Nuclear medicine offers several techniques and procedures to image infection, but radiolabelled a... more Nuclear medicine offers several techniques and procedures to image infection, but radiolabelled autologous white blood cells (WBCs) are still the gold standard. These cells are usually labelled with 111In or 99mTc bound to a hydrophobic chelating agent that allows these isotopes to pass through the plasma membrane and enter in the cytoplasm. The most common compound in Europe is HMPAO that efficiently chelates 99mTc. However, up to 20–40% of the complex is released from the cells in the first few hours. The aim of this study was to radiolabel a new compound, (S3CPh)2 (S2CPh)-complex (SSS-complex) with 99mTc and compare its binding kinetics and specificity for WBC with HMPAO. The SSS-complex was labelled with 99mTc and analysed by iTLC and RP-HPLC. In vitro quality controls included a stability assay in serum and saline. Results showed a labelling efficiency of 95 ± 1.2% and 98 ± 1.4% for 99mTc-SSS-complex and 99mTc-HMPAO, respectively (p=ns). 99mTc-SSS-complex was stable in serum an...
Aim. Aim of the present study was to compare in vitro the labelling efficiency (LE) and cell viab... more Aim. Aim of the present study was to compare in vitro the labelling efficiency (LE) and cell viability (TBE) of autologous leukocytes labelled with 99mTc-SnF2 and 99mTc-HMPAO, and to evaluate the quantity and quality of spontaneously released 99mTc (SR) from labelled cells at several time points after labelling. Methods. A total of 14 patients with different diseases and 18 normal subjects were included in this study. A blood sample was collected from each patient; purified autologous leukocytes were divided into 2 samples and labelled with 99mTC-SnF2 and 99mTC-HMPAO. LE was evaluated at the end of labelling and TBE and SR were evaluated at 10 min and 1 h, 2 h and 4 h after labelling. Results. LE of 99mTc-SnF2-WBC was higher than 99mTc-HMPAO-WBC (61.2±18.7% and 43.3±11.3; p< 0.0001) and we found an inverse correlation between blood glucose and labelling efficiency for both methods (p=0.02). Minimal differences were also observed between 2 methods after 10 min and 1 h, as far as the cell viability is concerned. The percentage of radioactivity spontaneously released from 99mTc-SnF2-WBC was significantly higher compared to 99mTc-HMPAO-WBC at each time point. Radioactivity released from labelled cells was predominantly 99mTC-SnF2 and 99mTC-HMPAO With few free 99mTc (<20%). Conclusion. Both radiopharmaceuticals are not toxic for WBC. Labelling with 99mTc-SnF2 give a higher LE than with 99mTc-HMPAO; however, radiolabelled colloids are more released from labelled cells over a period of 4 h. While 99mTc-HMPAO is physiological excreted into gastrointestinal tract, 99mTC-SnF2 can be re-uptaken in vivo by reticulo-endothelial cells of liver and spleen. These findings suggest that 99mTc-SnF2-WBC might be better than 99mTc-HMPAO-WBC for studying inflammatory bowel diseases
The quarterly journal of nuclear medicine and molecular imaging : official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR), [and] Section of the Society of Radiopharmaceutical Chemistry and Biology, 2014
The quarterly journal of nuclear medicine and molecular imaging : official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR), [and] Section of the Society of Radiopharmaceutical Chemistry and Biology, 2010
Monoclonal antibodies, which include murine, chimeric, humanized and fully human antibodies, bind... more Monoclonal antibodies, which include murine, chimeric, humanized and fully human antibodies, bind to their target receptors with high affinity and specificity. In the last two decades several different monoclonal antibodies have been approved by the Food and Drug Administration for therapeutic purposes, and some of these and others have also been radiolabelled for diagnostic and therapeutic purposes. This field is in continuous evolution and this overview highlights the role of radiolabelled antibodies in research and clinical setting.
The quarterly journal of nuclear medicine and molecular imaging : official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR), [and] Section of the Society of Radiopharmaceutical Chemistry and Biology, 2007
This pilot study reports on the uptake of (123)I-interleukin 2 (IL-2) in metastatic renal cell ca... more This pilot study reports on the uptake of (123)I-interleukin 2 (IL-2) in metastatic renal cell carcinoma (MRCC) patients and its relationship to prognostic factors of response or failure of MRCC to cytokines treatment. Nine consecutive patients with MRCC underwent an (123)I-IL-2 scan (6 male and 3 female; mean age 64 years; range 51-78). Uptake in metastases was related to a summed score of 4 independent factors, predictive of rapid progression under cytokine treatment as defined by Negrier et al. Four patients presented with metastases at one site, 4 at 2 sites and one patient at 3 different sites. Summed scores were: 5 patients had a summed score of 1; 3 a summed score of 2 and 1 patient a summed score of 3. Uptake of (123)I-IL-2 by tumor tissue was found in only 2 patients. Uptake occurred in 1 patient with a summed score of 3 and in 1 with a summed score of 2. In this small series of patients with MRCC, (123)I-IL-2 uptake was found in tumors of 2 patients who less likely will be...
The diurnal variation of peripheral white cells and in particular of different lymphocyte subsets... more The diurnal variation of peripheral white cells and in particular of different lymphocyte subsets has been investigated in 11 normal subjects. Monoclonal antibodies (Mab) phenotyping total T lymphocytes (UCHT1), cytotoxic/suppressor (UCHT4), helper T cells (Leu 3a), B lymphocytes (231) and K/NK cells (H25) have been used. In addition to the traditional parametric statistics, the chronobiological approach of cosinor was adopted in order to inferentially obtain the waveform covering the 24-hr period. Cosinor analysis validated the existence of a significant rhythm for leucocytes (p = 0.04, lymphocytes (p = 0.03), and Leu 3a positive cells (p = 0.04). The best fitting period was equal to 28 hr. No circadian rhythm was documented for lymphocyte subsets positive for Mab UCHT4, 231, H25, by testing the variability with a frequency ranging from 1 cycle every 12hr to 1 cycle every 28 hr. By the non-inferential analysis of temporal curves, a significant peak of Leu 3a positive cells at 20.00...
Acute inflammatory response to lipopolysaccharide (LPS) exposure is typically associated with car... more Acute inflammatory response to lipopolysaccharide (LPS) exposure is typically associated with cardiac myocyte apoptosis, which is difficult to quantify because of heart tissue specificity. We report here that radioiodinated Annexin V (I-AnxV), a specific ligand of phosphatidylserine exposed by apoptotic cells, allows tissue detection of apoptosis in LPS-treated rat hearts. Heart I-AnxV uptake was significantly increased in all cardiac territories of LPS-treated rats. In contrast, I-human serum albumin myocardial uptake was only slightly increased in LPS-treated rat hearts, suggesting limited changes in vascular protein permeability. Autoradiography of endotoxin-treated rat heart sections with I-AnxV in association with deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling and caspase 3 staining allows identification of double positive cardiac myocytes. Inhibition of apoptosis by caspase inhibitors (i.e., ZVAD.fmk and DEVD.cmk) reduced I-AnxV myocardial uptake in LPS-treated rats. Eventually, endotoxin-treated rats displayed pathological uptake of Tc-annexin in the cardiac mediastinal region whereas zVAD.fmk reduced Tc-annexin mediastinal uptake. Our results show that radioactive I-AnxV signal emerging from LPS-treated rat hearts could be related to the activation of caspase-dependent apoptotic pathway in cardiac myocytes.
Nuclear medicine offers several techniques and procedures to image infection, but radiolabelled a... more Nuclear medicine offers several techniques and procedures to image infection, but radiolabelled autologous white blood cells (WBCs) are still the gold standard. These cells are usually labelled with 111In or 99mTc bound to a hydrophobic chelating agent that allows these isotopes to pass through the plasma membrane and enter in the cytoplasm. The most common compound in Europe is HMPAO that efficiently chelates 99mTc. However, up to 20–40% of the complex is released from the cells in the first few hours. The aim of this study was to radiolabel a new compound, (S3CPh)2 (S2CPh)-complex (SSS-complex) with 99mTc and compare its binding kinetics and specificity for WBC with HMPAO. The SSS-complex was labelled with 99mTc and analysed by iTLC and RP-HPLC. In vitro quality controls included a stability assay in serum and saline. Results showed a labelling efficiency of 95 ± 1.2% and 98 ± 1.4% for 99mTc-SSS-complex and 99mTc-HMPAO, respectively (p=ns). 99mTc-SSS-complex was stable in serum an...
Aim. Aim of the present study was to compare in vitro the labelling efficiency (LE) and cell viab... more Aim. Aim of the present study was to compare in vitro the labelling efficiency (LE) and cell viability (TBE) of autologous leukocytes labelled with 99mTc-SnF2 and 99mTc-HMPAO, and to evaluate the quantity and quality of spontaneously released 99mTc (SR) from labelled cells at several time points after labelling. Methods. A total of 14 patients with different diseases and 18 normal subjects were included in this study. A blood sample was collected from each patient; purified autologous leukocytes were divided into 2 samples and labelled with 99mTC-SnF2 and 99mTC-HMPAO. LE was evaluated at the end of labelling and TBE and SR were evaluated at 10 min and 1 h, 2 h and 4 h after labelling. Results. LE of 99mTc-SnF2-WBC was higher than 99mTc-HMPAO-WBC (61.2±18.7% and 43.3±11.3; p< 0.0001) and we found an inverse correlation between blood glucose and labelling efficiency for both methods (p=0.02). Minimal differences were also observed between 2 methods after 10 min and 1 h, as far as the cell viability is concerned. The percentage of radioactivity spontaneously released from 99mTc-SnF2-WBC was significantly higher compared to 99mTc-HMPAO-WBC at each time point. Radioactivity released from labelled cells was predominantly 99mTC-SnF2 and 99mTC-HMPAO With few free 99mTc (<20%). Conclusion. Both radiopharmaceuticals are not toxic for WBC. Labelling with 99mTc-SnF2 give a higher LE than with 99mTc-HMPAO; however, radiolabelled colloids are more released from labelled cells over a period of 4 h. While 99mTc-HMPAO is physiological excreted into gastrointestinal tract, 99mTC-SnF2 can be re-uptaken in vivo by reticulo-endothelial cells of liver and spleen. These findings suggest that 99mTc-SnF2-WBC might be better than 99mTc-HMPAO-WBC for studying inflammatory bowel diseases
The quarterly journal of nuclear medicine and molecular imaging : official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR), [and] Section of the Society of Radiopharmaceutical Chemistry and Biology, 2014
The quarterly journal of nuclear medicine and molecular imaging : official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR), [and] Section of the Society of Radiopharmaceutical Chemistry and Biology, 2010
Monoclonal antibodies, which include murine, chimeric, humanized and fully human antibodies, bind... more Monoclonal antibodies, which include murine, chimeric, humanized and fully human antibodies, bind to their target receptors with high affinity and specificity. In the last two decades several different monoclonal antibodies have been approved by the Food and Drug Administration for therapeutic purposes, and some of these and others have also been radiolabelled for diagnostic and therapeutic purposes. This field is in continuous evolution and this overview highlights the role of radiolabelled antibodies in research and clinical setting.
The quarterly journal of nuclear medicine and molecular imaging : official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR), [and] Section of the Society of Radiopharmaceutical Chemistry and Biology, 2007
This pilot study reports on the uptake of (123)I-interleukin 2 (IL-2) in metastatic renal cell ca... more This pilot study reports on the uptake of (123)I-interleukin 2 (IL-2) in metastatic renal cell carcinoma (MRCC) patients and its relationship to prognostic factors of response or failure of MRCC to cytokines treatment. Nine consecutive patients with MRCC underwent an (123)I-IL-2 scan (6 male and 3 female; mean age 64 years; range 51-78). Uptake in metastases was related to a summed score of 4 independent factors, predictive of rapid progression under cytokine treatment as defined by Negrier et al. Four patients presented with metastases at one site, 4 at 2 sites and one patient at 3 different sites. Summed scores were: 5 patients had a summed score of 1; 3 a summed score of 2 and 1 patient a summed score of 3. Uptake of (123)I-IL-2 by tumor tissue was found in only 2 patients. Uptake occurred in 1 patient with a summed score of 3 and in 1 with a summed score of 2. In this small series of patients with MRCC, (123)I-IL-2 uptake was found in tumors of 2 patients who less likely will be...
The diurnal variation of peripheral white cells and in particular of different lymphocyte subsets... more The diurnal variation of peripheral white cells and in particular of different lymphocyte subsets has been investigated in 11 normal subjects. Monoclonal antibodies (Mab) phenotyping total T lymphocytes (UCHT1), cytotoxic/suppressor (UCHT4), helper T cells (Leu 3a), B lymphocytes (231) and K/NK cells (H25) have been used. In addition to the traditional parametric statistics, the chronobiological approach of cosinor was adopted in order to inferentially obtain the waveform covering the 24-hr period. Cosinor analysis validated the existence of a significant rhythm for leucocytes (p = 0.04, lymphocytes (p = 0.03), and Leu 3a positive cells (p = 0.04). The best fitting period was equal to 28 hr. No circadian rhythm was documented for lymphocyte subsets positive for Mab UCHT4, 231, H25, by testing the variability with a frequency ranging from 1 cycle every 12hr to 1 cycle every 28 hr. By the non-inferential analysis of temporal curves, a significant peak of Leu 3a positive cells at 20.00...
Acute inflammatory response to lipopolysaccharide (LPS) exposure is typically associated with car... more Acute inflammatory response to lipopolysaccharide (LPS) exposure is typically associated with cardiac myocyte apoptosis, which is difficult to quantify because of heart tissue specificity. We report here that radioiodinated Annexin V (I-AnxV), a specific ligand of phosphatidylserine exposed by apoptotic cells, allows tissue detection of apoptosis in LPS-treated rat hearts. Heart I-AnxV uptake was significantly increased in all cardiac territories of LPS-treated rats. In contrast, I-human serum albumin myocardial uptake was only slightly increased in LPS-treated rat hearts, suggesting limited changes in vascular protein permeability. Autoradiography of endotoxin-treated rat heart sections with I-AnxV in association with deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling and caspase 3 staining allows identification of double positive cardiac myocytes. Inhibition of apoptosis by caspase inhibitors (i.e., ZVAD.fmk and DEVD.cmk) reduced I-AnxV myocardial uptake in LPS-treated rats. Eventually, endotoxin-treated rats displayed pathological uptake of Tc-annexin in the cardiac mediastinal region whereas zVAD.fmk reduced Tc-annexin mediastinal uptake. Our results show that radioactive I-AnxV signal emerging from LPS-treated rat hearts could be related to the activation of caspase-dependent apoptotic pathway in cardiac myocytes.
Uploads