Antigranulocyte Monoclonal Antibody Research Articles

Leukocyte Imaging of the Diabetic Foot.

Diagnosing diabetic foot infection is often difficult, despite several available diagnostic methods. Amongst these, several imaging modalities exist to evaluate the diabetic foot in case of a suspected osteomyelitis. Nuclear Medicine, in particular, offers a variety of radiopharmaceuticals and techniques. Nowadays the gold standard radionuclide procedure, when an osteomyelitis is suspected, is represented by the use of radiolabelled leukocytes with either 99mTc-HMPAO or 111In-oxine. In this review, we describe the correct acquisition and interpretation of white blood cell scintigraphy and we provide an overview of the existing literature data of the use of this technique in the infected diabetic foot. If images are correctly acquired, displayed and interpreted, this modality reaches very high diagnostic accuracy (>95%) in detecting osteomyelitis and it allows the differential diagnosis with a soft tissue infection or inflammation. Single-photon emission computed tomography/computed tomography (SPECT/CT) in addition to planar images is mandatory to determine the extent and exact location of the infective process in both fore foot and midhint foot. With the addition of bone marrow scintigraphy using radiolabelled nanocolloids, radiolabelled white blood cell scintigraphy is also able to differentiate between Charcot neuroarthropathy and osteomyelitis, which is a challenge in the evaluation of diabetic foot. Radiolabelled anti-granulocyte monoclonal antibodies and their fragments can also be used instead of white blood cells although there is a limited experience on their usefulness in diabetic foot infection.

Clinical indications, image acquisition and data interpretation for white blood cells and anti-granulocyte monoclonal antibody scintigraphy: an EANM procedural guideline

IntroductionRadiolabelled autologous white blood cells (WBC) scintigraphy is being standardized all over the world to ensure high quality, specificity and reproducibility. Similarly, in many European countries radiolabelled anti-granulocyte antibodies (anti-G-mAb) are used instead of WBC with high diagnostic accuracy. The EANM Inflammation & Infection Committee is deeply involved in this process of standardization as a primary goal of the group.AimThe main aim of this guideline is to support and promote good clinical practice despite the complex environment of a national health care system with its ethical, economic and legal aspects that must also be taken into consideration.MethodAfter the standardization of the WBC labelling procedure (already published), a group of experts from the EANM Infection & Inflammation Committee developed and validated these guidelines based on published evidences.ResultsHere we describe image acquisition protocols, image display procedures and image analyses as well as image interpretation criteria for the use of radiolabelled WBC and monoclonal antigranulocyte antibodies. Clinical application for WBC and anti-G-mAb scintigraphy is also described.ConclusionsThese guidelines should be applied by all nuclear medicine centers in favor of a highly reproducible standardized practice.

A meta-analysis of fluorodeoxyglucose-positron emission tomography versus scintigraphy in the evaluation of suspected osteomyelitis

Functional nuclear medicine imaging techniques have become particularly important in the diagnosis of osteomyelitis. The aim of our study was to perform a meta-analysis to obtain a reliable estimate of the diagnostic performance of fluorodeoxyglucose-positron emission tomography (FDG-PET), three-phase bone scintigraphy, leukocyte scintigraphy, and monoclonal antigranulocyte antibody (MOAB) scintigraphy in the assessment of suspected osteomyelitis and to perform pairwise comparisons of the diagnostic accuracy between these different imaging modalities. A total of 23 studies representing 851 examinations that were published from January 1980 to October 2010 were reviewed. These studies evaluated the role of FDG-PET, three-phase bone scintigraphy, leukocyte scintigraphy, and MOAB scintigraphy in the assessment of suspected osteomyelitis. Systematic methods were used to identify, select, and evaluate the methodological quality of the studies and to summarize the overall findings of sensitivity and specificity. Two-sample Z-tests were conducted to evaluate for differences in sensitivity, specificity, area under the curve (AUC), and the Q* index between any two diagnostic modalities. The FDG-PET had a pooled sensitivity of 0.923, specificity of 0.920, and AUC of 0.9666, whereas for bone scintigraphy, the corresponding values were 0.827, 0.446, and 0.6514, respectively, for leukocyte scintigraphy, the corresponding values were 0.742, 0.881, and 0.9139, respectively, and for MOAB, the corresponding values were 0.883, 0.705, and 0.8897, respectively. Our meta-analysis did not find statistically significant differences in the sensitivity, specificity, AUC, and Q* index between FDG-PET and leukocyte scintigraphy. Leukocyte scintigraphy can be used with satisfactory diagnostic accuracy for detecting osteomyelitis when positron emission tomography systems are not available. The FDG-PET appears to be superior in terms of accuracy compared with other radionuclide imaging modalities.

Besilesomab for imaging inflammation and infection in peripheral bone in adults with suspected osteomyelitis

Early and accurate diagnosis of osteomyelitis, an inflammatory process of the bone caused by an infective microorganism, is essential for rapid management of the disease by antimicrobial and/or surgical intervention. Historically, diagnosis has been achieved by histological examination, but, more recently, sophisticated molecular imaging techniques (including computed tomography (CT), magnetic resonance imaging, positron emission tomography, single photon emission CT, scintigraphy) that are increasingly used to support diagnoses made from histological data have been reported. For example, scintigraphy has been used to visualize the inflammatory process in vivo using either radiolabeled leukocytes or radiolabeled antigranulocyte monoclonal antibodies (MAbs). Typically, radiolabeling is achieved using technetium-99m (radioactive half-life = 6.02 hours), and the most commonly used MAbs are the Fab fragment of the immunoglobulin (Ig)G antibody directed against the glycoprotein cross-reactive antigen-90 (sulesomab) and an IgG antibody against normal cross-reactive antigen-95 (BW 250/183, besilesomab (Scintimun ® )). The aim of the present review is to

The detection of anti-granulocyte antibodies by chemiluminescence.

Ten sera containing polyspecific anti-HLA antibodies, a rabbit antihuman leucocyte antiserum and a monoclonal anti-granulocyte antibody were used in the development of a semi-quantitative technique for the detection of anti-granulocyte antibodies. The assay measures the metabolic response of human monocytes to antibody coated (opsonized) granulocytes. Immune complexes were opsonic only in the presence of fresh human serum. Monocyte response was strongly inhibited by normal human serum and purified free immunoglobulin. The assay is simple, rapid and sensitive, and all antibodies investigated were readily detected.

Unsuspected osteomyelitis is frequent in persistent diabetic foot ulcer and better diagnosed by MRI than by 18F‐FDG PET or 99mTc‐MOAB

Prevalence, optimal diagnostic approach and consequences of clinically unsuspected osteomyelitis in diabetic foot ulcers are unclear. Early diagnosis of this infection may be crucial to ensure correct management. We conducted a prospective study in 20 diabetic patients with a chronic foot ulcer (>8 weeks) without antibiotic pretreatment and without clinical signs for osteomyelitis to assess the prevalence of clinically unsuspected osteomyelitis and to compare the value of magnetic resonance imaging (MRI), 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) and 99mTc-labelled monoclonal antigranulocyte antibody scintigraphy (99mTc-MOAB). Those with suggestive scans underwent bone biopsy for histology (n = 7). Osteomyelitis was confirmed by biopsy in seven of the 20 clinically unsuspected foot ulcers. Presence of osteomyelitis was not related to age, ulcer size, ulcer duration, duration of diabetes or HbA1c. C-reactive protein was slightly elevated in patients with osteomyelitis (35.1 +/- 16.0 mg L(-1) vs. 12.2 +/- 2.6 mg L(-1) in patients with and without osteomyelitis respectively; P = 0.07). MRI was positive in six of the seven patients with proven osteomyelitis, whereas 18F-FDG PET and 99mTc-MOAB were positive only in (the same) two patients. Of the seven patients with osteomyelitis, five had lower limb amputation and in one patient the ulcer was persisting after 24 months of follow-up. In contrast, of the 13 patients without detectable signs of osteomyelitis on imaging modalities only two had lower limb amputation and two persisting ulcers. Clinically unsuspected osteomyelitis is frequent in persisting foot ulcers and is a high risk factor for adverse outcome. MRI appears superior to 18F-FDG PET and 99mTc-MOAB in detecting foot ulcer-associated osteomyelitis and might be the preferred imaging modality in patients with nonhealing diabetic foot ulcers.

Attenuation of Folic Acid-Induced Renal Inflammatory Injury in Platelet-Activating Factor Receptor-Deficient Mice

Platelet-activating factor (PAF), a potent lipid mediator with various biological activities, plays an important role in inflammation by recruiting leukocytes. In this study we used platelet-activating factor receptor (PAFR)-deficient mice to elucidate the role of PAF in inflammatory renal injury induced by folic acid administration. PAFR-deficient mice showed significant amelioration of renal dysfunction and pathological findings such as acute tubular damage with neutrophil infiltration, lipid peroxidation observed with antibody to 4-hydroxy-2-hexenal (day 2), and interstitial fibrosis with macrophage infiltration associated with expression of monocyte chemoattractant protein-1 and tumor necrosis factor-alpha in the kidney (day 14). Acute tubular damage was attenuated by neutrophil depletion using a monoclonal antibody (RB6-8C5), demonstrating the contribution of neutrophils to acute phase injury. Macrophage infiltration was also decreased when treatment with a PAF antagonist (WEB2086) was started after acute phase. In vitro chemotaxis assay using a Boyden chamber demonstrated that PAF exhibits a strong chemotactic activity for macrophages. These results indicate that PAF is involved in pathogenesis of folic acid-induced renal injury by activating neutrophils in acute phase and macrophages in chronic interstitial fibrosis. Inhibiting the PAF pathway might be therapeutic to kidney injury from inflammatory cells.

Diagnosis of Orthopedic Infection in Clinical Practice Using Tc-99m Sulesomab (Antigranulocyte Monoclonal Antibody Fragment Fab’2)

The aim of the study was to analyze the use of Tc-99m-labeled antigranulocyte monoclonal antibody fragment Fab'2 (SMab, Leukoscan) in the diagnosis of acute osteomyelitis and articular prosthesis infection. One hundred seventeen patients (118 studies) have been included, 92 women and 25 men. Thirty-seven had a suspicion of osteomyelitis and 81 with suspicion of infection of a hip (35 patients) or a knee (45 patients) prosthesis. The mean age was 64 years. A 3-phase bone scan and a SMab scan were obtained in all patients. Antigranulocyte scans were obtained within 3 and 8 hours postinjection of 20 mCi (740 MBq) of Tc-99m-labeled antibody. Diagnosis of infection was based on bone biopsy in 8 cases and on at least 2 positive cultures in the remaining cases. Infection was ruled out with negative cultures or 1-year patient follow up with negative C-reactive protein and normal erythrocyte sedimentation rate. Sensitivity, specificity, accuracy, and negative predictive value of Tc 99m-SMab scintigraphy were: 75%, 95%, 87%, and 92% for long bone osteomyelitis and 80%, 89%, 87%, and 91% for articular prosthesis infection, respectively. Positive predictive values were 83% and 63%, respectively. Tc-99m-antigranulocyte monoclonal antibody fragment Fab'2 scintigraphy seems to be a useful method in the diagnosis of osteoarticular infection.

Infiltration of Neutrophils Is Required for Acquisition of Metastatic Phenotype of Benign Murine Fibrosarcoma Cells: Implication of Inflammation-Associated Carcinogenesis and Tumor Progression

QR-32 tumor cells, a clone derived from a murine fibrosarcoma, are poorly tumorigenic and nonmetastatic when injected into syngeneic C57BL/6 mice. However, they are converted to highly malignant ones once they have grown in vivo after being co-implanted in a subcutaneous site with a foreign body, a gelatin sponge. Early phase of inflammation induced by the gelatin sponge participates in the conversion and histological analysis shows predominant infiltration of neutrophils. The objective of this study was to determine whether the depletion of the infiltrating neutrophils has any effect on the tumor progression. Intraperitoneal administration of a monoclonal anti-granulocyte antibody, RB6-8C5 (RB6), depleted neutrophils from both the peripheral blood circulation and the local inflamed site in mice with co-implantation of QR-32 tumor cells and gelatin sponge. The RB6 administration did not inhibit either tumor development or growth of QR-32 tumor cells. In contrast, tumor cell lines established from RB6-administered mice showed a significant decrease in metastatic incidence as compared with the tumor cell lines obtained from the mice with administration of control rat IgG or saline. Metastatic ability was significantly suppressed when RB6 had been administered in the early phase (from day -2 to day 6 after implantation); however, the administration in the middle (from day 6 to day 14) or late (from day 14 to day 22) phase did not affect the metastatic ability. We confirmed the phenomena by using integrin beta(2) knockout mice that had impaired neutrophil infiltration into inflamed sites. In the knockout mice, neutrophils hardly infiltrated into the gelatin sponge and the tumors showed dramatically suppressed metastatic phenotype as compared with those in wild-type mice or nude mice. Immunohistochemical analysis demonstrated that expressions of 8-hydroxy-2'-deoxyguanosine and nitrotyrosine were parallel to those in the presence of neutrophils. These results suggested that inflammation, especially when neutrophils infiltrate into tumor tissue, is primarily important for benign tumor cells to acquire metastatic phenotype.

Rapid diagnosis of pedal osteomyelitis in diabetics with a technetium-99m-labeled monoclonal antigranulocyte antibody

An in vivo method of labeling white cells that diagnoses diabetic pedal osteomyelitis safely, rapidly, and accurately is desirable. The objectives of this investigation were to evaluate a technetium-99m-labeled monoclonal antigranulocyte antibody for diagnosing diabetic pedal osteomyelitis, compared with indium-111-labeled leukocyte and 3-phase bone imaging for this purpose. Twenty-five diabetic patients with pedal ulcers, 22 in the forefoot and 3 in the midfoot, underwent antibody, indium-111-labeled leukocyte, and technetium-99m methylene diphosphonate 3-phase bone imaging. The 1-hour antibody, 24-hour labeled leukocyte, and 3-phase bone images were interpreted separately for the presence of osteomyelitis. The antibody and labeled leukocyte images also were interpreted together with the bone images to determine if the combined study was more accurate than each individual study. There were 10 cases of osteomyelitis among the 25 patients. The sensitivity, specificity, and accuracy of the antibody were .90, .67, and .76, respectively. These results were not significantly different from those obtained with labeled leukocyte imaging: .80, .67, and .72, respectively. The antibody was significantly more specific (P = .004) than 3-phase bone imaging (.27). Interpreting the antibody together with the bone scan did not alter the results. When interpreted with the bone images, the accuracy of labeled leukocyte imaging improved from .72 to .80. This was not significantly more accurate than either the antibody or labeled leukocyte imaging alone. The data suggest that the monoclonal antigranulocyte antibody is comparable with in vitro labeled leukocyte imaging for diagnosing pedal osteomyelitis in diabetic patients, and warrants further investigation in a larger population. (The Journal of Foot & Ankle Surgery 42(1):2-8, 2003)

Antigranulocyte monoclonal antibody immunoscintigraphy in inflammatory bowel disease in children and young adolescents

Aim: Diagnostic delay for inflammatory bowel disease (IBD) is frequent, especially in paediatric patients. Scintigraphy with labelled leucocytes has been proposed as a very sensitive diagnostic tool for detecting bowel inflammation. The aim of this study was to evaluate the sensitivity and specificity of immunoscintigraphy in the diagnosis and follow‐up of children with IBD and to compare this technique with other diagnostic techniques. Methods: Sixty‐six children with histologically confirmed IBD were enrolled in the study. Twenty‐one children in whom IBD was suspected but subsequently not confirmed were used as controls. A total of 138 immunoscintigraphies were performed using 99mTechnetium‐labelled monoclonal anti‐granulocyte antibodies. Immunoscintigraphy was also compared with other diagnostic techniques. Results: Overall sensitivity of monoclonal antibody immunoscintigraphy (MoAb‐IS) in patients with clinically active disease was 94% for Crohn's disease (CD) and 85% for ulcerative colitis (UC). Ultrasonography, endoscopy and radiology were carried out at the same time in 29 patients with CD and in 6 patients with UC: sensitivity of IS was 90% compared with 76% of colonoscopy, 75% for enemas, and 55% for sonography. IS was negative (specificity) in 24% of patients with CD and in 67% of patients with UC during remission, and in 64% of controls with other causes of intestinal inflammation. Diagnostic delay was significantly shorter when compared with a historical cohort of patients. Conclusion: Immunoscintigraphy is a highly sensitive detector of intestinal inflammation in young patients with IBD and can be useful for reducing diagnostic delay. However, its specificity is low and all positive cases must be confirmed histologically.

Radionuclide imaging of the painful joint replacement: past, present and future

Differentiating aseptic loosening from infection as the cause of prosthetic joint failure is difficult because both entities are similar, clinically and histopathologically. Aseptic loosening frequently results from an immune reaction to the prosthesis. There is inflammation with an influx of histiocytes, giant cells, lymphocytes, and plasma cells. Proinflammatory cytokines and proteolytic enzymes are secreted, causing osteolysis and loosening. These same events occur in infection except that neutrophils, rarely present in aseptic loosening, are invariably present in infection. Clinical signs and symptoms, laboratory tests, x-rays and joint aspiration are insensitive, nonspecific or both. Artifacts produced by the metallic hardware hamper cross-sectional imaging modalities. Radionuclide imaging is not affected by the presence of metallic hardware and is very useful for evaluating the painful prosthesis. Bone scintigraphy, with an accuracy of 50%-70% is a useful screening test, since a normal study effectively excludes a prosthetic complication. Adding gallium-67, a nonspecific inflammation-imaging agent, improves the accuracy of bone scintigraphy to 70%-80%. The accuracy of combined leukocyte/marrow imaging, 90%, is the highest among available radionuclide studies. Its success is due to the fact that leukocyte imaging is most sensitive for detecting neutrophil mediated inflammations. Inflammatory conditions that are neutrophil-poor, even though large numbers of other leukocytes may be present, (such as the aseptically loosened joint prosthesis) go undetected. The success of leukocyte/marrow imaging is tempered by the limitations of in-vitro labeling. In-vivo labeling has been investigated and a murine monoclonal antigranulocyte antibody appears promising. Some investigations have focused on F-18 FDG imaging, although specificity is a concern with this agent.

(99m)Tc antigranulocyte monoclonal antibody imaging for the detection and assessment of inflammatory bowel disease newly diagnosed by colonoscopy in children.

This prospective study evaluated a (99m)Tc antigranulocyte monoclonal antibody Fab' imaging agent (Sulesomab) in children with inflammatory bowel disease (IBD) newly diagnosed by colonoscopy. Ten children (4 boys, 6 girls; mean age 14 years) with newly diagnosed Crohn's disease (n = 6) or ulcerative colitis (n = 4) were studied. Colonoscopy was performed in all of these patients. Within 24 h after colonoscopy, they underwent scintigraphy with (99m)Tc-Sulesomab. Abdominal/pelvic images were acquired at 30 min (planar) and 2-4 h (planar and SPECT) after injection of Sulesomab. Eighty bowel segments were evaluated semi-quantitatively by the investigators, using these three sets of images. The Pediatric Disease Activity (PDA) was correlated with the erythrocyte sedimentation rate (ESR), white blood cell (WBC) count, albumin, Kirschner's score, the Sulesomab bowel segment with maximum uptake, and the sum of Sulesomab score in each segment. The median PDA score was 26 (range 12.5-40). Three children had normal ESR and six normal WBC counts. All patients had at least one positive mucosal biopsy for IBD. While using the Kirschner's scale, the maximal severity of colonoscopy findings was graded as none (n = 2), mild (n = 4), moderate (n = 3), or severe (n = 1). Of the 59 segments evaluated with endoscopy, 35 were found to be endoscopically abnormal. The planar images identified 17 of these abnormal segments and the SPECT images 20. Nine of these ten children had abnormal bowel uptake by scintigraphy. Thus, the sensitivity of Sulesomab per patient was 90 % and per bowel segment 57 %. The correlation coefficient between the scintigraphic score for the segment with the Sulesomab maximum activity and the PDA was 0.3 (P = 0.41). In pediatric IBD assessment, planar imaging with Sulesomab did not prove very sensitive in detecting inflammation in each bowel segment. However, SPECT detected the presence of inflammation in the majority of patients. A trial comparing (99m)Tc-HmPAO-WBC with Sulesomab in a large number of patients is required.

Role of nuclear medicine in diagnosis of the infected joint replacement.

Some complications of joint replacement surgery are easily diagnosed; however, differentiating infection from aseptic loosening is difficult because these entities are remarkably similar at clinical and histopathologic examination. Clinical signs and symptoms, laboratory tests, radiography, and joint aspiration are insensitive, nonspecific, or both. Cross-sectional imaging modalities are hampered by artifacts produced by the prosthetic devices themselves. Radionuclide imaging is not affected by the presence of metallic hardware and is therefore useful for evaluating the painful prosthesis. Bone scintigraphy is useful as a screening test, despite an accuracy of only 50%-70%, because normal results essentially exclude a prosthetic complication. The addition of gallium-67, a nonspecific inflammation-imaging agent, improves the accuracy of bone scintigraphy to 70%-80%. The accuracy of combined leukocyte-marrow imaging, 90%, is the highest among available radionuclide studies. Its success is due to the fact that leukocyte imaging is most sensitive for detection of neutrophil-mediated inflammation (ie, infection). The success of leukocyte-marrow imaging is tempered by the limitations of in vitro labeling. In vivo labeling has been investigated, and a murine monoclonal antigranulocyte antibody appears promising. Some investigations have focused on fluorodeoxyglucose imaging. Although this method is sensitive, specificity is a concern.

Imaging of Infectious Arthritis

In general, infectious arthritis can be subclassified into two types 31 : pyogenic (septic) and nonpyogenic. Pyogenic arthritis is most commonly caused by Staphylococcus aureus , Neisseria gonorrhoeae , Klebsiella pneumoniae , Candida albicans , and Serratia marcescens . 33 Among the nonpyogenic arthritides are tuberculous arthritis 29,36 and infections caused by fungi, including actinomycosis, cryptococcosis, coccidioidomycosis, 2,38 histoplasmosis, and sporotrichosis. 33 Nonpyogenic arthritis can also be caused by viruses, such as smallpox, and by spirochetes, such as those responsible for syphilis and yaws. 33 In young children (less than 5 years), Haemophilus influenzae is a frequent cause of septic arthritis. 32 Infectious agents may enter the joint by directly invading the synovial membrane, either by a penetrating wound or after surgery for joint replacement. Entry to the joint can also be secondary to an infection of the adjacent soft tissues or to a blood-borne infection. 18,32 Finally, a focus of osteomyelitis in adjacent bone can also lead to infectious arthritis. A number of imaging techniques are available for diagnosis and evaluation of infectious processes that affect the joints. Although the introduction of MR imaging constituted a revolutionary change in the evaluation of musculoskeletal infections, 6 it did not diminish the role of such conventional techniques as radiography and scintigraphy. 20 Conventional radiography is still a basic diagnostic tool and should always be available when other imaging studies are analyzed. 7,14,31 The ability to diagnose infectious processes has been greatly enhanced by new approaches to radionuclide bone scanning, particularly the use of new radiopharmaceutical agents such as indium 111–labeled autologous white blood cells, 10,21 technetium 99m hexamethylpropylene-amino-oxime, 13 radiolabeled human polyclonal IgG 9 indium 111– or technetium 99m–labeled chemotactic peptide analogues, 12 or immunoscintigraphy with technetium 99m–labeled antigranulocyte monoclonal antibodies. 16 Also of value are other more effective modalities, which are discussed later. It must be stressed, however, that when there is a clinical suspicion of infectious arthritis, particularly septic arthritis, the most rapid approach to final diagnosis, and to avoid irreversible osseous and articular sequelae, is to perform a joint aspiration. 26,37

Ultrasound in Crohn’s disease of the small bowel

Objective: The purpose of this work is to prospectively evaluate high resolution ultrasonography with graded compression in the ability to detect Crohn's disease of the small bowel (CDSB) together with its complications and activity signs, compared with enteroclysis, CT and immunoscintigraphy in the mirror of the final diagnosis. Methods and material: In a series of 73 consecutive patients, who were referred for enteroclysis with suspected Crohn's disease of the small bowel computed tomography (CT), ultrasound (US), immunoscintigraphy with 99mTc labeled monoclonal antigranulocyte antibody (AGAb) examinations were performed within 10 days from each other. For the final evaluation the diagnosis of CDSB was based on combination of clinical and enteroclysis findings (73 cases) and in 17 cases additional surgical and pathological data were available. The results of other modalities were blinded to the radiologists performing and reading out the exams. The diagnostic values of each modality was assessed also in those 18 patients, who had early Crohn’s disease. In the group of 43 patients with proven CDSB who had all the four imaging modalities, the modalities were compared in their ability to demonstrate various pathological conditions related to CD. Increased (>500 ml/min) flow measured by Doppler US in the superior mesenteric artery and increased color signs in the gut wall seen by power Doppler sonography were compared to CDAI. Results: Of the 73 patients the combination of enteroclysis and clinical tests demonstrated CDSB in 47. The sensitivity, specificity and accuracy of ultrasound were 88.4, 93.3 and 90.4%, respectively. Enteroclysis was the most accurate method. CT was more sensitive than US, but less specific. The accuracy of US, CT and scintigraphy were similar. In the group of 18 patients, who had early CDSB, the sensitivity of US decreased to only 67%, CT and scintigraphy had higher values. Intra- and perimural abscesses, and sinus tracts were also more frequently visualized by US, especially if they were small. US was superior than CT in detecting stenoses and skip lesions, but inferior to enteroclysis. US and CT detected more fistulas, than enteroclysis. Compared to CT, US detected more cases with mesenteric lymphadenopathy, equal cases with abscesses and free peritoneal fluids. In detecting mesenteric inflammatory proliferation CT, and in detecting colonic involvement CT and immunoscintigraphy were slightly superior than graded compression US. Patterns of mural stratification detected by ultrasound correlated well with the enteroclysis severity stages. There was only 59% agreement between increased superior mesenteric artery flow detected by Doppler sonography and CDAI, and 60.5% agreement between increased number of Color pixels in the gut wall measured by power Doppler and increased CDAI. Conclusion: High resolution graded compression sonography is a valuable tool for detecting small intestinal Crohn's disease. It has similar diagnostic values as CT. However in early disease the sensitivity substantially decreases. In known Crohn's disease for following disease course, evaluating relapses and extramural manifestations US is an excellent tool. Doppler and Power Doppler activity measurements do not correlate well with the more widespread clinical activity index.

The crucial role of granulocytes in the early host defense against Strongyloides ratti infection in mice.

The involvement of granulocytes in the host early defense against the nematode, Strongyloides ratti, was studied. It was confirmed that granulocytes were effectively depleted for 4 days by anti-granulocyte monoclonal antibody (anti-Gr-1). To examine the involvement of granulocytes in the host defense against migrating larvae, 2,000 S. ratti infective larvae (L3) were inoculated subcutaneously 1 day after antibody treatment. The number of S. ratti eggs secreted in feces (EPG) was higher in the granulocyte-depleted group than in the control group. The number of migrating larvae also increased in the granulocyte-depleted group in accordance with the increase in EPG. Therefore granulocytes are crucial for the host early defense against migrating larvae of S. ratti. Next, the involvement of granulocytes in the intestinal early defense was examined. Mice were treated with the antibody on day 3 post-infection. On that day, almost all inoculated larvae reached the intestine and molted to become adults. EPG on day 5 post-infection was increased by the antibody treatment, but no effect was observed on intestinal worm numbers. The fecundity (EPG/worm number) of S. ratti adult worms in the granulocyte-depleted group was higher than that in the control group. Thus granulocytes are also involved in the intestinal early defense through suppressing fecundity of the adult worms. On the other hand, the depletion of granulocytes had no effect on the late adaptive response against S. ratti adult worms (e.g. number of intestinal mucosal mast cells, time of worm expulsion). These results suggest that granulocytes are mainly involved in the host early defense against parasites.

Granulocyte accumulation in ischemic/reperfused myocardium: Assessment with a technetium-99m—labeled antigranulocyte monoclonal antibody in the dog

This study tested the usefulness of technetium-99m—labeled antigranulocyte monoclonal antibody BW250/183 (AGMAb) for identifying granulocyte accumulation in ischemic/reperfused canine myocardium. In dogs with 90 minutes coronary artery occlusion and 180 minutes reperfusion (n = 8), ischemic/reperfused myocardial samples demonstrated 8.5 ± 2.4 times more Tc-99m—AGMAb accumulation than nonischemic samples. Dogs given Tc-99m—labeled nonspecific human immunoglobulin instead of Tc-99m—AGMAb (n = 3) had about half as much accumulation (4.5 ± 1.6, P < .05). Ex vivo myocardial imaging of Tc-99m—AGMAb demonstrated marked uptake in infarcted regions identified by absent triphenyl tetrazolium chloride staining. The amount of uptake was inversely related to the severity of ischemia (determined by radioactive microspheres) and directly correlated with tissue myeloperoxidase activity, a specific marker of granulocyte accumulation. No increase in Tc-99m—AGMAb uptake occurred in dogs with 90 minutes ischemia and no reperfusion (n = 3) or 15 minutes ischemia and 180 minutes reperfusion (n = 2). In conclusion, Tc-99m—AGMAb is taken up in reperfused infarcted myocardium by both nonspecific and specific mechanisms. Because the amount of uptake reflects myocardial granulocyte accumulation, Tc-99m—AGMAb combined with nuclear imaging techniques may be useful for studying inflammatory processes in the heart in experimental animal models and human beings.

Isolation of rainbow trout neutrophils with an anti-granulocyte monoclonal antibody

A magnetic cell sorting system has been optimised for the purification of rainbow trout neutrophils using a monoclonal antibody (E3D9) raised against Atlantic salmon neutrophils. The purified neutrophils have good viability (85%) and purity (~92%), and were functional in respiratory burst and migration assays. The isolated neutrophils responded rapidly to PMA stimulation, producing levels of superoxide anion (4.85 nmols superoxide min −1/10 6 cells) approximately twice as high as macrophages from the same species. In the migration assay, there was a four-fold increase in migrating cells using the purified neutrophils compared with unfractionated blood leucocytes, and a relatively high neutrophil migratory activity was seen in the absence of serum.

Detection of metastatic bone lesions in patients with prostate carcinoma

Bone scintigraphy has been shown to be sensitive in determining bone involvement in patients with malignancy, but it does not allow the assessment of bone marrow lesions in early disease. The aim of this study was to detect bone marrow invasion using 99Tcm-labelled monoclonal antigranulocyte antibody (AgMoAb) in patients with prostate carcinoma. We studied 56 patients whose mean (+/- S.D.) age was 67 +/- 7 years. The mean prostate-specific antigen level was 6.1 ng ml-1 (normal range 0-5 ng ml-1). Twelve patients were in stage A, 16 in stage B, 17 in stage C and 11 in stage D. Six patients had been receiving chemotherapy and four patients radiotherapy before scanning. Bone scans were obtained 2 h after the intravenous injection of 555 MBq 99Tcm-methylene diphosphonate (99Tcm-MDP). Within a week, bone marrow imaging was performed 4 and 24 h after the injection of 555 MBq 99Tcm-AgMoAb. Metastatic bone lesions were detected on the 99Tcm-MDP scans of 14/56 (25%) patients, of whom one was in stage A, two in stage B, four in stage C and seven in stage D. Hypoactive lesions in bone marrow were detected in 25/56 (45%) patients, of whom two were in stage A, five in stage B, seven in stage C and 11 in stage D. Bone marrow metastases were confirmed in six patients by computed tomography (CT) and magnetic resonance imaging (MRI) and in two patients by marrow aspiration biopsy. A false-positive immune scintigram was found in three patients previously receiving radiotherapy or chemotherapy. We suggest that 99Tcm-AgMoAb scintigraphy is a sensitive procedure for the detection of bone marrow lesions. However, the reason for false-positive and false-negative results should be considered and CT, MRI and marrow biopsy should be performed when clinically necessary.