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Biomedical subjects

J O Olsen

Publications and source records attributed to J O Olsen.

At least 19 recordsLinked to original sources
PubMed2002

Cellular activation responses in blood in relation to lipid pattern: healthy men and women in families with myocardial infarction or cancer.

High cholesterol is a well-established risk factor of myocardial infarction (MI). Since monocytes play a pivotal role in the development of atherosclerosis, one might anticipate that their functional properties are very important in relation to MI. In the present study, we have explored how the lipopolysaccharide (LPS)-induced reactivity of monocytes in whole blood in vitro relates to the serum lipid profile of healthy subjects with a history of MI or cancer in their close family. Twenty of the 54 subjects (of the total 266 test subjects) in the MI families had moderately high cholesterol (7.1-10.2 mmol/l), whereas 34 had normal cholesterol. Nineteen of the normocholesterol individuals had hyperactive monocytes (high responders), whereas 15 had monocytes responding normally. Two of the 20 subjects in the high cholesterol group had hyperactive monocytes. LPS-induced tissue factor, tumour necrosis factor-alpha and interleukin-6 were on the average three to four times higher in the normocholesterol group compared with the moderately hypercholesterol group, and hence no positive correlation was found between hyperactive monocytes and cholesterol. The 42 subjects in the families with cancer had normal cholesterol, and two of these subjects had very high LPS-induced tissue factor, tumour necrosis factor-alpha and interleukin-6, whereas eight of the 170 subjects without MI or cancer in their family were high responders. This further substantiates the notion that moderately high cholesterol is not associated with enhanced monocyte activation in whole blood. Hyperactive peripheral blood monocytes are suggested to be associated with a significant risk factor in developing coronary heart disease.

Adolescent↗
PubMed2000

Induction of tissue factor expression in whole blood: lack of evidence for the presence of tissue factor expression in granulocytes.

The present investigation was undertaken to explore the effect of platelets, tumor necrosis factor (TNF) and phorbel ester [phorbol 12-myristate 13-acetate (PMA)] on lipopolysaccharide (LPS)-induced tissue factor (TF) activity and TF antigen by using Western blot and ELISA-techniques. LPS was found to induce correlating levels of TF antigen and the activity in monocytes. TNF and PMA, when used alone, failed to induce TF activity and the antigen in monocytes, but enhanced the LPS-induced TF activity and the antigen by 2 to 3-fold. Addition of platelet rich plasma to isolated blood cells enhanced the LPS-induced TF activity but not the antigen levels in monocytes. In contrast to whole platelets, platelet lysates enhanced both LPS-induced TF activity and the antigen. Granulocytes isolated from heparinized plasma incubated for 2 or 24 h with LPS alone or together with PMA, failed to generate TF antigen or the activity. Although granulocyte preparations isolated from whole blood that was incubated for 24 h with LPS and PMA apparently possessed a significant amount of TF activity and the antigen, this could be accounted for by trace levels of contaminating monocytes. Upregulation of LPS-induced TF activity but not the antigen by platelets in the presence of granulocytes suggests that the increased TF activity could be the result of PS enrichment of monocytes by fusion or platelets with activated monocytes.

Antigens↗
PubMed1999

The effect of red wine on the fibrinolytic system and the cellular activation reactions before and after exercise.

The effect of red wine drinking was tested on fibrinolytic parameters and blood cells in nine healthy students at rest and after acute exercise. The subjects were randomly assigned in a crossover design to one of three treatment regimes: control situation, low-dose wine group, and high-dose wine group. Blood samples were drawn just prior to experimental start, at 2 and 4 hours, and the next morning at 8:00 a.m., at 8:30 a.m. just after exercise, and 2 hours after exercise. The fibrinolytic potential was measured by whole blood clot lysis time (WBCLT), tissue plasminogen activator, and plasminogen activator inhibitor-1 (PAI-1) antigens in plasma. A whole blood system was used to test the reactivity of blood cells by stimulating hirudinized blood with 5 ng/mL lipopolyusaccharide (LPS) for 2 hours at 37 degrees C and measurements of tissue necrosis factor alpha and interleukin-8 (IL-8) in the plasma. Intake of red wine caused impaired fibrinolysis shown by prolonged WBCLT (3.6, 20.7, and 55.7%, respectively, for control, low- and high-dose wine groups) due to increase in PAI-1 antigen (-0.8, 4.8, and 11.0 ng/mL, respectively, in the three groups). There was no effect of the red wine the next morning on the fibrinolytic system. A strong correlation was observed between WBCLT and PAI-1 antigen (p<0.0001). Acute exercise caused an immediate rise in both tissue plasminogen activator antigen and PAI-1 antigen levels and WBCLT was significantly shortened. In contrast to that of the wine groups, 2 hours after exercise WBCLT was prolonged in the control group, but not significantly so. Thus the red wine has a negative effect on the fibrinolytic system during rest, but may have a positive effect after strenuous exercise. The red wine had no immediate effect on LPS-induced tissue necrosis factor alpha or IL-8 production, although there was a tendency for higher cytokine production in the control group compared to the wine groups during and just after intake of wine. The next morning after exercise, the LPS-induced IL-8 production increased 137, 89, and 96%, respectively, in control, low-, and high-dose wine groups, probably due to a rise in epinephrine and activation of platelets. Although not significantly so, there was a tendency for red wine intake in the evening to suppress the reactivity of the cells after physical exercise the subsequent morning. It is suggested that the negative effect of red wine ingestion may be due to the toxic effect of ethanol on hepatocytes or adipose tissue and subsequent release of PAI-1, whereas the positive effect may be due to the red wine suppression of platelet activation and release of PAI-1 from activated platelets. It is proposed that at least part of the beneficial effect of red wine ingestion may be associated with the downregulation of cytokine production.

Adult↗
PubMed1999

Routine preoperative lymphoscintigraphy is not necessary prior to sentinel node biopsy for breast cancer.

BACKGROUND: This prospective study was performed to ascertain the added benefit of lymphoscintigraphy to a standard method of intraoperative lymphatic mapping and sentinel node biopsy for breast cancer. METHODS: Patients with invasive breast cancer were injected with 99mTc sulfur colloid prior to sentinel node biopsy; preoperative lymphoscintigraphy was then performed in half of the patient population. RESULTS: Sentinel node identification was possible in 45 of 50 patients (90%). All 14 patients (31%) with axillary nodal metastases had at least one histologically positive sentinel node (0% false negative rate). Lymphoscintigraphy revealed sentinel nodes in 17 of the 24 patients (70.8%) imaged. All 17 of these patients had one or more axillary sentinel nodes identified using intraoperative lymphatic mapping. In addition, 5 of 7 patients with a negative preoperative lymphoscintogram had an axillary sentinel lymph node(s) identified intraoperatively. None of the tumors showed drainage to the internal mammary lymph node chain by lymphoscintigraphy despite the fact that there were 5 patients with inner quadrant tumors. There was no significant advantage with respect to sentinel lymph node localization (91.7% versus 88.5%, P = not significant) or false negative rate (0%, both groups, P = not significant) in the group undergoing preoperative lymphoscintigraphy when compared with the patients in whom lymphoscintigraphy was not performed. CONCLUSIONS: Preoperative lymphoscintigraphy adds little additional information to intraoperative lymphatic mapping, and its routine use is not justified.

Axilla↗
PubMed1999

Immunoscintigraphy with indium-111-capromab pendetide: evaluation before definitive therapy in patients with prostate cancer.

OBJECTIVES: No standard noninvasive diagnostic test reliably differentiates patients with organ-confined prostate cancer from those with lymph node metastases. The ability of a radiolabeled monoclonal antibody, indium-111 (111ln)-capromab pendetide, to identify sites of metastatic disease in patients at moderate to high risk of nodal involvement was investigated. METHODS: The study prospectively evaluated 160 patients with prostate cancer scheduled to undergo pelvic lymph node dissection (PLND) before or during definitive treatment. All were at relatively high risk of nodal involvement by virtue of significantly elevated baseline prostate-specific antigen (PSA) values, Gleason scores, and/or locally advanced clinical stages of disease. The histologic findings of the PLNDs were compared with the results of immunoscintigraphy, computed tomography, and magnetic resonance imaging. RESULTS: Among the 152 evaluable patientS studied with 111In-capromab pendetide before PLND, the sensitivity of immunoscintigraphy for lymph node detection was 62% and the specificity was 72%; the positive predictive value was 62% and the negative predictive value was 72%. In comparison, the sensitivity of computed tomography and magnetic resonance imaging was 4% and 15%, respectively, and the specificity was 100% for both procedures on the basis of a large number of negative interpretations. Logistic regression analysis revealed that immunoscintigraphy with 111In-capromab pendetide provided strong, independent evidence of the presence of lymph node metastases. Furthermore, the analysis indicated that certain combinations of PSA, Gleason score, and 111In-capromab pendetide were particularly effective at predicting the risk of nodal involvement. CONCLUSIONS: Immunoscintigraphy with 111In-capromab pendetide outperformed standard diagnostic imaging techniques in the detection of prostate cancer lymph node metastases and provided independent prognostic information that complemented PSA, Gleason score, and clinical stage.

Adenocarcinoma↗
PubMed1999

Haemostatic parameters related to lipids and adhesion molecules.

Several components of blood, e.g. lipids, coagulation and fibrinolytic factors, are thought to be important risk factors in cardiovascular diseases. The aim of this study was to correlate these risk factors and the soluble adhesion proteins, soluble P-selection (sP-selectin) and soluble vascular cell adhesion molecule (sVCAM-1), in healthy men and women as well as to unravel any effects of smoking. One hundred and forty-two fasting men (median age 36 years) including 39 smokers, and 124 women (median age 34 years) including 35 smokers, were tested between 0800 h and 1000 h. Fibrinogen correlated positively with white blood cells (WBC) (r = 0.25), prothrombin fragment 1.2 (F1.2) (r = 0.21), cholesterol (r = 0.27), beta-thromboglobulin (r = 0.29), Factor VII clotting activity (FVIIc) (r = 0.27) (all P < 0.0001), tissue plasminogen activator antigen (t-PAag) (r = 0.22, P < 0.0005), plasminogen activator inhibitor-1 antigen (PAI-1ag) (r= 0.20) and VCAM-1 (r= 0.19) (both P< 0.002). Cholesterol and triacylglycerol (TG) correlated positively with t-PA antigen (t-PAag) (r = 0.36 and r = 0.38), PAI-1 antigen (PAI-1ag) (r = 0.35 and r = 0.50), P-selectin (r = 0.26 and r = 0.27) (all P < 0.0001) and WBC (r = 0.17, P < 0.007 and r = 0.18, P < 0.004). Cholesterol correlated also with F1.2 (r = 0.29) and TG (r= 0.44) (P< 0.0001). In addition to cholesterol and TG, sP-selectin correlated postively with PAI-1ag (r= 0.39), t-PAag (r= 0.27) and WBC (r = 0.25) (all P < 0.0001). Comparing the various test parameters in men and women, it was found that women had significantly higher levels of F 1.2 and high-density lipoprotein-cholesterol than men, whereas men had higher levels of t-PAag, PAI-lag and P-selectin than women. Smoking was associated with a rise in several of the test parameters. It can be concluded that there are correlations between several risk factors. Of particular interest is the positive correlation between sP-selectin and a number of established risk factors of cardiovascular diseases.

Adult↗
PubMed1999

Lymphoscintigraphy and intraoperative lymphatic mapping of sentinel lymph nodes in melanoma patients.

Identification of sentinel lymph nodes (SLNs) using lymphoscintigraphy, the blue dye technique and intraoperative lymphatic mapping with a gamma-detecting probe has become the standard of care in diagnosing and treating melanoma. Numerous clinical studies have proven the reliability of predicting the histology of remaining lymph nodes in the lymphatic basin from the histologic evaluation of the SLNs. Technical and clinical factors presented in this paper have been shown to increase the accuracy of localization of SLNs. The nuclear medicine technologist shares a vital role in the radiopharmaceutical preparation and administration for preoperative lymphoscintigraphy and intraoperative lymphatic mapping in patients with melanoma.

Humans↗
PubMed1998

Multicenter radioimmunoscintigraphic evaluation of patients with prostate carcinoma using indium-111 capromab pendetide.

BACKGROUND: Optimum therapy for prostate carcinoma patients requires accurate staging, but computed tomography (CT) and magnetic resonance imaging (MRI) have limitations as methods for detecting soft tissue metastases. In this study, radioimmunoscintigraphy (RIS) was evaluated for its ability to identify sites of metastatic disease in lymph nodes. METHODS: RIS was evaluated in 51 prostate carcinoma patients at high risk for metastatic disease. An intravenous infusion of indium-111 capromab pendetide was given, followed by nuclear medicine imaging on two separate dates. Bilateral, open pelvic lymph node dissection was performed with additional exploration and biopsy of scan positive extraprostatic regions. Histologic evaluation of removed tissue confirmed the accuracy of RIS. In addition, results were compared with other standard methods for diagnosing patients prior to surgery. RESULTS: Nineteen patients (37%) had evidence of lymph node involvement with RIS. Fifteen of the 19 positive patients had pathologic evidence of cancer in the biopsied lymph nodes. Sensitivity, specificity, accuracy, and the positive predictive value for detection of extraprostatic disease were 75%, 86%, 81%, and 79%, respectively. CT, MRI, and ultrasound of the pelvis demonstrated a combined accuracy of only 48% in detecting lymph node disease. Twenty-five previously undetected sites were deemed positive with RIS. Fourteen of these were biopsy-proven tumor sites, seven were probable tumor sites, and four were assumed to be false-positive. CONCLUSIONS: RIS had an impact on patient management through its detection of occult disease in more than 50% of prostate carcinoma patients studied, and it provided information concerning the likelihood that lymph node metastases would be found during surgery.

Antibodies, Monoclonal↗
PubMed1998

Prostate cancer abdominal metastases detected with indium-111 capromab pendetide.

To provide appropriate therapy for prostate cancer, accurate staging of the patient's disease is essential. Determination of tumor size, location, periprostatic extension and metastatic disease in the skeleton and soft tissue are needed to stage properly. Current diagnostic modalities may lead to understaging in 40%-70% of prostate cancer. Detection of metastatic disease, both at the time of initial diagnosis and in patients with suspected local recurrence, can significantly alter the type of therapy given. Clinical studies using the (111)In radiolabeled immunoconjugate, MAb 7E11-C5.3-GYK-DTPA (capromab pendetide), have shown the superiority of radioimmunoscintigraphy over other diagnostic modalities in the detection of both primary and metastatic prostate cancer. Radioimmunoscintigraphy with capromab pendetide depends on expression of tumor-associated antigen rather than lesion size. Earlier detection of extraprostatic invasion and metastases by means of radioimmunoscintigraphy provides valuable information for treatment decisions. A case of metastatic prostate cancer in the abdomen of a patient without local disease, in which the extent of disease was confirmed at autopsy after sudden cardiac arrest, is presented.

Abdominal Neoplasms↗
PubMed1997

Technical considerations for acquiring and processing indium-111 capromab pendetide images.

A diagnostic quality 111In capromab pendetide study depends on parameters such as the quality control of the camera, thorough patient preparation, adequate imaging time and accurate computer processing. Comparisons of different patient preparation methods, imaging times, and camera and processing parameters were evaluated to provide high-quality 111In capromab pendetide images and to develop acquisition and processing parameters for 111In capromab pendetide imaging. SPECT images provide the best views of metastatic pelvic nodal involvement. Volume rendered three-dimensional registration best differentiates between normal vasculature and metastatic disease. Optimal acquisition parameters for delayed imaging included 128 x 128 matrix and 65 sec/step. The LFOV dual-head SPECT camera required only one SPECT acquisition that encompassed both the pelvis and abdomen. Planar and SPECT positioning was critical in evaluating questionable lymph nodes. In processing these images, the most diagnostic results were obtained with a three-dimensional low-pass post filter. The most effective patient preparation consisted of an oral cathartic, enema and catheterization when needed.

Antibodies, Monoclonal↗
PubMed1995

A novel biological effect of platelet factor 4 (PF4): enhancement of LPS-induced tissue factor activity in monocytes.

In a previous study we have shown that granulocytes enhance lipopolysaccharide (LPS)-induced tissue factor (TF) activity in monocytes in a platelet-dependent reaction. The present investigation was undertaken to examine the role of a platelet activation product, platelet factor 4 (PF4), in LPS-induced TF activity in monocytes. Platelet lysate supernatant, purified PF4, and the COOH-terminal tridecapeptide of PF4, termed PF4(58-70), enhanced LPS-induced TF activity in monocytes of whole blood dose dependently. A monoclonal antibody against P-selectin eliminated the enhancing effect of PF4(58-70) on LPS-induced TF activity in monocytes, and PF4(58-70) was shown to act synergistically with tumor necrosis factor alpha (TNF-alpha). However, PF4(58-70) did not enhance TNF-alpha secretion in LPS-stimulated whole blood. The major effect of PF4(58-70) was granulocyte dependent. Our results suggest that PF4 might play an important role in LPS-stimulated monocyte TF activity of whole blood.

Amino Acid Sequence↗
PubMed1995

Effect of marine oils supplementation on coagulation and cellular activation in whole blood.

A study was performed to explore the effects of supplemental intake of various marine oils known to be part of the Eskimo diet. Healthy men and women (134) were randomly selected to consume 15 mL/d of oil from blubber of seal, cod liver, seal/cod liver, blubber of Minke whale, or no oil for ten weeks. Total cholesterol was unchanged in the oil groups, whereas high density lipoprotein cholesterol increased 7% in the seal/cod liver oil (CLO) group (P < 0.05) and 11% in the whale oil group (P < 0.005). Triacylglycerol was significantly reduced in the CLO group only. The concentration of prothrombin fragment 1 + 2 was reduced 25% (P < 0.05) after whale oil supplementation. No change in fibrinogen or factor VIIc was detected. Tumor necrosis factor generation in lipopolysaccharide (LPS)-stimulated blood was 30% reduced after whale oil (P < 0.05), but was unaffected by intake of seal or CLO. The LPS-induced tissue factor activity in monocytes was reduced to a significant degree only in the seal/CLO group (34%) and whale oil group (35%) (P < 0.05). The most dramatic change in thromboxane B2 in LPS-stimulated blood was seen after whale oil intake with 44% reduction (P < 0.01). Supplementation of a regular diet with a combination of seal oil and CLO and especially with whale oil seems to have beneficial effects on several products thought to be associated with cardiovascular and thrombotic diseases.

Adolescent↗
PubMed1995

Somatostatin receptor imaging of neuroendocrine tumors with indium-111 pentetreotide (Octreoscan).

Somatostatin, a naturally occurring 14-amino acid peptide, can be thought of as an anti-growth hormone and functional down-regulator of sensitive tissue. Most neuroendocrine tumors seem to possess somatostatin receptors in sufficient abundance to allow successful scintigraphic imaging with radiolabeled somatostatin congeners. Several of these, including Indium-III-DTPA Pentetreotide (Octreoscan [Mallinckrodt Medical, St. Louis, MO]), which was approved for clinical use by the Food and Drug Administration in June 1994, have been of considerable value in scintigraphically identifying various neuroendocrine tumors. The Octreoscan compares favorably with other imaging modalities. The success of somatostatin receptor imaging in evaluating patients with suspected neuroendocrine tumors, including identifying otherwise radiographically occult lesions, has resulted in ranking somatostatin receptor imaging as the prime imaging procedure in patients with suspected neuroendocrine tumors at The Ohio State University.

Humans↗
PubMed1995

Indium-111-pentetreotide scanning versus conventional imaging techniques for the localization of gastrinoma.

BACKGROUND: The present study evaluates 111In-pentetreotide scanning as a method for detection of gastrinomas. Operative findings serve as the benchmark for comparison of the efficacy of 111In-pentetreotide versus conventional imaging studies. METHODS: Twelve patients (seven female and five male; age, 37 to 80 years) with histologic confirmation of gastrinoma underwent thin section dynamic computed tomography (CT) scanning and 111In-pentetreotide scanning. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 111In-pentetreotide and CT scanning are compared on the basis of tumor size and location. RESULTS: Thirty discrete foci of intrahepatic and extrahepatic tumors were detected at operation. CT scanning detected three of nine pancreaticoduodenal lesions, whereas eight of these nine extrahepatic primary tumors were imaged by 111In-pentetreotide scanning. No false-positive 111In-pentetreotide scans were noted. The sensitivity of CT scanning for detection of metastatic disease was 56% versus 94% for the 111In-pentetreotide scan. Successful CT imaging was highly dependent on tumor size. No tumor smaller than 1 cm was imaged by CT, whereas four of seven lesions greater than 1 cm were imaged by 111In-pentetreotide scintigraphy. The smallest gastrinoma imaged by 111In-pentetreotide scanning was a 4 mm duodenal tumor. CONCLUSIONS: 111In-pentetreotide scanning was superior to CT scanning for localizing gastrinomas. Further studies are required to determine whether 111In-pentetreotide scans will complement or replace traditional imaging methods.

Adult↗
PubMed1995

C3 is activated in hereditary angioedema, and C1/C1-inhibitor complexes rise during physical stress in untreated patients.

Seven patients with hereditary angioedema (HAE) were studied to understand further how physical exercise may induce attacks. The most pronounced differences between patients and controls, however, were independent of the controlled bicycle run (mean values in patients/ controls); C4(g/L): 0.12/0.28 (P = 0.0122); C4bc (AU/ml): 137.0/18.0 (P = 0.0002); C4d (mg/mL): 5.03/2.35 (P = 0.0004); C3bc (AU/ml): 8.4/6.3 (P = 0.0049); C3a (AU/ml): 11.1/5.6 (P = 0.0102). The ratio C4bc to C4 was 1141 versus 64. Consequently, a substantial part of the low amount of C4 left in HAE patients consists of activation products, and the authors show for the first time that a mild but significant activation of C3 occurs in HAE. The two HAE patients treated with danazol had values of C1-INH function and antigen, C4, and C2 in-between those of normal and untreated patients, and lower levels of split products from C4 and high molecular weight kininogen than untreated patients. As a result of the exercise, fibrinolysis increased significantly in both patients and controls, while C1/C1-INH complexes rose significantly only in the five HAE patients without treatment when compared to the seven controls (P = 0.0089). This study thus suggests that complement activation is enhanced in untreated HAE patients following physical stress.

Angioedema↗
PubMed1995

Factor VIIa in patients with C1-inhibitor deficiency.

In hereditary angioedema (HAE), normal C1-inhibitor (C1-INH) is low and the contact system activated. Recently, the findings of a tissue factor mutant selectively deficient in promoting the conversion of FVII to FVIIa, but with retained cofactor for FVIIa, made it possible to examine reliably the pre-existing content of FVIIa in HAE patients. This was of interest as FXIIa (mainly inhibited by C1-INH) is able to activate FVII directly. FVIIa in 21 remission HAE patients were within normal limits but nearly doubled as compared to their 23 normal siblings (p = 0.0017). Cold promoted activation of FVII (CPA) (common clot assay) was displayed in plasma of all 5 untreated patients (C1-INH function < 35%), but not in plasma of 2 patients treated prophylactically with danazol (C1-INH function about 40%). These results suggest that there is a minute, yet significant activation of FVII in patients with C1-INH deficiency.

Angioedema↗
PubMed1993

Granulocytes enhance LPS-induced tissue factor activity in monocytes via an interaction with platelets.

In the present study we have investigated the effect of platelets and granulocytes on bacterial lipopolysaccharide (LPS)-induced tissue factor (TF) activity in monocytes. Experiments were performed on freshly isolated cells resuspended in heparinized plasma and recombined with platelet-poor or platelet-rich plasma. In a platelet-dependent reaction the granulocytes enhanced LPS-induced TF activity by an average of 100%. The effect was dose dependent with regard to the number of both granulocytes and platelets, respectively. Granulocytes and/or platelets did not affect LPS-induced tumor necrosis factor (TNF) secretion from monocytes. Phorbol myristate acetate (PMA) per se was not able to induce TF activity in our system. In contrast, the agonist caused a substantial increase in TF activity induced by LPS. The effect was totally dependent on the presence of platelets and was shown to be due to stimulation of both granulocytes and monocytes (the activity rose from 30 +/- 7 to 83 +/- 12 mU/10(6) cells in the presence of platelets and from 69 +/- 8 to 143 +/- 22 mU/10(6) cells in the presence of platelets and granulocytes). Effects similar to those observed with PMA were obtained with physiological concentrations (10 ng/ml) of TNF. A combination of these two agonists gave no further amplification of LPS-induced TF activity compared with the effect of the agonists separately. Low concentrations of a monoclonal anti-CD15 antibody abolished the stimulatory effects of platelets and granulocytes. Furthermore, the anti-CD15 antibody neutralized the effect of TNF, whereas the PMA effect was reduced by almost 75%. These results were confirmed in a whole-blood system. The inhibitory effect of the antibody may be associated with CD15's role as a complementary ligand for PADGEM. Our study indicates that a close interaction between granulocytes, platelets, and monocytes is essential for optimal TF activity induced by LPS. It is hypothesized that the effect of granulocytes is related to their ability to activate platelets. We propose that upon activation granulocytes secrete a product that enhances the capacity of platelets to stimulate TF activity in monocytes.

Blood Platelets↗