Liposomes labeled with Indium-111 by a novel surface labeling method exhibits good biodistribution in vivo

Summary Aim: The purpose of this study was to assess the potential for radioimmunodetection (RAID) of murine anti-carcinoembryonic antigen (CEA) monoclonal antibody (MAb) F33-104 labeled with technetium-99m (99m-Tc) by a reduction-mediated labeling method. Methods: The binding capacity of 99m-Tc-labeled anti-CEA MAb F33-104 with CEA by means of in vitro procedures such as immunoradiometric assay and cell binding assay and the biodistribution of 99m-Tc-labeled anti-CEA MAb F33-104 in normal nude mice and nude mice bearing human colon adenocarcinoma LS180 tumor were investigated and compared with 99m-Tc-labeled anti-CEA MAb BW431/26. Results: The in vitro binding rate of 99m-Tc-labeled anti-CEA MAb F33-104 with CEA in solution and attached to the cell membrane was significantly higher than 99m-Tclabeled anti-CEA MAb BW431/261 (31.4 ± 0.95% vs. 11.9 ± 0.55% at 100 ng/mL of soluble CEA, 83.5 ± 2.84% vs. 54.0 ± 2.54% at 107 of LS 180 cells). In vivo, accumulation of 99m-Tc-labeled anti-CEA MAb F33-104 was higher at 18 h postinjection than 99m-Tc-labeled anti-CEA MAb BW431/26 (20.1 ± 3.50% ID/g vs. 14.4 ± 3.30% ID/g). 99m-Tcactivity in the kidneys of nude mice bearing tumor was higher at 18 h postinjection than at 3 h (12.8 ± 2.10% ID/g vs. 8.01 ± 2.40% ID/g of 99m-Tc-labeled anti-CEA MAb F33-104, 10.7 ± 1.70% ID/g vs. 8.10 ± 1.75% ID/g of 99m-Tc-labeled anti-CEA MAb BW431/26). Conclusion: 99m-Tc-labeled anti-CEA MAb F33-104 is a potential novel agent for RAID of recurrent colorectal cancer.

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Preparation of a Viable Population of Indium-111- Labelled Human Blood Platelets

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657048 ◽

1979 ◽

Vol 42 (05) ◽

pp. 1473-1482 ◽

Cited By ~ 17

Author(s):

A Dup Heyns ◽

P N Badenhorst ◽

H Pieters ◽

M G Lötter ◽

P C Minnaar ◽

...

Keyword(s):

Platelet Rich Plasma ◽

Blood Platelets ◽

Kinetic Studies ◽

Physiological Saline ◽

Human Platelets ◽

Autologous Plasma ◽

Platelet Suspension ◽

Viable Population ◽

Indium 111

SummaryFactors influencing labelling of human platelets with 111Indium-8-hydroxyquinoline ([111In]-oxine) in a physiological saline medium were investigated. The efficiency of labelling is influenced by time of incubation, concentration of oxine, and pH of the incubating medium. It was found that a viable platelet population could be labelled under the following conditions: (1) centrifugation of platelet rich plasma in polystyrene conical tubes at 800 g for 15 min; (2) resuspension of the platelet pellet in saline, pH 5.5; (3) incubating for 30 min at 22°C with [111In]-oxine at a concentration of 6.25 mg oxine/litre platelet suspension; (4) washing once with platelet poor autologous plasma (PPP); and (5) finally resuspending the platelets in PPP. The labelled platelets aggregated normally with collagen and ADP. Electron microscopy, done immediately after labelling, showed internal organelle reorganization characteristic of activated platelets. These ultrastructural features were reversible on incubation in PPP at 37°C for 30 min. The 111In is not released from aggregated platelets and the label does not elute from incubated platelets for at least five hr. We conclude that human platelets thus labelled are suitable for in vivo kinetic studies.

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Cell kinetics of human tumors by in vitro bromodeoxyuridine labeling.

Journal of Histochemistry & Cytochemistry ◽

10.1177/37.9.2768814 ◽

1989 ◽

Vol 37 (9) ◽

pp. 1449-1454 ◽

Cited By ~ 60

Author(s):

J S Meyer ◽

J Nauert ◽

S Koehm ◽

J Hughes

Keyword(s):

Tritiated Thymidine ◽

S Phase ◽

Dna Flow Cytometry ◽

Breast Carcinomas ◽

Brdu Labeling ◽

The Central Nervous System ◽

Labeling Method ◽

Kinetics Of

We labeled active S-phase cells in primary breast carcinomas with a modified 5-bromo-2'-deoxyuridine (BrdU) procedure using a silver-enhanced colloidal gold visualization step. Separate samples of 29 tumors were labeled with BrdU or tritiated thymidine ([3H]-dThd), and the labeling indices (LI) from the two methods were equivalent (Spearman's correlation coefficient = 0.96). Three breast carcinomas were incubated in various mixes of both BrdU and [3H]-dThd and developed sequentially for each. Paired photomicrographs showed that the same nuclei were labeled by either precursor. The in vitro method yielded LIs similar to those reported after in vivo pulse BrdU labeling for tumors of the central nervous system. The BrdU LI correlated significantly (r = 0.76, p less than 0.001) with % S-phase by DNA flow cytometry in 33 breast carcinomas. The BrdU labeling method is simpler and more rapid than the [3H]-dThd procedure (1-2 days for completion for the former, 7-10 days for the latter), and it provides an equivalent measurement of proliferative index.

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Humanization, Radiolabeling and Biodistribution Studies of an IgG1-Type Antibody Targeting Uncomplexed PSA for Theranostic Applications

Pharmaceuticals ◽

10.3390/ph14121251 ◽

2021 ◽

Vol 14 (12) ◽

pp. 1251

Author(s):

Joanna Strand ◽

Kjell Sjöström ◽

Urpo J. Lamminmaki ◽

Oskar Vilhelmsson Timmermand ◽

Sven-Erik Strand ◽

...

Keyword(s):

Prostate Cancer ◽

Specific Binding ◽

Hek293 Cells ◽

Castration Resistant Prostate Cancer ◽

Castration Resistant ◽

Biodistribution Studies ◽

Indium 111 ◽

Hormone Refractory ◽

Theranostic Applications

Metastatic castration-resistant prostate cancer is today incurable. Conventional imaging methods have limited detection, affecting their ability to give an accurate outcome prognosis, and current therapies for metastatic prostate cancer are insufficient. This inevitably leads to patients relapsing with castration-resistant prostate cancer. Targeting prostate-specific antigens whose expression is closely linked to the activity in the androgen receptor pathway, and thus the pathogenesis of prostate cancer, is a possible way to increase specificity and reduce off-target effects. We have humanized and evaluated radioimmunoconjugates of a previously murine antibody, m5A10, targeting PSA intended for theranostics of hormone-refractory prostate cancer. The humanized antibody h5A10 was expressed in mammalian HEK293 cells transfected with the nucleotide sequences for the heavy and light chains of the antibody. Cell culture medium was filtered and purified by Protein G chromatography, and the buffer was changed to PBS pH 7.4 by dialysis. Murine and humanized 5A10 were conjugated with p-SCN-Bn-CHX-A”-DTPA. Surface plasmon resonance was used to characterize the binding to PSA of the immunoconjugates. Immunoconjugates were labeled with either indium-111 or lutetium-177. Biodistribution studies of murine and humanized 5A10 were performed in mice with LNCaP xenografts. 5A10 was successfully humanized, and in vivo targeting showed specific binding in xenografts. The results thus give an excellent platform for further theranostic development of humanized 5A10 for clinical applications.

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Locating And Monitoring The Activity Of Intracardiac Thrombi With Indium-111 Platelet Scintigraphy

10.1055/s-0038-1652552 ◽

1981 ◽

Cited By ~ 1

Author(s):

M D Ezekowitz ◽

E O Smith ◽

A C Cox ◽

S W Herren ◽

F B Taylor

Keyword(s):

Artery Bypass ◽

Inhibitory Response ◽

Left Ventricular ◽

Platelet Recovery ◽

Platelet Scintigraphy ◽

Indium 111 ◽

Induced Aggregation ◽

Intracardiac Thrombi

Indium-III is 2.8 day half-life gamma emitting radionuclide which is suitable for scintigraphic study and has been used to label platelets without causing significant attenuation of function. The purpose of this study was to utilize this technique for localization of left ventricular mural thrombi in patients with regional LV dysfunction. The patient population consisted of 55 patients between the ages of 24 and 77 (53.4 ± 11.3, mean ± 1SD). Twenty-four required coronary artery bypass surgery with aneurysmectomy for intractable angina and/or heart failure. This provided an opportunity to validate the preoperative findings at surgery. Platelets were separated from 43 ml blood in ACD solution by centrifugation and were labelled in ACD:saline (1:7) solution at a pH of 6.5-7.0. A total of 3.8 ± 2.9 × 109 (mean ± 1SD) platelets labelled with 451.9 ± 111.6 μCi with a final labelling efficiency of 72.1±14.1% were injected IV. Platelet recovery at 15 minutes was 51.1 ± 17.7% (mean ± 1SD). EM studies before and after labelling showed no morphological change due to the labelling procedure. Aggregation of platelets in response to ADP and collagen was not altered significantly during the labelling process. Patients on aspirin showed the expected inhibitory effect of aspirin on collagen and ADP induced aggregation. Patients were imaged in multiple views on at least alternate days for a maximum of 8 days. Seventeen had positive studies. In those patients in which surgical confirmation of the scintigraphic studies was possible, a sensitivity of 72% and specificity of 100% was found. We conclude that: 1) Indium-111 platelet scintigraphy promises to be a reliable method of identifying intracardiac thrombi. 2) It may also be useful in monitoring thrombus activity in vivo. 3) Patients on aspirin incorporated platelets onto the thrombus surface in spite of showing the expected inhibitory response to ADP and collagen induced aggregation in vitro.

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[51] Quantification of in Vivo levels of poly(ADP-ribose): Tritium labeling method and radioimmunoassay

Methods in Enzymology - Posttranslational Modifications Part A ◽

10.1016/0076-6879(84)06053-5 ◽

1984 ◽

pp. 495-500 ◽

Cited By ~ 3

Author(s):

Masanao Miwa ◽

Takashi Sugimura

Keyword(s):

Labeling Method ◽

Tritium Labeling

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A Non-Invasive Method For Measuring Platelet Aggregation In Vivo

10.1055/s-0038-1652351 ◽

1981 ◽

Author(s):

J Morley ◽

P M Hoyle ◽

J Leyton ◽

O J Davies

Keyword(s):

Graphical Form ◽

Functional Disturbance ◽

Non Invasive ◽

Hind Limbs ◽

Minute Period ◽

Invasive Method ◽

Crystal Scintillation ◽

Indium 111 ◽

Aggregation And Disaggregation

In experimental animals, intravenous injection of ADP produces platelet accumulation in the lungs, together with thrombocytopenia. Since platelets can be isotopically labelled without gross functional disturbance, we have sought to develop a method for measurement of aggregation and disaggregation of labelled platelets in vivo.Guinea-pig platelets are labelled with Indium-111 and injected into narcotised animals (Sagital, 37 mg/kg). Two collimated crystal scintillation probes are used to monitor the thoracic region (heart and lung) (Cl) and the vascular compartment (hind limbs) (C2). An indwelling cannula (25 SWG) is inserted into a foot vein and kept patent by small volumes of heparin (100 u/ml). Intravenous ADP (10 mg/kg) causes transient accumulation of platelets within the lung, as well as thrombocytopenia, within a two minute period. During a response, counts are monitored from both probes and retained in a dedicated microcomputer, so as to permit rapid display of results in tabular and graphical form. Usually, ninety consecutive 4 sec. counts are recorded, results being expressed both as a paired difference (C1-C2) and as a ratio (C1/C2). Repeated challenge can be made with ADP and a dose-related response is obtained over the range 10-30 mg/kg. Treatment with sulphinpyrazone or prostacyclin inhibits aggregation.

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Murine eosinophils labeled with indium-111 oxine: localization to delayed hypersensitivity reactions against a schistosomal antigen and to lymphokine in vivo

Blood ◽

10.1182/blood.v61.4.732.732 ◽

1983 ◽

Vol 61 (4) ◽

pp. 732-739 ◽

Cited By ~ 3

Author(s):

TH Rand ◽

JA Clanton ◽

V Runge ◽

D English ◽

DG Colley

Keyword(s):

Lymphoid Cells ◽

Hypersensitivity Reactions ◽

Cell Type ◽

Tissue Samples ◽

Eosinophil Migration ◽

Intradermal Administration ◽

Indium 111 ◽

Eosinophil Involvement

Abstract We have evaluated a method for quantitation of eosinophil migration to stimuli in vivo. Upon transfusion into normal syngeneic mice, 111In- labeled eosinophils had an intravascular half-life of 9.5 hr and distributed predominantly into spleen, bone marrow, and liver. In either Schistosoma mansoni-infected mice or recipients of lymphoid cells from infected mice, intradermal (ear pinna) injection of the schistosomal egg antigenic preparation (SEA) elicited time-dependent accumulation of 111In-labeled eosinophils detectable by either gamma scintillation counting of tissue samples or by nuclear medicine external imaging. Intradermal administration of a lymphokine fraction (containing eosinophil stimulation promoter activity) similarly caused accumulation of 111In-labeled eosinophils. Both reactions depended on the concentration of stimulus (SEA or lymphokine). 111In-labeled neutrophils or macrophages or 125I-albumin did not preferentially accumulate at the reactions examined to the extent found with 111In- labeled eosinophils, indicating that localization of label depends on an active process and is due to eosinophils rather than a contaminating cell type. The method was used to estimate how long eosinotactic lymphokine remained at dermal sites: 60% of initial activity was present 12 hr after injection. The model is discussed with regard to the role of lymphokines in hypersensitivity reactions with eosinophil involvement, such as the granulomatous response to S. mansoni eggs.

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In Vivo Thromboscintigraphy With Indium-111-Labeled Platelets In A Dog-Catheter Model

10.1055/s-0038-1652769 ◽

1981 ◽

Author(s):

D C Price ◽

M J Lipton ◽

J A Hartmeyer ◽

R J Prager

Keyword(s):

Carotid Artery ◽

Computer Processing ◽

Catheter Insertion ◽

Scintillation Camera ◽

Data Points ◽

Indium 111 ◽

Quantitative Uptake

Autologous platelets from mongrel dogs have been labeled with 200-400 μCi Indium-111 complexed to oxine using the technique of Thakur, McAfee and others. Intraarterial thrombogenesis was studied in vivo by advancing a polyethylene angiographic catheter from a femoral into a carotid artery, then serially imaging the catheter over periods of 0.5-3 hours by scintillation camera with interfaced computer. Quantitative uptake was derived from computer processing of the studies, and compared with in vitro In-111 counts and clot weight obtained at various times by catheter excision. Labeled platelets were injected prior to or at periods of 2 or 24 hours after catheter insertion in order to evaluate both forming and preformed thrombus. Platelet In-111 radioactivity was found to peak at 30-80 minutes in newly forming thrombus and to fall thereafter. In vitro In-111 activity correlated well with wet clot weight.In-111 (% inj. dose) = 0.00209 × (mgm clot) + 0.00091 (r = 0.882) (n = 24)In vivo correlation was also linear, but with a broader scatter of data points. At the peak, In-111 uptake was 0.06044). 019% of i.d. per cm of catheter by in vitro measurement, and clot weight was 27.9±5.6 mgm per cm. Preformed thrombus picked up substantially less of the label (2 hr: 0.017±0.011% i.d./cm; 24 hr: 0.00245).001% i.d./cm) (n=6) and was not imageable in vivo. The study documents the effectiveness of this new platelet radiolabel for quantitative in vivo scintigraphy of newly forming thrombus, which can be useful for comparison of different anti-thrombogenic regimens and different biomaterials. It also indicates, however, the problems that can be anticipated in attempting to image established thrombus in vivo.

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