ALBERT

Description: The combination of fludarabine, cyclophosphamide and rituximab (FCR) is still currently regarded as the standard regimen for treatment of physically fit patients with chronic lymphocytic leukemia (CLL). This therapy can be associated with significant toxicity, and patient adherence to the protocol may often be difficult outside of clinical trials. This retrospective study aimed to evaluate the efficacy and safety of FCR therapy in the real life setting, with particular focus on the influence of dose reduction on treatment outcome. A total of 132 CLL patients (≤70 years of age) treated with FCR as frontline therapy from 10 medical centers, were reviewed. The majority of patients were males (73.5%, n=97) and younger than 60 years (78%, n=103). Eleven patients had Binet stage A (8.3%), 72 (54.5%) were stage B and 49 (37.1%) had Binet stage C. Results of FISH analysis were available for 99 patients, with high risk cytogenetics of del(11q) in 21 patients (21.2%) and del(17p) in 9 cases (9.1%). The majority (56.5%, n=74) received rituximab at a dose of 500mg/m2 and the rest 375mg/m2. Almost half of the patients (49.2%, n=65) were given a reduced dose of chemotherapy (

Description: Background: Severe thrombocytopenia is an uncommon event in lower risk MDS patients, but it may significantly influence the prognosis. In fact, when it occurs, major bleeding may be a life-threatening complication. No licensed pharmacologic approach is nowadays available yet for these patients. Eltrombopag seems to be a very interesting product, but its efficacy and safeness are still to be better demonstrated. Romiplostim could be suitable too, but, at present, its safety is uncertain in MDS patients. Also danazol, an attenuated androgen, seems to have some ability to increase the platelet count in this context. Patients and methods: We retrospectively reviewed 17 thrombocytopenic patients affected by MDS, treated with danazol and observed for at least 6 months. Three patients of these had a therapy-related MDS. At the starting time of danazol therapy, the IPSS was “low” or “intermediate-1” in 16 cases; “intermediate-2” in 1 case. The IPSS-R was “very low”, “low” or “intermediate” in 16 cases; “very high” in 1 case. In 14 patients the platelet count was lower than 25x109/L, in the other 3 lower than 40x109/L, but with spontaneous bleeding. The initial dose was 600 mg/day for all the patients. The IWG criteria of response (Cheson 2006) were adopted. The outcomes were observed after 3 and 6 months from the beginning of therapy. Only descriptive statistical analysis was used. Results: At the beginning of therapy, the average platelet count of the 17 patients was 22.6 x109/L (S.D. 8.8, range 6-38). After 3 months, the therapy with danazol was ongoing in 16 patients (in 1 case the drug was discontinued due to renal failure). Platelet improvement, according to IWG criteria, was observed in 8 cases (47%). The average platelet count was 45.3x109/L (S.D. 32.9, range 4-133). The only one “high risk” patient did not show response. After 6 months danazol was still ongoing in 11 patients (in 5 cases the drug was stopped for inefficacy). The response according to IWG criteria was evident in 9 patients (52% of the initial 17 patients). The average platelet count was 66x109/L (S.D. 63.9, range 11-218). Adverse events recorded were as follows: increase in transaminases in 3 cases (in 2 of these the dose was reduced to 400 mg/day); severe but reversible renal failure in 1 case (the drug was stopped); moderate increasing of serum creatinine in 1 case (the drug was reduced to 400 mg/day); reversible cutaneous rush (the drug was reduced to 400mg/day); amenorrhea in 1 case (the only fertile woman in the series); weight loss and loss of appetite in 1 case, weight gain in 1 case. Conclusions This series confirms the efficacy of danazol to improve platelet count in approximately half of patients with severe thrombocytopenia due to “low-risk” MDS. In all patients with increased platelet count, the response was clinically significant. The response may not be immediate. Actually, there was an improvement of platelet count even after three months of therapy. The toxicity profile of this drug is low. The mechanism of action of danazol in MDS patients remains unclear. Waiting for more information on the efficacy and safety of eltrombopag from the clinical trials in progress, danazol may be a good therapeutic option for these patients. Disclosures Off Label Use: Danazol in MDS patients with severe trhombocytopenia.

Description: Abstract 4081 Introduction: Multiple myeloma (MM) accounts for 10% of hematological malignancies and 1% of cancer. It represents the second most common hematologic malignancy. The disease is characterised by plasma cell infiltration of the bone marrow, osteolytic bone lesions and the presence of a monoclonal paraprotein in the serum or urine. Interleukin-6 (IL-6) is a key molecule in the pathogenesis of MM. Its secretion occurs from the tumoral plasma cell as well as from the microenvironment. This results in myeloma cell proliferation. Tocilizumab, a humanized anti IL-6 receptor monoclonal antibody that blocks IL-6 cell-to-cell signaling, is currently being studied in MM. Most MM patients experience bone lesions. In spite of the new imaging techniques, the distinction between malignant and benign lesions remains sometimes difficult in clinical practice. The development of a more specific imaging agent may improve the accuracy of this diagnosis. Objective: Development of 99mTcHYNIC-Tocilizumab conjugate. Chemical and biological evaluation as a potential imaging agent in multiple myeloma. Methodology: 10 mg Tocilizumab (Roche) were added to 20 mg HYNIC in NaHCO3 1M, incubated for 30 min at room temperature and purified by means of PD10 column. 1 ml fractions were measured at 280nm. Conjugation of HYNIC-Tocilizumab was evaluated by mass spectrometry MALDITOF and acrylamide gel electrophoresis. 20 uL Tricine/stannous chloride in a 1:1 mass relation were added to 1 mg HYNIC-Tocilizumab in 100 uL of 0.9% NaCl. 2 mL of a solution containing 370 MBq 99mTcO4- was added. Radiochemical purity was controlled by three chromatographic systems: ITLC/NaCl 0.9%, Whatman 1MM/MEK, ITLC in BSA/EtOH-NH3-H2O (2:1:5) as stationary and mobile phase, respectively. Binding to IL-6 receptor in U266 myeloma cells was evaluated in vitro at 15, 30, 60 and 120 min. Tocilizumab was derivatized with FTIC and purified by PD10 column. Laser scanning confocal microscopy was done with an excitation/emission wavelength of 488/530 nm. Fluorescent images were obtained. Biodistribution studies were performed at 24 h in CD1 normal mice (n=3). Each mice was injected with 37 MBq of 99mTcHYNIC-Tocilizumab and sacrificed 24 hs after injection. Organs of interest were collected. Results: Mass spectroscopy MALDITOF (MH+Tocilizumab 147626 Da, M+HYNIC-Tocilizumab 148375 Da) confirmed derivatization of the antibody. This represents 5 molecules of HYNIC per molecule of the antibody. Poliacrylamide gel electrophoresis confirmed that the antibody retained its integrity after derivatization. Radiochemical purity was 88±3 %. In vitro cell binding assays confirmed the binding ability of the radiolabeled antibody to IL-6 receptor. Specificity of binding was supported by competition experiments using unlabelled antibody. Confocal microscopy proved the ability of the fluorescent antibody to recognize the IL-6 receptor in U266 myeloma cells. Biodistribution at 24 h showed blood (8.0±2.0) %act/g, liver (11±1.5) %act/g, kidney (4.0±1.0)%act/g and spleen (6±1.4) %act/g uptake with hepatic and renal elimination. Animal models of MM are being evaluated using xenografted MM cells. Conclusion: 99mTcHYNIC-Tocilizumab labeling was performed. The labeled antibody retained adequate biochemical and biological properties, which included maintenance of specific binding to IL-6 receptor. These findings indicate that this radiolabeled antibody could be used as an imaging agent in multiple myeloma. Acknowledgments: OIEA, Laboratorios Roche, Dr Gustavo Arroyo. Disclosures: No relevant conflicts of interest to declare.

Description: Background: The Israel National Cancer Registry (INCR) is a population based, national passive tumor registry established in 1960. Reporting by hospitals, laboratories, and other providers has been mandatory in Israel since 1982 and most cancer cases are registered on the basis of pathology reports and hospital records. In some hematopoietic malignancies where the diagnosis was not based on tissue pathology and patients initially received no inpatient treatment, cases may not have been reported to the registry, or reporting to the INCR may have been delayed, resulting in an underestimation of the true burden of disease. One diagnosis for which there is particular concern in this regard is CLL/SLL and here we used active surveillance to estimate the true incidence of CLL/SLL in Israel. Here we present the interim results Methods: We attempted to estimate the incidence of CLL in Israel more accurately,recognizing the fact that the exact incidence may never be known. The Israel Chronic Lymphocytic Leukemia Study Group, working with the Israel Center for Disease Control of the Ministry of Health, actively documented new cases of CLL/SLL in Israel for calendar years 2011 and 2012. All flow cytometry laboratories in Israel provided lists of patients with B cell clones. Israeli hematologists diagnosing CLL were asked to verify which of the B cell clones indicated a diagnosis of CLL, SLL, PLL or MBL and to fill out an internet-based reporting form. Diagnoses based on flow cytometry were verified by medical record review. Cases identified through active surveillance were pooled with cases known to INCR in order to estimate the true annual incidence of CLL/SLL and assess the completeness of the INCR data. Results: We identified 432 and 396 CLL/SLL cases for 2011 and 2012, respectively of whom 57.4% were males. The average age was 68.8. The corresponding age-adjusted[1]incidence rates per 100,000 (ASR) were 4.26 for 2011 and 3.79 for 2012. In comparison, the INCR registered 295 new CLL cases in 2011 (ASR=2.78) and 232 in 2012 (ASR=2.19), 54.5% of them males. The average age at diagnosis was 69.9. These data indicate a gap between true and reported incidence (1.48 and 1.60/100,000 in 2011 and 2012, respectively). However, it should be noted that the INCR will be fully updated for 2012 only by the beginning of 2015. Of active surveillance cases, 157 (2011) and 152 (2012) were registered in the INCR. Most cases missing in the INCR were diagnosed based on flow cytometry, peripheral blood samples and FISH (85.9% in 2011, 89.8% in 2012) without histo-pathological confirmation. Of the CLL/SLL cases existing in the INCR dataset for 2011-12 but not detected by active surveillance (138 in 2011; 80 in 2012), most (76.8% in 2011, 63.8% in 2012) had been diagnosed earlier and the remainder were coded as diagnoses other than CLL/SLL. Omitting these cases from the INCR dataset substantially increased the observed gaps in the true and the registered annual incidence of CLL/SLL (from 1.48 to 2.80 per 100,000 in 2011 and from 1.60 to 2.37 per 100,000 in 2012). Conclusions: The true incidence of CLL is unknown, but it is clear that there is under reporting to cancer registries. Completeness of CLL/SLL data requires accurate reporting of cases by hematologists and other care providers in the community. In Israel, this issue has been addressed by publishing updated guidelines for mandatory reporting stressing the requirement for reporting of hematologic malignancies. [1] Age-adjustment made on the basis of the world standard population Disclosures Ruchlemer: Roche: Research Funding.

Description: Abstract 4574 Leukocytosis has been documented as a risk factor for thrombotic events in various clinical conditions such as ischemic heart diseases, polycythemia vera, intensive chemotherapy and stem cell transplantation (SCT). Allogeneic (allo) SCT is characterized with a unique peri-engraftment phase simultaneously harboring T cell alloreactivity, endothelial damage, leukocyte elevation and an abundance of variable secreted cytokines. Whether leukocytes are a causative or surrogate marker for the underlying process is not concluded and whether leukocytosis is linked to the severity of acute graft-versus-host disease (aGVHD) has not been previously elucidated. The study included 59 consecutive patients undergoing matched related or unrelated allo SCT for hematological malignancies at the Rambam Medical Center, Haifa, Israel in 2010. Median age 45 years (21–66), 35 males and 24 females. Conditioning protocols were either myeloablative with busulfan/cyclophosphamide or reduced intensity (busulfan or melphalan based). Patients' clinical course and blood counts were followed for 2 months and categorized into 3 groups according to their post-engraftment leukocyte counts and leukocytosis duration. The outcome is summarized in the following table:GroupLeukocyte countNo. patientsMedian days to engraftmentMedian days to leukocyte 〉10x103/μl120-day mortalityCause of death1〈 10X103/μl16+154/162 respiratory failure,1 relapse, 1 septic shock2〉 10x103/μl (〈 7days)27+13+362/271 aGVHD (GI grade 4), 1 SOS*3〉 10x103/μl (〉 7 days)16+11+2510/164 aGVHD (GI grade 4), 4 thrombotic events**, 2 idiopathic pneumonia with end organ failure and infective complications*SOS- sinusoidal obstructive syndrome**2 SOS, 2 thrombotic thrombocytopenic purpura +120 days were chosen as the cutoff to include patients dying of the mentioned complication after day +60. The results summarized in the table suggest that patients with early and protracted leukocytosis post engraftment are at increased risk for severe and fatal complications (group 3). The 16 patients in this cohort included 9 in complete remission (CR); 7 with active disease; 5 sibling and 11 matched unrelated donor (MUD) SCTs; 6 myeloablative and 10 reduced intensity (RI) conditioning. This mix was similar to that of patients in groups 1 and 2. Leukocytosis occurring at a later phase (group 2) seems to have minimal or no impact on survival during the first 120 days post transplant. All deceased patients had documented platelet engraftment, although few did receive platelet concentrates as indicated clinically. In conclusion, protracted leukocytosis post engraftment in allo SCT patients may be an independent risk factor not only for fatal thrombotic events but also for aGVHD, mostly gastrointestinal, although larger studies are needed to confirm this. The peri-engraftment syndrome may have long-term prognostic and therapeutic implications, beyond the immediate clinical management. Given that such patients are still with endothelial dysfunction and within a rich milieu of cytokines, incorporation of anti-aggregating agents (such as anti p-selectin or GPIIb/IIIa) in the treatment protocol at this stage may have a role and should be investigated. Furthermore, mechanisms leading to such leukocytosis also need to be assessed. Disclosures: No relevant conflicts of interest to declare.

Description: Background: The ability to express the ABH antigens in oral mucosa and saliva is present in about 80% of the general population (hence called secretors) and is regulated by the Sec gene on chromosome 19q13.3, which encodes for the enzyme fut2 (α(1,2)Fucosyltransferase), resulting in the expression of blood types in body fluids, including saliva. The gene encoding for the ABH antigens that determines ABO blood type, is located on chromosome 9q34, and transcribes to the enzyme fut1. While fut1 is mainly expressed in erythroid tissue, fut2is expressed in secretory cells. The aim of the present study was to evaluate the ABO type in saliva and red blood cells of patients undergoing allogeneic SCT from ABO mismatched donors Methods: Secretion status and ABO type in saliva and blood were analyzed in patients with different hematological malignancies undergoing alloSCT from ABO incompatible donors and from healthy donors serving as controls. All study participants signed informed consent. For the determination of ABO type in saliva, following mouth rinse, 5 cc of saliva were collected from each participant into fresh tube and immediately frozen at -800C. Saliva ABH antigens were extracted and enzymes were inactivated. Secretor status and ABO type in patients' saliva were determined by inhibition test. Agglutination of diluted A, B or O typed donor red cells was tested macroscopically in the presence or absent of the extracted ABH antigens pre-incubated with anti-A, anti-B or anti-H, respectively. ABO blood type was routinely determined in patients at least every 2 weeks and time to ABO type conversion was recorded as along with all transplant-related clinical data Results: The study cohort included 30 patients (16 males and 14 females; median age 54.2, 18.8-68.5), who underwent alloSCT between Dec 2009 and Feb 2014 from an ABO incompatible donor and were available for routine follow-up. Median follow-up time from transplant to last ABO determination in saliva was 613 days (153-2789).Donors were matched related in 11, matched unrelated in 16 and mismatched unrelated in 3 cases. All grafts were from mobilized peripheral blood. Transplant from major, minor and bidirectional ABO incompatible donors was present in 9, 16 and 5 recipients, respectively. All patients engrafted. Chimerism analysis at day 30 and 100 post transplant by PCR for STR was 100% in 24/25 and 23/25 of tested patients, respectively. Median days to ABO type conversion were 64 (21-290). Of 30 patients, 26 were found to be secretors (87%).In the secretor group, 29/30(96.6%) retained original blood group in the saliva, while one patient originally typed as AB and transplanted from an A type donor, did not retain his original AB blood type in the saliva. It is not clear whether the lack of B-antigen is attributed to the acute mucosal GvHD or to a true conversion of the ABH antigen expression in the saliva Conclusion: To the best of our knowledge, this is the first report of stable chimerism of the ABO blood groups post ABO-incompatible allogeneic transplantation, such that the majority of recipients (96.6%) retained the recipient ABO group in the saliva, while expressing the donor ABO group in the blood. The significance of these findings and correlation with long-term outcome need to be further studied in larger patient cohort Disclosures No relevant conflicts of interest to declare.

Description: Background: ImMucin is a 21-mer long peptide therapeutic vaccine encoding the entire signal peptide (SP) domain of the MUC1 tumor-associated antigen, which is over expressed by most hematological tumors including multiple myeloma (MM). Results from first in man phase I/II study (VAXIL-001) demonstrated that 100 micrograms (ug) ImMucin combined with 250ug hGM-CSF is highly tolerable and can induce a robust, diversified MUC1 SP-specific T cell and B cell immunity in most patients, across major histocompatibility complex barrier. ImMucin vaccination also led to a significant decline in soluble MUC1 (sMUC1) in 9/10 patients with abnormal prevaccination levels, accompanied with disease stabilization. Methods: This current follow–up phase I/II study investigated the long term safety, quality of Life (QOL) (primary endpoint) and efficacy (both immunity and clinical response a secondary endpoint), of ImMucin, obtained in VAXIL-001 study, in participant MM subjects that didn’t required further treatment post vaccination. Patients were being evaluated once every 3 months in the first year and twice a year at the following years till progression or Q4-2015. QOL easement was assessed every visit using the SF-36 questionnaire. Immunomonitoring analysis included; CD62L+effecter memory marker, ImMucin-specific IFN-g production in CD4+ and CD8+ T-cells and anti-MUC1 SP antibody production. Clinical response was assessed according to the international myeloma working group response criteria sMUC1 levels were also evaluated every visit. Results: Long- term safety was encouraging, with no evidence for any adverse events. Additionally, the average QOL score was maintained throughout the study. Immunity, determined by INF-g production by both CD4+ and CD8+ T-cells and anti-MUC1 SP antibodies, was maintained for 6-10 and 10-12 months post vaccination respectively. The predominant T-cell phenotype during the post vaccination period was characterized with CD62L+ CD4 and CD8+ T-cells. At 13-41.3 months after the completion of the VAXIL-001 study (measured for first and last patients, respectively), 12/15 patients are alive. Median time from first vaccination was 24 months (range 2.5-41.3), at which time 10/15 patients had a PD. Disease progressed during the vaccination period (up to week 26) in 4/15 patients and during the follow up period in 6/15 patients. Notably, 5/15 patients maintained their CR (n=3) or SD (n=2). Notably, clinical response was associated with low-intermediate PDL-1 bone marrow (BM) levels prior and post vaccination, while high PDL-1 BM levels were associated with temporary response and progression. Moreover, sMUC1 levels have moderately increased during the follow up period (x〉600pg/ml), though didn’t reach initial prevaccination values. Conclusions ImMucin demonstrated an encouraging short and long-term safety profile. Vaccination induced a remarkable anti-MM immune response. However, immunity was transient suggesting a need for boosting. Interestingly, durable disease stabilization was achieved in third of the patients, continuing despite loss of immune response in peripheral blood. Moreover, the encouraging responses to subsequent therapies employed at clinical progression, suggest this novel approach to be potentially valuable in the setting of maintenance and/or early biochemical progression. Disclosures Carmon: Vaxil BioTherapeutics Ltd. : Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties. Kovjazin:Vaxil BioTherapeutics Ltd. : Employment. Shapira:Vaxil BioTherapeutics Ltd. : Consultancy.

Description: Introduction: Non-Hodgkin lymphoma (NHL) is the most common hematologic malignancy; more than 90% are B cell lymphomas and express CD-20 antigen. Rituximab® (RTX) is an IgG1κ chimeric anti-CD20 mAb that binds specifically to the CD20-antigen on B lymphocytes. Our group previously reported that 99mTc-RTX represents a promising molecular imaging agent for NHL [1]. When used for tumor imaging, intact IgG exhibits high liver uptake. Antibody fragments (Fab´s) are quickly eliminated from blood and normal tissues (except kidneys), achieving high tumor/blood and tumor/normal tissue ratios with renal clearance. The development of radiolabeled Fab´s directed against specific targets may become a new strategy for NHL staging and surveillance. Objective: To radiolabel Fab´s (RTX) with 99mTc and to perform its chemical and biological evaluation. Methodology: We performed antibody fragmentation with papain and, once purified, fragments were identified by MaldiTOF/TOF and derivatized with Suc-HYNIC as a bifunctional coupling agent. A mixture of Tricine/SnCl2.2H2O was added to Fab´s (RTX)-HYNIC and radiolabeled with 99mTcO4-. Radiochemical purity was determined by HPLC. The in-vitro radiochemical stability of the radiolabeled Fab´s were analyzed in saline and serum up to 4 h. In-vitrobinding and competition assays were performed using Ramos and Raji cell lines up to 90 min. Biodistribution studies were evaluated in normal Balb/c mice and in Raji tumor-bearing Nude mice at 0.5 and 1 h. Results: Radiochemical purity of radiolabeled Fab´s were ≥90%. The in-vitro radiochemical stability studies showed that the radioconjugate was stable and no significant transchelation was detected. In-vitro binding and competition assays confirm that after its derivatization and radiolabeling, Fab´s (RTX) retained its specificity of binding to CD-20 antigen. This results confirm that Fab´s (RTX) affinity for CD20+ NHL cells remained unaffected after its derivatization. In-vivobiodistribution studies show that radiolabeled Fab´s has renal uptake with neglectable uptake in other organs, indicating that the primary route of clearance is renal. Lymph-node/muscle ratios of 4.00 and 2.55 at 0.5 and 1 h post injection, respectively. Conclusions: Fab´s (RTX) were easily and rapidly labeled demonstrating good stability and radiochemical purity. Based on lymph-node uptake and lymph-node/muscle ratios, 99mTc-HYNIC-Fab´s (RTX) may be useful for tumor molecular imaging agent for NHL. Disclosures No relevant conflicts of interest to declare.

Description: Introduction Non-Hodgkin lymphoma (NHL) is the most common hematologic malignancy and the fifth leading cause of cancer death in the world; over 90% are B cell lymphomas and express CD-20 surface antigen [1]. CD-20 antigen is a transmembrane protein of 33-37 kDa protein located on the surface of pre-B and mature lymphocytes B [2, 3]. It is expressed in 90% of B-cell NHL [4]. Anti-CD20 antibody (Rituximab®), a specific chimeric monoclonal antibody directed against CD20 on B lymphocytes and the first monoclonal antibody approved for the treatment of CD20+ NHL. The development of new agents directed against specific targets may improve the sensitivity and specificity of imaging for its staging. Objective To radiolabel Rituximab with 99mTc and evaluate its properties as a potential imaging agent for NHL. Methodology Rituximab was derivatized with succinimidyl-hydrazinonicotinamide (Suc-HYNIC) and MALDI TOF/TOF was used to confirm the level of HYNIC conjugation to Rituximab. This antibody was radiolabeled with 99mTc using a mixture of Tricine/SnCl2.2H2O. Radiochemical purity was determined by ITLC-SG, size exclusion chromatography and HPLC. In-vitro stability was studied in solution; serum and L-Cysteine up to 24 h. In-vitro binding and competition assays were performed with Ramos and Raji NHL cell lines up to 120 min and were analyzed by laser confocal microscopy. Ramos and Raji cells were incubated with buffer to evaluate any degree of autofluorescence. Biodistribution studies were performed in normal Balb/C mice at 1, 4, 24 and 48 h (n = 5). Results HYNIC- Rituximab was efficiently labeled with 99mTc. The in-vitro radiochemical stability studies of the radiolabeled antibody showed that the complexes formed were stable and no significant transchelation was detected. In-vitro binding and displacement assays confirm that after derivatization and labeling, Rituximab retained its specificity of binding to CD-20 antigen. Immunoreactivity of HYNIC-Rituximab to Ramos and Raji cell lines was determined by direct immunofluorescence. We observed a remarkable cell membrane staining of the NHL cells. Nuclei were counterstained with 4',6-diamidino-2-phenylindole (DAPI). After its incubation with buffer, auto fluorescence was discarded. These results show that Rituximab´s affinity for NHL cells remained unaffected after its derivatization. Biodistribution studies were performed to quantify localization and clearance of the radiolabeled antibody complex in normal tissues. Significant accumulation of radioactivity was found in liver, indicating that the primary route of clearance was hepatic. Other major uptake was not found after evaluating the rest of the organs at the observed time points. Conclusions 99mTc-HYNIC-Tocilizumab was easily and rapidly labeled, with radiochemical purities greater than 90%, retaining its specificity of binding. Our results indicate that 99mTc-HYNIC-Rituximab represents a promising molecular imaging agent for NHL. Acknowledgments ANII, Roche Laboratories, Pro.In.Bio. PEDECIBA Química References [1] Swerdlow AJ. Epidemiology of Hodgkin’s disease and nonHodgkin’s lymphoma. Eur J Nucl Med Mol Imaging 2003; 30 Suppl 1:S2–12. [2] Einfield DA, Beown JP, Valentine MA, et al. Molecular cloning of the human cell CD20 receptor predicts a hydrophobic protein with multiple transmembrane domains. EMBO J 1988; 7, 711-717. [3] Valentine MA, Meier KE, Rossie S, et al. Phosphotylation of the CD20 phosphoprotein in resting B lymphocytes. Regulation by protein kinase. C J Biol Chem 1989; 264, 11282-11287. [4] Tedder TF, Boyd AW, Freedman As, et al. The B cell surface molecule B1 is functionally linked withBcell activation and differentiation. J Immunol 1985; 135, 973-979. Disclosures: No relevant conflicts of interest to declare.

Description: Mucorales-specific T cells were investigated in 28 hematologic patients during the course of their treatment. Three developed proven invasive mucormycosis (IM), 17 had infections of known origin but other than IM, and 8 never had fever during the period of observation. Mucorales-specific T cells could be detected only in patients with IM, both at diagnosis and throughout the entire course of the IM, but neither before nor for long after resolution of the infection. Such T cells predominantly produced IL-4, IFN-γ, IL-10, and to a lesser extent IL-17 and belonged to either CD4+ or CD8+ subsets. The specific T cells that produced IFN-γ were able to directly induce damage to Mucorales hyphae. None of the 25 patients without IM had Mucorales-specific T cells. Specific T cells contribute to human immune responses against fungi of the order Mucorales and could be evaluated as a surrogate diagnostic marker of IM.