors. We found that high frequencies of EBV-LCL-reactive cytotoxic lymphocytes, ranging from 1/190 to 1/12,205 were detectable in EBV- and EBV+ donors, as well as in the cord blood of 15 out of 20 neonates. Surface phenotype analysis, depletion experiments with MoAbs specific for T and natural killer (NK) lymphocyte subsets, and T lymphocyte cloning procedures strongly indicate virus-specific cytotoxic T lymphocytes (CTL) as the major population responsible for the lysis of autologous EBV-LCL in EBV+ donors. Conversely, a high frequency of NK cells seems to be involved in the killing activity observed in neonates and in the EBV- donor. Frequencies of EBV-LCL-induced IL-2-producing lymphocytes were high in EBV+ donors (range 1/2247-1/6633) and heterogeneous, but consistent, in cord blood (range 1/5072-1/57,819) and in the EBV- adult (1/17,148). CD8+ lymphocytes were responsible for IL-2 production in EBV+ individuals, while CD4+ T cells were charged with this role in cord blood and in the EBV- donor. These data demonstrate that CBL are able to develop a strong innate immunity, directed against autologous EBV-infected cells, mediated by both NK cells and CD4+ T lymphocytes. This characteristic may be relevant for protection against viral infections in both neonates and patients given cord blood transplantation (CBT).

Adult↗