Expression Of Various Antigens Research Articles

Transition from Morphocytochemical Diagnosis to Immunophenotypic Diagnosis of Acute Leukemia: A Flow Cytometry Experience from Southern Odisha

ABSTRACT Background: In today’s generation of targeted therapy, traditional reporting of acute leukemia by morphology using the FAB system of classification has limited uses due to a lack of standardization and use in risk stratification. Immunophenotyping by flow cytometry has gained popularity due to its influence on the treatment and prognosis of the disease. The present study evaluates the judicious application of flow cytometry as an adjunct to morphocytochemical assessment in all newly diagnosed cases of acute leukemia in Southern Odisha. Materials and Methods: A total of 61 cases were subjected to complete blood count analysis, peripheral smear examination, bone marrow study, cytochemistry, and those suspected of leukemia underwent flow cytometry analysis using BD FACS CANTO II as per manufacturer’s instructions. Results: Out of 61 cases of acute leukemia diagnosed, 35 were acute lymphoblastic leukemia, and 24 were acute myeloid leukemia. There was 96.7% correlation between diagnosis by cytomorphology and flow cytometry. Seven cases showed aberrant expression of various antigens. Two cases of acute leukemia on cytomorphology were diagnosed as hematogones and the other as reactive lymphocytosis on flow cytometry. Conclusion: Although morphologic FAB diagnosis is still widely used to classify acute leukemia, flow cytometry has more specificity and should be used as an adjunct to morphology. Along with subclassification of leukemia, flow cytometry can also detect the possibility of an associated genetic abnormality.

Alphaviruses in Immunotherapy and Anticancer Therapy.

Alphaviruses have been engineered as expression vectors for vaccine development and gene therapy. Due to the feature of RNA self-replication, alphaviruses can provide exceptional direct cytoplasmic expression of transgenes based on the delivery of recombinant particles, naked or nanoparticle-encapsulated RNA or plasmid-based DNA replicons. Alphavirus vectors have been utilized for the expression of various antigens targeting different types of cancers, and cytotoxic and antitumor genes. The most common alphavirus vectors are based on the Semliki Forest virus, Sindbis virus and Venezuelan equine encephalitis virus, but the oncolytic M1 alphavirus has also been used. Delivery of immunostimulatory cytokine genes has been the basis for immunotherapy demonstrating efficacy in different animal tumor models for brain, breast, cervical, colon, lung, ovarian, pancreatic, prostate and skin cancers. Typically, therapeutic effects including tumor regression, tumor eradication and complete cure as well as protection against tumor challenges have been observed. Alphavirus vectors have also been subjected to clinical evaluations. For example, therapeutic responses in all cervical cancer patients treated with an alphavirus vector expressing the human papilloma virus E6 and E7 envelope proteins have been achieved.

Critical evaluation of the utility of pre- and post-therapy immunophenotypes in assessment of measurable residual disease in B-ALL.

Measurable residual disease (MRD) is an important parameter to predict outcome in B-cell acute lymphoblastic leukemia (B-ALL). Two different approaches have been used for the assessment of MRD by multiparametric flow cytometry that include the "Leukemia Associated Aberrant Immunophenotype (LAIP)" and "Difference from Normal (DFN)" approach. In this retrospective study, we analyzed 539 samples obtained from 281 patients of which 258 were paired samples and the remaining 23 samples were from post-induction time point only, to explore the utility of baseline immunophenotype (IPT) for MRD assessment. Single-tube 10-color panel was used both at diagnosis and MRD time points. Out of 281 patients, 31.67% (n = 89) were positive and 68.32% (n = 192) were negative for MRD. Among 258 paired diagnostic and follow-up samples, baseline IPT was required in only 9.31% (24/258) cases which included cases with hematogone pattern and isolated dim to negative CD10 expression patterns. Comparison of baseline IPT with post-induction MRD positive samples showed a change in expression of at least one antigen in 94.04% cases. Although the immunophenotypic change in expression of various antigens is frequent in post-induction samples of B-ALL, it does not adversely impact the MRD assessment. In conclusion, the baseline IPT is required in less than 10% of B-ALL, specifically those with hematogone pattern and/or dim to negative expression of CD10. Hence, a combination of DFN and LAIP approach is recommended for reliable MRD assessment.

Post-translational modifications of α-synuclein contribute to neurodegeneration in the colon of elderly individuals.

Synucleinopathies and abnormalities in the nerves of the enteric nervous system are hypothesized to be involved in age-associated motility disorders. The aim of the present study was to investigate the expression of various antigens, including α-synuclein (Syn) and its post-translational modified forms, in the human colon at various ages. In addition, the study aimed to correlate the expression of Syn with neurodegeneration. Immunohistochemistry was used to detect the expression of neurofilament (NF), Syn, as well as its nitrated (N) form in the healthy colonic tissue of 12 young (34.08±5.12 years), 10 middle-aged (51.80±3.52 years), and 11 elderly (75.82±7.70 years) individuals. To the best of our knowledge, the current study is the first to demonstrate the presence of N-Syn in the colonic tissue. N-Syn was identified in the upper layer of the mucosa and submucosa layer. Furthermore, Syn (wild-type) was present in the mucosa and submucosa. The number of NF-positive neurons in the submucosal layer declined significantly with age (P<0.01). In addition, Syn and N-Syn significantly increased during aging (P<0.01). Furthermore, a negative correlation was identified between neuron number and synucleinopathies, indicating the abnormal accumulation of both wild-type Syn and N-Syn in the mucosa, submucosa, muscle layer and myenteric plexus. The present study demonstrates that the Syn pathology may be linked to colic neuronal degeneration during normal aging, and this link may cause functional deficits.

Antigen Expression on Blast Cells and Hematological Parameters at Presentation in Acute Lymphoblastic Leukemia Patients.

To analyze the expression of various antigens on the leukemic blasts and to determine the hematological parameters, in Acute Lymphoblastic Leukemia (ALL) patients at presentation. Observational study. King Edward Medical University, Lahore and Hameed Latif Hospital, Lahore, from February 2013 to March 2014. A total of 50 newly diagnosed and untreated patients of ALL were selected from Mayo Hospital and Hameed Latif Hospital. These patients included both genders and all age groups. Hemoglobin, total leukocyte count and platelet count were determined on hematology analyser-Sysmex-Kx-2I. Blast cell percentage was estimated on Giemsa stained blood smears. Immunophenotyping was done on bone marrow samples by 5 colour flowcytometery on Beckman Coulter Navious Flowcytometer. An acute leukemia panel of 23 antibodies was used. The data was entered and analyzed in SPSS version 22. Of the 50 ALL patients, 36 (72%) were B-ALL and 14 (28%) T-ALL. There were 18 (36%) children and 32 (64%) adults. T-ALL included 22% of the childhood and 31% of the adult cases. Immunophenotypic analysis showed that CD19, CD79a and CD20 were B-lineage specific markers whereas cCD3, CD3 and CD5 were T-lineage specific. CD10 was the most sensitive marker for B-ALL and CD7 was the most sensitive marker of T-ALL. TdT was expressed in 92% B-ALL and 71% T-ALL cases, CD34 in 58% and 43% cases and CD45 in 83% and 100% respectively. High leukocyte count (> 50 x 109/L) was present in 58% cases. Hemoglobin was < 10 g/dl in 74% patients and platelet count was below 20 x 109/Lin 12% patients. Leukocyte count, hemoglobin, platelet count and blast cell % did not show a significant difference in the two ALL immunotypes. The frequency of T-ALL is higher in childhood as well as adult ALL in our population compared to the Western literature. Antigenic expression of the blast cells also shows some interesting differences. A large number of our patients present with high leukocyte count which is a known factor associated with poor prognosis.

The immunocytochemical expression of various ECM antigens: a useful tool in the evaluation of biocompatibility of implant biomaterials

The aim of the present work was to investigate the biocompatibility in vitro of biomedical biomaterials employed in stomathology, in order to assess useful biological parameters, i.e. the correlation between cell proliferation rates and the expression of various antigens of the extracellular matrix (ECM), as well as to obtain useful information for the subsequent “in vivo” investigations. While in the study of bio- compatibility of dental implants many reports have been performed regarding the aspects of osteointegration processes, few studies have examined the relationships between soft tissues and biomaterials [2]. In particular, we would study the relation- ship between cell proliferation rates of cultured fibroblasts and the immunocyto- chemical expression of molecules involved in cell adhesion mechanisms to ECM, i.e. fibronectin, chondroitin sulfate and alpha5 beta1 integrin. We observed that cell proliferation was related in particular to the expression degree of fibronectin. As far as the different dental implant surfaces were concerned, we found that fibronectin exhibit- ed a greater immunocytochemical expression in fibroblasts cultures in the presence of smooth surfaces correlated with higher fibroblast proliferation rates, suggesting that smooth surfaces could allow a better adhesion of cells of the soft oral tissues, i.e. gingival connective tissue. We think these results could be interesting, since the integration of implant dental materials requires not only the best osteointegration, but also an optimal adhesion of gingival soft tissues to the apical part of the same dental implant. These findings could also suggest that dental implant surfaces should be manufactured to obtain the best osteointegration in its deeper part, together with the best fibroblast adhesion in its apical portion.

Ex Vivo Derived Primary Melanoma Cells: Implications for Immunotherapeutic Vaccines

Transformation of the pigment producing melanocytes into melanoma is a complex multi-step process involving the enhanced expression of various antigens considered as immunotherapeutic targets. Significant progress in melanoma research has been made over the years and has resulted in the identification of various antigens over expressed in melanoma as well as advances in immunotherapeutic treatments, which focus on modulating the immune systems response to melanoma. Despite these advances, incidences of melanoma are still on the rise thus warranting additional research in identifying new therapeutic treatments. Our focus is on developing a multivalent immunotherapeutic vaccine that targets various melanoma associated antigens. The approach focuses on the use of five primary patient derived melanoma cells (MEL-2, MEL-V, 3MM, KFM, and GLM-2, which have been characterized in this study. These cells express differential amounts of various melanoma associated antigens such as MART-1, gp100 (Pmel17), MAGE-A1 and tyrosinase as well a cell surface antigens essential for melanoma cell metastasis, such as CD146 and CD71. In addition these cells display differential in vitro migratory and invasive properties as well as have the ability to form solid tumors when implanted into BALB/c nude mice. The retention of the innate phenotype of these primary patient derived cells together with the expression of a multitude repertoire of melanoma associated antigens offers a novel opportunity to target melanoma so as to avoid immune evasion.

Identification of Cell Surface Antigen Expression in Canine Hepatocellular Carcinoma Cell Lines

The characteristics of surface antigens in canine hepatocellular carcinoma (cHCC) have not been clarified. The objective of this study was to investigate surface antigens, which are considered as stem/progenitor or cancer cell markers, in cHCC cell lines. Expression of various antigens including CD29, CD34, CD44, CD90, CD133 and Dlk-1 was assessed in four cHCC cell lines by flow cytometry. CD44, CD133 and Dlk-1 expression was detectable in all cell lines, and three cell lines expressed CD29. These results indicate that CD29, CD44, CD133 and Dlk-1 have potential as suitable markers in cHCC identification, suggesting that these findings will contribute to the establishment of an early diagnostic tool for the identification of hepatocellular maturation processes.

[Rosai-Dorfman disease: clinicopathologic, immunohistochemical and etiologic study of 16 cases].

To study the clinicopathologic features of Rosai-Dorfman disease (RDD), expression of various antigens, human herpes virus type 8 (HHV8), human papillomavirus (HPV)-DNA and Epstein-Barr virus (EBV)-mRNA, and compare the findings with those in the literature. The clinicopathologic findings of 16 Rosai-Dorfman disease cases were retrospectively reviewed. Immunohistochemical study for S-100 protein, CD68 (PG-M1), CD163, CD21, CD1a, CD20, CD45RO, CD4, CD8, M-CSF and HHV8 was carried out in 9 of the 16 cases. In-situ hybridization for EBV-mRNA and HPV-DNA was also performed. The male-to-female ratio of the patients was 4.33:1. Amongst the 16 cases studied, 62.5% (10/16) presented nodal RDD, with cervical lymph node predominantly involved. Half of these cases had affected lymph nodes in more than one anatomic site. Extranodal RDD represented 37.5% (6/16) of the cases. The relapse rate of extranodal RDD was higher than that of nodal RDD. Histologically, nodal RDD was characterized by dilated sinuses filled with large polygonal histiocytes which contained lymphocytes and plasma cells. For extranodal lesions, various degrees of stromal fibrosis were seen in association with mixed inflammatory cells (especially plasma cells). The large polygonal histiocytes varied in number and were distributed in clusters or patches. Immunohistochemical study showed that the abnormal histiocytes were strongly positive for S-100 protein. They also expressed CD68, CD163 and M-CSF, but were negative for CD1a, CD21 and HHV8. The lymphocytes in cytoplasm of these histiocytes were positive for both T and B cell markers (with T cell predominance, including a mixture of CD4- and CD8-positive cells). HPV-DNA and EBV-mRNA were not detected by in-situ hybridization. To date, 62 cases of RDD have been reported in mainland China, including 34 cases of nodal RDD and 18 cases of extranodal RDD. The remaining 10 cases involved both lymph nodes and extranodal sites. Compared with overseas reports, RDD occurring in China tended to affect older patients and with slight male predilection. Rosai-Dorfman disease is relatively rare in China. Pathologic diagnosis of extranodal RDD may be difficult. The demographic data of RDD in China, including age and sex of patients, are different from those in the literature.

局所多発性Ｅｐｉｄｅｒｍｏｌｙｔｉｃ　Ａｃａｎｔｈｏｍａ

A 68-year-old man presented with more than 30 brownish papules up to 2 mm in diameter on the penis. Histologically, there were marked hyperkeratosis and acanthosis with prominent granular degeneration. The eruption was diagnosed as localized multiple epidermolytic acanthoma. We immunohistochemically studied the expression of various antigens in the specimen along with epidermal nevus with granular degeneration, exhibiting bullous congenital icthyosiform erythroderma, and normal skin. Cytokeratin (CK) 10 and CK1 were not homogeneously distributed in the disordered granular layer, in comparison with the normal granular layer. CK17 was partly stained in the granular layer of the localized multiple epidermolytic acanthoma, but not in the other two diseases, carcinoembryonic antigen was expressed not only in the disordered granular layer but also in the adjacent normal-appearing granular layer. Therefore, we considered that the epidermis surrounding the papules had the same abnormality as the lesional skin.

Gene transfer and expression of enhanced green fluorescent protein in variant HT-29c cells.

To study the expression of enhanced green fluorescent protein (EGFP) gene in retrovirally transduced variant HT-29 cells. The retroviral vector prkat EGFP/neo was constructed and transfected into the 293T cell using a standard calcium phosphate precipitation method. HT-29c cells (selected from HT-29 cells) were transduced by a retroviral vector encoding the GEFP gene. The fluorescence intensity of colorectal carcinoma HT-29c cells after transduced with the EGFP bearing retrovirus was visualized using fluorescence microscope and fluorescence activated cell sorter (FACS) analysis. Multiple biological behaviors of transduced cells such as the proliferating potential and the expression of various antigens were comparatively analyzed between untransduced and transduced cells in vitro. EGFP expression of the fresh tumor tissue was assessed in vivo. After transduced, HT-29c cells displayed a stable and long-term EGFP expression under the nonselective conditions in vitro. After cells were successively cultured to passage 50 in vitro, EGFP expression was still at a high level. Their biological behaviors, such as expression of tumor antigens, proliferation rate and aggregation capability were not different compared to untransduced parental cells in vitro. In subcutaneous tumors, EGFP was stable and highly expressed. An EGFP expressing retroviral vector was used to transduce HT-29c cells. The transduced cells show a stable and long-term EGFP expression in vitro and in vivo. These cells with EGFP are a valuable tool for in vivo research of tumor metastatic spread.

Anti-Endothelial Cell Antibodies (AECA) in Systemic Sclerosis - Increased Sensitivity using Different Endothelial Cell Substrates and Association with Other Autoantibodies

Objective: One of the main features of systemic sclerosis (SSc) is vascular damage, the mechanism of which is not understood. In the present study we examined whether screening of SSc patients for different anti-endothelial cells antibodies (AECA) of various origins increase the sensitivity of AECA detection in SSc patients. Secondary aim was an attempt to correlate AECA with other common autoantibodies.Materials & methods: 478 SSc patients were studied for the presence AECA. anti-cardiolipin (aCL), anti-dsDNA, anti-heparin (AHA), anti-pyruvate dehydrogenase (PDH) and anti-PDC-E2 autoantibodies. AECA levels were determined using human umbilical vein EC (HUVEC), bone marrow EC (BMEC), EC hybridoma (EA.hy 926) and Kaposi sarcoma EC (KS).Results: Positive AECA were found in 49.5% of SSc patients (27.1% HUVEC: 34.3% BMEC; 26.3% EaHy 926 and 22.7% KS). The highest percent reactivity of AECA was obtained using microvascular BMEC. When combining BMEC and either other cell lines the reactivity ranged from 41.4% to 46%. A significant association between AECA on the one hand and AHA (p<0.001) and anti-PDH (p<0.05) on the other was seen. Cross-reactivity with anti-PDC-E2 was excluded by inhibition tests, but AHA and anti-PDH may be part of the spectrum of AECA.Conclusions: Since false-negative AECA may result from lack of expression of various antigens on a specific EC, analysis of AECA in SSc patients requires using several EC types, including microvascular EC.

Direct IFNluence of interferon-γ on proliferation and cell-surface antigen expression of non-small cell lung cancer cells

In order to clarify the anti-tumor activity of IFN-γ, we investigated the direct IFNluence of IFN-γ on both the growth and cell-surface antigen expression of tumor cells. In the present study, four human lung cancer cell lines were used; two squamous cell lines (QG-56, QG-95) and two adenocarcinoma cell lines (PC-9, PC-12). In all four tumor cell lines, mutations were detected in exon 7 of the p53 gene by a PCR-FSSCP analysis. The proliferation of QG-56 or QG-95 was inhibited by IFN-γ in a dose-dependent manner with about 70% inhibition at 1000 JRU/ml while that of PC-9 was slightly inhibited with maximally 25% inhibition at 1000 JRU/ml. The growth of PC-12 was not inhibited at all. In QG-56, QG-95 and PC-9, the fraction of cells in G1 phase increased while the fractions of cells in both S and G2/M phases decreased after exposure to IFN-γ (200 JRU/ml) for 72 h. The growth inhibition by long-term exposure to IFN-γ was irreversible in QG-56. After culture in the presence of IFN-γ (200 JRU/ml) for 14–16 days, tumor cells were examined for expression of various antigens, including HLA-class I, HLA-class II, and CEA. In all cell lines but PC-12, 100% of cells expressed HLA-class I after incubation with IFN-γ. Both HLA-class II and CEA were also induced in those cell lines. The proportion of HLA-class II-positive cells or that of CEA-positive cells varied among the cell lines. Of the three antigens, the degree of HLA-class II expression paralleled that of growth inhibition by IFN-γ treatment. These results suggested that in various function of IFN-γ against tumor cells, the anti-proliferative effect might be closely linked with the induction of HLA-class II probably through a similar posttranscriptional process, independent of the function of p53 gene.

Flow cytometric quantitation of immunofluorescence intensity: problems and perspectives. European Working Group on Clinical Cell Analysis.

Quantitation of immunofluorescence intensity serves to estimate the number of defined molecules expressed on or in cells. Clinical applications of this diagnostic tool are increasing, e.g., aberrant expression of various antigens (Ag) by leukemic blasts or lymphoma cells, intensity of CD38 expression by CD8+ T-lymphocytes to monitor activation status, and intensity of CD62P to detect platelet activation. In this report we discuss the quality-control measures required for quantitation of fluorescence intensity, and we review seven concepts that have been developed to quantify fluorescence intensity during the past 15 years. Initial work addressed the conversion of logarithmic channel numbers into units of relative fluorescence. The design and use of calibration beads labeled with predefined amounts of dye allowed instrument-independent expression of fluorescence intensity in units of molecules of equivalent soluble fluorochrome (MESF). This method was refined by the combined use of such standards with monoclonal antibodies (mAb) conjugated 1:1 with phycoerythrin (PE), allowing translation of fluorescence intensity into numbers of antibodies bound per cell. Alternatively, the use of 1:1 PE-conjugated mAb under the assumption that CD4+ lymphocytes reproducibly bind 50,000 CD4 mAb molecules was proposed to convert units of relative fluorescence intensity into units of antibodies bound per cell. The use of antibody-binding capacity as a surrogate marker for quantification of Ag expression was addressed more directly by the development of antibody-binding standards. The quantitative indirect immunofluorescence assay is based on beads labeled with various amounts of CD5 mAb that calibrate the binding of the secondary antibody in units of antibody-binding capacity. Alternatively, goat anti-mouse-labeled calibration beads have been developed. Published results obtained with the latter calibrators showed an unexpected inaccuracy. The different ways in which calibrators and cells under study bind mAb (i.e., Fab mediated versus Fc mediated) may have contributed to this variation. Recently, the use of stabilized cell populations expressing Ag in a specified range of concentrations has been proposed as an Ag-specific calibration system of mAb binding. We identify several issues on the level of instrumentation, reagents, and cells under study that should be solved to allow standardization of quantitative assessments of immunofluorescence intensity.

VLA2 integrin expression in breast carcinomas evaluated by automated and quantitative immunohistochemistry.

VLA2 is thought to be involved in the metastatic process in malignant tumours, in particular in carcinomatous cell adhesion to vessel basement membrane. VLA2 expression was immunohistochemically investigated in 204 breast carcinomas. Frozen tissue sections were probed with monoclonal anti-VLA2 using automated (Ventana ES 320 System) and quantitative (SAMBA 2005 image processor) immunoperoxidase. A positive anti-VLA2 immunoreaction was observed in 48 tumours (23.5%), within epithelial carcinomatous cells. The VLA2-positive surface in tumours varied from 3% to 20% (mean 8.75, S.D. 7.17) and was correlated with histoprognostic indicators and tumour expression of various antigens detected using the same method as that for VLA2. The results show that VLA2 immunoexpression was independent of the tumour size, grade, type and aneuploidy, and of the nodal status. VLA2 significantly correlated with ELAM, VCAM, VLA3 and P-glycoprotein (P-gp) (P < 0.01) and inversely correlated with cathepsin D (P < 0.001), but was independent of Ki67/MIB1, p53, bcl-2, c-erbB-2, E cadherin, CD44v, CD31, oestrogen and progesterone receptors' (ER, PR) antigenic sites and pS2. The exact role, if any, of VLA2 in tumour cell dissemination remains to be elucidated and the clinical relevance of VLA2 immunodetection in breast carcinomas requires further investigation of the correlation between VLA2 immunocytochemical expression and patients' outcome and response to chemotherapy.

ELAM selectin expression in breast carcinomas detected by automated and quantitative immunohistochemical assays.

ELAM is an E-Selectin adhesion molecule involved in the inflammatory process but it is also thought to potentially participate in the development of blood borne metastases, by facilitating tumour cell adhesion to vessels wall. ELAM expression in tumours was immunohistochemically investigated in 203 breast carcinomas. Frozen tissue sections were probed with monoclonal anti ELAM (Clone 1.2B6) using automated and quantitative immunoperoxidase systems. A positive anti-ELAM immunoreaction was observed in 113 tumours (57%). The mean surface of positive tumours varied from 3% to 50% (mean = 11.75%, SD = 8.7) and was correlated with histoprognostic indicators and tumour expression of various antigens detected according to the same method as ELAM. The results showed that ELAM immunoexpression was independent of the tumour size, grade and type and of the nodal status but significantly increased parallel to patients' age (p<0. 01). ELAM expression was independent of Ki-67/MIB1, anti-P53 and anti-Bcl2, anti-CD44v, anti-c-erbB-2, anti-CD31, anti-RE/RP, anti-PS2, and anti-VLA3 immunoreactions. But ELAM expression correlated with that of the VCAM vascular cell adhesion molecule (p=0.0004), VLA2 (p<0.0001), P-glycoprotein (p=0.025), and of Cathepsin D to a lower degree (p=0.06) and inversely correlated with E-cadherin (p=0.03). The results suggest that endothelial cell activation is independent of tumour cell proliferative activity and of stromal angiogenesis and that the precise role and regulation of ELAM in tumours remains to be elucidated. Also the clinical relevance of ELAM immunohistochemical expression requires further investigation and correlation with patients' follow-up.

Effects of 1 alpha,25-dihydroxyvitamin D3 and cytokines on the expression of MHC antigens, complement receptors and other antigens on human blood monocytes and U937 cells: role in cell differentiation, activation and phagocytosis.

The effect of calcitriol/1 alpha,25-dihydroxyvitamin D3, alone and in combination with cytokines, on the expression of various antigens (Ag) on human peripheral blood monocytes and U937 cells was studied by flow cytometry. Both constitutive and interferon-gamma (IFN-gamma), interleukin-4 (IL-4), IL-6 and tumour necrosis factor-alpha (TNF-alpha)-induced human leucocyte antigen (HLA)-DR, HLA-DP and HLA-DQ Ag expression on monocytes was significantly down-regulated by calcitriol, IL-10 and transforming growth factor-beta (TGF-beta). The effects of calcitriol were concentration dependent and reached maximal inhibitory levels after 3-5 days. Modulation of HLA-DR by calcitriol and IFN-gamma at the protein level correlated with the amount of mRNA specific for the HLA-DR alpha-chain, as judged by Northern blot analysis. The basal as well as IL-4, IL-6, IFN-gamma, TNF-alpha and TGF-beta-driven levels of HLA-ABC Ag were significantly diminished by calcitriol. On U937 cells calcitriol markedly induced CD11a and CD11b expression and weakly up-regulated CD11c whereas on monocytes, constitutive CD11a, CD11b and CD11c expression was significantly down-regulated by calcitriol. The expression of CD14 Ag was strongly induced on U937 cells but only modestly on monocytes. Both the basal level of CD71 and IL-4, IFN-gamma or TNF-alpha-driven expression was diminished on calcitriol-treated U937 cells. In addition, calcitriol suppressed the expression of CD71 Ag on monocytes. The ability of monocytes to phagocytize opsonized Escherichia coli was diminished by calcitriol. Our results demonstrate that calcitriol, alone or in combination with cytokines, modulates expression of MHC, CD11b, CD11c, CD14 and CD71 Ag on both monocytes and U937 cells, and impairs the phagocytic property of monocytes.

A technique for retrieving antigens in formalin-fixed, routinely acid-decalcified, celloidin-embedded human temporal bone sections for immunohistochemistry.

The application of immunohistochemistry to routinely decalcified, celloidin-embedded human temporal bone sections has been hampered because of antigen loss during processing of the specimens. To our knowledge, there has been no published report to date describing immunohistochemical staining of such tissues suitable for examination by light microscopy. Here we report a novel antigen retrieval technique which can be successfully used to stain a variety of antigens in routinely formalin-fixed, trichloroacetic acid-decalcified, celloidin-embedded human temporal bone sections. The new procedure reported here for decalcified human temporal bone tissues simply requires immersing slides for 30 min at room temperature in an antigen retrieval solution. A total of 60 decalcified, celloidin-embedded human temporal bone tissues were tested with monoclonal antibodies (MAb) to 15 different antigens. Of these, 12 MAb showed definite positive staining, while three were negative. This technique may prove very useful in studying the expression of various antigens by immunohistochemistry in formalin-fixed, acid-decalcified, celloidin-embedded tissues.

Immunophenotyping and Functional Analysis of Purified Human Uterine Mast Cells

Human mast cells have been purified from uterine tissues, and their surface marker profile and function have been evaluated as part of ongoing studies of mast cell heterogeneity. Using a panel of antibodies, purified uterine mast cells (UMC; 81% +/- 7% purity, n = 10) were analyzed by immunofluorescence and flow cytometry for surface expression of various antigens. Consistent with previous analyses of mast cells from other tissues, UMC expressed HLA class I, IgE, c-kit receptor, CD9, CD33, CD43, CD45, and CD54, while CD11a, CD11b, CD14, CD16, CD23, and CD64 were not detected. Unlike other mast cells, UMC expressed CD11c/CD18 (p150,95) and CD32 (Fc gamma RII). Additional antigens not previously studied on mast cells included the selectin LECAM-1 (Leu-8) and several beta 1 and beta 3 integrins; expression of very late activation antigen-4 (VLA-4) (CD49d/CD29), VLA-5 (CD49e/CD29), and the vitronectin receptor (CD51/CD61) was seen. Functional studies showed that treatment of human umbilical vein endothelial cells with interleukin-1 (5 ng/mL for 4 hours) resulted in a twofold to threefold increase in adhesiveness for UMC. Purification procedures did not alter histamine release responses to anti-IgE or the calcium ionophore A23187, and treatment of UMC with an anti-CD32 monoclonal antibody (IV.3) did not induce histamine release or alter anti-IgE-induced release. These data suggest that UMC may possess unique phenotypic characteristics, and support the concept of mast cell heterogeneity.

Immunophenotyping and functional analysis of purified human uterine mast cells

Human mast cells have been purified from uterine tissues, and their surface marker profile and function have been evaluated as part of ongoing studies of mast cell heterogeneity. Using a panel of antibodies, purified uterine mast cells (UMC; 81% +/- 7% purity, n = 10) were analyzed by immunofluorescence and flow cytometry for surface expression of various antigens. Consistent with previous analyses of mast cells from other tissues, UMC expressed HLA class I, IgE, c-kit receptor, CD9, CD33, CD43, CD45, and CD54, while CD11a, CD11b, CD14, CD16, CD23, and CD64 were not detected. Unlike other mast cells, UMC expressed CD11c/CD18 (p150,95) and CD32 (Fc gamma RII). Additional antigens not previously studied on mast cells included the selectin LECAM-1 (Leu-8) and several beta 1 and beta 3 integrins; expression of very late activation antigen-4 (VLA-4) (CD49d/CD29), VLA-5 (CD49e/CD29), and the vitronectin receptor (CD51/CD61) was seen. Functional studies showed that treatment of human umbilical vein endothelial cells with interleukin-1 (5 ng/mL for 4 hours) resulted in a twofold to threefold increase in adhesiveness for UMC. Purification procedures did not alter histamine release responses to anti-IgE or the calcium ionophore A23187, and treatment of UMC with an anti-CD32 monoclonal antibody (IV.3) did not induce histamine release or alter anti-IgE-induced release. These data suggest that UMC may possess unique phenotypic characteristics, and support the concept of mast cell heterogeneity.