James B. Hendricks

Alterations in circulating intercellular adhesion molecule-1 and L-selectin: Further evidence for chronic inflammation in ischemic heart disease

Atherosclerosis is increasingly thought to be a chronic inflammatory disease. Inflammation requires transmigration of leukocytes from the circulation to the tissues. Adhesion of leukocytes to endothelial calls is the initial event in an inflammatory response and is mediated by expression of several adhesion molecules. In this study we characterize the contribution of intercellular adhesion molecules (ICAM-1) and L-selectin in patients with different coronary artery disease syndromes. Serum concentrations of cICAM-1 and sL-selectin were measured by enzyme-linked immunosorbent assay in 31 patients with stable angina, 30 patients with unstable angina, 18 patients with acute myocardial infarction and 20 healthy subjects in a control group. All patients underwent coronary angiography. Mean (+/-SE) cICAM-1 levels were higher (p < 0.05) in patients with stable angina (249 +/- 6 ng/ml), unstable angina (260 +/- 16 ng/ml), or acute myocardial infarction (261 +/- 24 ng/ml) compared with those in subjects in the control group (171 +/- 11 ng/ml). In contrast, levels of sL-selectin were lower (p < 0.01) in patients with stable angina (1.2 +/- 0.1 microg/ml), unstable angina (1.1 +/- 0.6 microg/ml), or acute myocardial infarction (1.1 +/- 0.1 microg/ml) compared with those in subjects in the control group (1.8 +/- 0.1 microg/ml). No difference was found in cICAM-1 or sL-selectin levels among patients with stable angina, unstable angina, or acute myocardial infarction. No correlation was seen between cICAM-1 or sL-selectin levels and extent (or severity) of coronary artery disease or leukocyte count. L-selectin expression was observed to be depressed in patients with severe angina compared with that in members of the control group. To examine the mechanism of reduction in sL-selectin levels and L-selectin expression on leukocytes, leukocytes from the control group were stimulated in vitro. Stimulation of leukocytes resulted in a rapid downregulation of surface L-selectin expression, measured by flowcytometry, similar to the suppressed expression of L-selectin found on leukocytes from patients with coronary artery disease. In conclusion, altered cICAM-1 and sL-selectin levels in patients with coronary artery disease reflect the presence of a chronic inflammatory process. This inflammatory process results in downregulation of leukocyte expression of L-selectin and thus lower circulating sL-selectin levels.

Immunohistochemical evidence of aberrant bcl-2 protein expression in gastric epithelial dysplasia

Background. bcl‐2 protein encoded by the proto‐oncogene bcl‐2 confers to the cell a survival advantage by inhibiting apoptosis. Its aberrant expression has been reported in lymphomas and lung carcinoma. To determine if bcl‐2 plays a role in the gastric carcinogenic sequence, the authors studied bcl‐2 expression in gastric epithelial dysplasia (GED) and chronic atrophic gastritis with intestinal metaplasia (CAG‐IM).

Oxidized Low-Density Lipoproteins Facilitate Leukocyte Adhesion to Aortic Intima Without Affecting Endothelium-Dependent Relaxation Role of P-Selectin

Inflammatory cell deposition in atherosclerotic blood vessels has been thought to relate to loss of endothelium-derived nitric oxide (NO). To examine whether cell deposition correlates temporally with the loss of NO activity, rat aortic rings were incubated with buffer, native LDL (n-LDL), oxidized LDL (ox-LDL), or the endothelium-derived relaxing factor synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) for 2 hours, and vascular contractile response to norepinephrine and relaxant response to acetylcholine, thrombin, and calcium ionophore A23,187 were examined. Thereafter, the rings were exposed to biotin-fluorescein isothiocyanate-labeled fluorescent or unlabeled leukocytes for 30 minutes. Cell adhesion was quantitated by fluorescent microscopy as well as by scanning electron microscopy. Incubation with n-LDL or ox-LDL did not affect either the contractile or the relaxant response of rings. However, leukocyte adhesion increased markedly in all ox-LDL-treated rings but not in those treated with n-LDL. Thus, leukocyte adhesion occurred independent of NO activity. In keeping with this concept, pretreatment of rings with the NO precursor L-arginine failed to influence leukocyte adhesion to rings incubated with ox-LDL. Treatment of rings with L-NAME also resulted in adhesion of a large number of leukocytes. Furthermore, all rings treated with ox-LDL or L-NAME demonstrated marked expression of P-selectin leukocyte adhesion molecules, determined by immunohistochemistry. Pretreatment of rings with the P-selectin blocking antibody PB1.3 markedly decreased deposition of leukocytes in rings exposed to ox-LDL.(ABSTRACT TRUNCATED AT 250 WORDS)

Mesenchymal hamartoma of the liver. DNA flow cytometric analysis of eight cases

Background. Mesenchymal hamartoma of the liver is a rare lesion seen predominantly in childhood, which is believed to be either a developmental anomaly or reactive process. Because of recent reports of specific translocations involving chromosome 19 in mesenchymal hamartomas and certain ultrastructural and histologic features suggesting a relationship between mesenchymal hamartoma and undifferentiated (embryonal) sarcoma of the liver, some have speculated that mesenchymal hamartoma may be a neoplastic lesion with uncertain malignant potential.

Keratoacanthoma: A deficient squamous cell carcinoma? Study of bcl-2 expression

Ten keratoacanthomas with both proliferative and regressive histologic features along with 10 well‐differentiated squamous cell carcinomas were examined using immunohistochemistry for the expression of bcl‐2, a protooncogene recently recognized to be involved in protecting cells from undergoing apoptosis. The squamous cell carcinomas had a modest but diffuse staining pattern, while the proliferative keratoacanthomas stained only at the basal cells and only rare cells stained positively in the regressive keratoacanthomas. The degree and pattern of staining suggest a loss of bcl‐2 expression with tumor maturity in keratoacanthoma and a possible role in their ultimate involution.

Ki-67 expression in vulvar carcinoma

The proliferative activity of invasive squamous cell carcinoma of the vulva was examined using a Ki-67 equivalent monoclonal antibody (MIB1), which gives a strong immunoreaction in paraffin-embedded tissue. Quantitation of Ki-67 immunostaining was accomplished by image analysis. Ki-67 immunostaining revealed two general patterns of reactivity in vulvar tumors: (a) a diffuse distribution of Ki-67 positive nuclei within the tumor mass and (b) a localized distribution of Ki-67 positive nuclei staining predominantly basilar components of tumor aggregates. The distribution of localized and diffuse patterns did not differ significantly between various clinicopathologic categories (age, histologic type and grade, FIGO stage, and lymph node status). However, the survival times for patients with a diffuse Ki-67 labelling pattern tended to be shorter than those for patients with a localized pattern. Survival curves based on the median positive nuclear area (PNA) calculated by image analysis did not differ significantly. Thus, the pattern of Ki-67 immunostaining, rather than the percentage of PNA, may have prognostic significance in vulvar squamous cell carcinoma.

Proliferating trichilemmal cyst. Report of four cases, two with nondiploid DNA content and increased proliferation index.

Proliferating trichilemmal cyst (PTC) is an uncommon tumor that usually arises on the scalp of elderly women. Its biologic nature is that of a benign lesion with occasional local recurrences. PTC can be confused both grossly and microscopically with squamous cell carcinoma and malignant PTC. Distinction between these lesions has historically been made on a histologic basis. We present four cases of PTC. Histologically, the lesions consisted of lobules of basaloid cells admixed with larger pale-staining cells with abrupt trichilemmal type of keratinization and peripheral palisading embedded in a fibrous stroma. Flow cytometry performed on nuclear extracts of the lesions revealed two of the four lesions to have nondiploid DNA content. Proliferation index, measured by immunohisto-chemical staining with Ki-67 monoclonal antibody along with mitotic rate count, was higher in the two nondiploid lesions as compared with their diploid counterparts. The results raise the question of the significance of aneuploidy and increased proliferation indices in otherwise benign PTC.

Fibro-osseous pseudotumor of the digit : a comparison to myositis ossificans by light microscopy and immunohistochemical methods

Fibro‐osseous pseudotumor of the digit is an unusual cutaneous process characterized histologically by a fibroblastic proliferation admixed with reactive/metaplastic osteoid formation. The osteoid formation can be florid and immature, mimicking the appearance of malignant osteoid‐forming neoplasms. Fibro‐osseous pseudotumor of the digit has histologic and clinical features in common with myositis ossificans. This has led many to consider the two to be synonymous. We studied three cases of fibro‐osseous pseudotumor, compared to five cases of myositis ossificans, using routine light microscopy and a battery of immunohistochemical stains.

Quantitative Histology by Laser Scanning Cytometry

Abstract The Laser Scanning Cytometer (LSC) is a relatively new class of instrument that combines features of both flow and image cytometry. The LSC is capable of measuring multicolor fluorescence, light scatter, and the location of cells fixed to a glass slide. It is capable of automatically measuring a large number of cells with data displayed in real time. In addition, cell location is recorded so that cells of interest can be relocated for morphological examination and classification. The LSC is capable of measuring a wide variety of sample types, including thin preps, cytospins, touch imprints, and tissue sections. In this brief review paper, the mechanics of laser scanning cytometry are examined along with potential applications to conventional histopathology. (The J Histotechnol 24:59, 2001) Submitted: September 9, 2000; Accepted with revisions: December 29, 2000

Retroviral Producer Cells Cause Sarcoma in Severe Combined Immunodeficiency Mice.

Direct in situ introduction of retroviral producer cells might provide a form of treatment for localized tumors. A possible undesirable consequence of this treatment could be uncontrolled proliferation of the injected producer cells. To test this possibility, severe combined immunodeficiencies (SCID) mice were reconstituted with human peripheral blood lymphocytes which were marked with a retroviral vector using a coculture method. Although specific measures were taken to remove the possible contaminating producer cells, a high percentage of mice developed fibrosarcoma 2-6 weeks after reconstitution. We hypothesized that tumors arose from a small number of contaminating producer cells in the inoculum. Tumor cells were consistently DNA tetraploid, a characteristic of the producer cell line. DNA extracted from tumor tissue was found to contain the gene (neomycin phosphotransferase) used to mark the producer cell line. Furthermore, SCID mice injected with 1 x 10(4) producer cells developed tumors with analogous characteristics. This report indicates that the retroviral producer cell line is tumorigenic in immune-deficient animals. Copyright 1995 S. Karger AG, Basel