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K Sheibani

Publications and source records attributed to K Sheibani.

At least 91 records · Page 5Linked to original sources
PubMed1986

L&H variants of Reed-Sternberg cells express sialylated Leu M1 antigen.

Anti-Leu M1 generally does not stain the lymphocytic and histiocytic (L&H) variants of Reed-Sternberg cells in the lymphocyte predominant type of Hodgkin's disease. However, the authors found that after neuraminidase treatment for removal of sialic acid, the L&H cells in more than half of the cases studied could be stained by anti-Leu M1. This result strongly suggests that L&H cells differ from the Reed-Sternberg cells in other types of Hodgkin's disease in their unique capacity to sialylate the 150-kd Leu M1 antigen.

Antigens↗
PubMed1986

Preoperative imaging of colorectal carcinoma with 111In-labeled anticarcinoembryonic antigen monoclonal antibody.

Patients with primary, recurrent, or metastatic colorectal adenocarcinoma were given injections of 200 micrograms of anticarcinoembryonic antigen (CEA) monoclonal antibody labeled with 2 mCi of 111In (Indacea). Patients were imaged at 24 and 48 h. Celiotomy was performed on 40 patients between 3 and 17 days post-Indacea injection. Of 16 primary tumors, 11 (69%) were imaged. Of six extrahepatic recurrences, none was imaged. Intrahepatic metastases were visualized as negative images in 10 of 24 (42%) patients. On the basis of the activity in tissue expressed as a percentage of the total radioactive dose per kg injected into the patient (% ID/kg), extrahepatic tumors that were imaged using Indacea had a significant uptake of radiolabel in the tumor [5.99 +/- 0.91% ID/kg (SE)] and in the associated normal mesenteric lymph nodes (12.0 +/- 2.4% ID/kg). The CEA content of these tumors was high (13.3 +/- 4.7 micrograms/g), and, histologically, the CEA was located primarily apically or intraluminally. Intrahepatic tumor imaging correlated only with tumor size. The greatest Indacea uptake was seen in normal liver (22.1 +/- 3.2% ID/kg). Low Indacea uptake was seen in fat (0.21 +/- 0.05% ID/kg) and bowel wall (1.11 +/- 0.17% ID/kg). In conclusion, Indacea imaging of colorectal carcinoma is specific for high concentrations of accessible CEA in CEA-bearing tumors or in lymph nodes draining these tumors. The successful clinical use of monoclonal antibodies for tumor imaging and therapy will require careful selection of patients for a number of antigen-related parameters including antigen content and distribution in tumors. This information will only come from careful correlation between image results and tissue analysis. High uptake by normal liver tissue is the major unresolved problem with labeled antibody imaging.

Antibodies, Monoclonal↗
PubMed1986

Testis imaging with 111In-labeled anticarcinoembryonic antigen monoclonal antibody: identification of carcinoembryonic antigen in normal germ cells.

A monoclonal antibody to carcinoembryonic antigen (CEA) labeled with 111In (Indacea) was used to image tumors in patients with colorectal cancer. The anti-CEA antibody has a high affinity (2.6 X 10(10) M-1) for CEA and does not cross-react with normal cross-reacting antigen, biliary glycoprotein-1, or tumor-extracted, CEA-related antigen. During the course of these studies, it was noted that a significant number of male patients (20 of 27, 74%) showed uptake of Indacea in the testes. In order to determine if the Indacea uptake was specific, 20 testicular specimens were analyzed by immunohistological methods using five different anti-CEA CEA monoclonal antibodies recognizing five different epitopes on CEA. In 18 cases (90%) germ cells were uniformly stained by all five antibodies. Fresh frozen testis tissue was homogenized in water and precipitated with 1.0 M perchloric acid. The supernatant contained a CEA-like material as measured by an enzyme immunoassay specific for CEA. The same supernatant was radiolabeled with 125I and immunoprecipitated with anti-CEA monoclonal antibodies. Sodium dodecyl sulfate:polyacrylamide gel electrophoresis of the immunoprecipitates revealed a single species (Mr 180,000) which was indistinguishable from CEA. This study documents the first description of CEA in the germ cells of normal testis. The CEA in the testis was accessible to circulating monoclonal antibodies in the majority of male patients tested.

Adult↗
PubMed1985

Neoplastic B cells with cerebriform nuclei in follicular lymphomas.

Three cases of follicular lymphoma in which the follicular center cells exhibited pronounced nuclear irregularities, i.e., convoluted and cerebriform shapes, are described. The cytoplasm in B5-fixed sections was scanty to abundant and showed pale to clear staining, with interlocking cell borders. Although the architectural pattern in these cases suggested B-cell lymphoma, the cytologic features suggested a T-cell phenotype. Immunologic studies of frozen sections by immunohistochemical techniques in all three cases, as well as cell suspension studies in two cases, showed that the follicular center cells, including those with convoluted and cerebriform nuclei, were clearly monoclonal B cells, as evidenced by the presence of only one immunoglobulin light chain on the surfaces. The results of this study suggest that the follicular architectural pattern is a more reliable predictor of the immunologic phenotype than are the cytologic features.

Aged↗
PubMed1985

Monocytoid B lymphocytes: their relation to the patterns of the acquired immunodeficiency syndrome (AIDS) and AIDS-related lymphadenopathy.

It was shown recently that monocytoid cells express B-cell-restricted antigens and polyclonal surface immunoglobulins, and the term monocytoid B lymphocytes (MBL) has thus been offered as a more appropriate designation. Although most commonly seen in toxoplasmic lymphadenitis, MBL have been observed in a variety of reactive and neoplastic conditions involving lymph nodes. In the present study MBL were found in 17 of 22 lymph nodes from 20 patients with the acquired immunodeficiency syndrome (AIDS) and AIDS-related lymphadenopathy. In all 17 samples, the MBL were found in lymph nodes with florid reactive follicular hyperplasia, and they were geographically close to the hyperplastic lymphoid follicles. However, MBL were not detected in lymph nodes showing involuted follicles or lymphocyte depletion. The disappearance of MBL apparently parallels the progressive involution of secondary follicles. Leu-3+/Leu-2+ (T-helper/T-suppressor) ratios were studied in 14 lymph node cell suspension samples and ten peripheral blood samples. The lymph node Leu-3+/Leu-2+ ratios were significantly lower in AIDS-related lymphadenopathy than in non-AIDS-related reactive follicular hyperplasia (P less than 0.001); the peripheral blood ratios were decreased in nine of the ten cases. The diminished T-helper status in patients with AIDS and AIDS-related lymphadenopathy may be relevant to the immunopathogenesis of follicular involution and, indirectly, to the disappearance of MBL.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Small lymphocytic lymphoma. Morphologic and immunologic progression.

The large cell lymphoma (LCL) that occurs in patients with chronic lymphocytic leukemia (Richter's syndrome) has generally been shown to be of the same light chain type as the original chronic lymphocytic leukemia (CLL). The authors now report on a patient with diffuse well-differentiated lymphocytic lymphoma (WDL) of the kappa light chain type who in the course of his illness first had the blood picture of CLL and then developed malignant lymphoma of large cell ("histiocytic") type, which expressed lambda light chains. Despite an extensive multiparameter investigation, we could not determine with certainty whether the presence of two morphologically and immunologically different lymphomas represented proliferation of two distinctly separate clones or whether it represented clonal evolution of the disease with an alteration in immunoglobulin light chain associated genes. The results of the study, however, suggest that the development of lymphoma with expression of a different immunoglobulin light chain may not necessarily indicate the occurrence of a second primary. This study also illustrates the necessity for sequential lymph node biopsies to document progression of disease in patients with low-grade lymphoproliferative disorders and indicates that the immunologic phenotype of a B-cell neoplasm in a given patient should not be assumed to remain constant.

Antigens, Surface↗
PubMed1985

Peripheral T cell lymphoma: immunologic and cell-kinetic observations associated with morphological progression.

Peripheral T cell lymphomas (PTCLs) form a morphologically heterogeneous group of non-Hodgkin's lymphomas that are generally considered to have immunophenotypes associated with mature T cells, usually those of helper T cells. We now describe and correlate the clinical, morphological, immunologic, and cell-kinetic findings based on the evaluation of eight tissue samples obtained at various times from a 13-year-old girl with PTCL. The early morphological expressions of this patient's PTCL were those of diffuse mixed-cell lymphoma and focal large-cell lymphoma (LCL) evolving from the histologic picture of an atypical immune response (AIR). These morphological findings were associated with an immature T cell immunophenotype associated with cortical thymocytes--namely, sheep erythrocyte rosette (sER)+, T11+, Leu-2a+, Leu-3a+, HLA-DR+, OKT6-, OKT9+, OKT10+--and with cell-kinetic findings that showed no evidence of aneuploidy and few cells in S phase. Diffuse pleomorphic LCL developed, which was associated with further dedifferentiation of the neoplastic T cells to the immunophenotype sER-, T11+, Leu-2a-, Leu-3a-, HLA-DR+, OKT6-, OKT9+, OKT10- and with cell-kinetic findings that demonstrated a distinct aneuploid population and a dramatic increase in the percentage of cells in the S phase. The immunophenotype of the PTCL at the time of the patient's death was T11-, Leu-2a-, Leu-3a-, HLA-DR+, OKT6-, OKT9+, OKT10-, an immunophenotype indistinguishable from that of a non-B non-T cell lymphoma. The immunologic findings in this case also suggest that an AIR in some cases may represent a prelymphomatous state or may be a morphological expression of PTCL. These observations indicate that PTCLs may be characterized by rapidly changing clinical, morphological, immunologic, and cell kinetic findings which are best evaluated by multidisciplinary studies.

Adolescent↗
PubMed1984

Antikeratin antibodies in tumor diagnosis. Distinction between seminoma and embryonal carcinoma.

The authors investigated the presence and distribution of keratin in germ cell tumors using a rabbit-anti-keratin antiserum and a monoclonal antikeratin antibody--which is specific for keratin classes of 40, 50, and 56.5 kdaltons--by various immunohistochemical methods on frozen sections, alcohol-fixed, and formalin-fixed paraffin-embedded tissues. Thirty-four germ cell tumors were studied. These were the following: 18 seminomas, 10 embryonal carcinomas, 2 teratocarcinomas, 3 yolk sac tumors and 1 choriocarcinoma. All seminomas, including four poorly differentiated (so-called anaplastic seminomas), gave negative results, regardless of the method employed. Embryonal carcinoma, the epithelial component of the teratocarcinoma, the yolk sac tumors, and choriocarcinoma were at least focally positive for keratin. The monoclonal antibody provided a cleaner background and stronger staining than the rabbit-anti-total-human-epidermal-keratin antibody. Best results were obtained from fresh-frozen sections or alcohol-fixed, paraffin-embedded materials. Formalin-fixed, nonseminomatous tumors, when predigested with trypsin and incubated overnight with primary antibody, gave no false-negative results but staining was often focal. The authors' results agree with the reported absence of detectable keratin in primordial germ cells of the normal testis, and with prevailing concepts of the histogenesis of germ cell tumors. These results indicate that the presence or absence of keratin by immunocytochemical methods can be helpful in distinguishing seminoma from embryonal carcinoma.

Antibodies, Monoclonal↗
PubMed1984

"Monocytoid" cells in reactive follicular hyperplasia with and without multifocal histiocytic reactions: an immunohistochemical study of 21 cases including suspected cases of toxoplasmic lymphadenitis.

The presence of "monocytoid" cells in toxoplasmic lymphadenitis is a distinctive histopathologic finding, but the exact nature and immunologic properties of these cells have not been characterized clearly. The authors have evaluated the immunohistochemical features of monocytoid cells in fresh-frozen and paraffin-embedded, fixed lymph node material from 21 cases of reactive follicular hyperplasia including suspected cases of toxoplasmic lymphadenitis. This study revealed that monocytoid cells contain (1) the B lymphocyte surface membrane differentiation antigens B-1 and BA-1, and (2) surface membrane-associated immunoglobulin light chains in a polyclonal distribution. No positive reaction was observed when monocytoid cells were studied with monoclonal antibodies specific for peripheral T cells or with antibodies considered to be specific for cells of the monocytic/histiocytic cell line. The results indicate that monocytoid cells, despite their distinct morphologic appearance, have surface marker characteristics of polyclonal B lymphocytes. Therefore, "monocytoid B lymphocytes" would be a more appropriate designation for these cells.

Histiocytes↗
PubMed1984

Enzyme immunohistochemistry: technical aspects.

The enzyme immunohistochemical techniques developed during the past decade have contributed greatly to our understanding of disease processes and have become an essential tool in the evaluation of many disease states. The availability of these techniques permits the visual localization of tissue antigens in permanent preparation with the potential for visualization of adjacent tissue morphology. This paper outlines the theoretical principles underlying immunohistochemical techniques, the new technical developments and pitfalls of currently available techniques, characterization of nonhazardous chromogens, and quality control for these procedures.

Chromogenic Compounds↗
PubMed1984

Immunohistology of lymphoproliferative disorders.

Malignant lymphomas have come to be recognized as neoplasms of the immune system. These lymphoproliferative disorders demonstrate surface and cytoplasmic antigenic phenotypes that reflect qualitative and quantitative alterations or aberrant expression of genetic material. Traditionally, cell suspension studies have been used for phenotypic analysis. Alternative immunohistologic methods can be used to profile immunophenotypes in situ. Most lymphoproliferative disorders can be readily classified as T or B cell malignancies, and criteria have been evolved to differentiate neoplastic from reactive/physiologic expansions of lymphoid clones. However, antigenic phenotypic expression does not always correspond to known immunophenotypes of subsets of T or B cells and probably reflects the complexity of neoplastic transformation. Currently, frozen tissue sections, preferably in combination with cell suspension analysis using cytocentrifuge preparations and/or flow cytometry, can provide information to phenotype lymphomas classified by the International Formulation or other nomenclature. Their continued utility depends on development of and adherence to strict quality assurance programs.

B-Lymphocytes↗
PubMed1983

The demonstration of terminal deoxynucleotidyl transferase on frozen tissue sections and smears by the avidin-biotin complex (ABC) method.

A method using avidin-biotin complex (ABC) to detect the presence of the enzyme terminal deoxynucleotidyl transferase (TdT) is described and compared with a proven indirect immunofluorescence method. The material studied consisted of: (1) peripheral blood and bone marrow smears from 17 patients with leukemia (ALL, 8; CLL, 3; AML, 6), six normal controls, one T-ALL cell line, and (2) frozen tissue sections from four patients with lymphoblastic lymphoma (LL), two patients with nodular poorly differentiated lymphocytic lymphoma (NLPD), two patients with reactive follicular hyperplasia (RFH) and one calf thymus. The slides from patients with ALL had from 30 to 90% cells with nuclear positively by the ABC technique. Slides from patients with CLL were negative, as were the normal peripheral blood smears. Normal bone marrow smears contained less than 5% positive cells. The T-ALL cell line was 100% positive. The frozen tissue sections from the patients with LL and the calf thymus contained numerous positive cells, while all of the sections from the patients with NLPD and RFH were negative. A good correlation existed between the ABC and the indirect immunofluorescence methods. The ABC method described is both more specific and more sensitive than the previously described techniques in detecting TdT in tissue sections and smear preparations.

Antigens, Surface↗
PubMed1983

Characterization of blood mononuclear and cultured cells in hairy cell leukemia.

The nature of neoplastic cells in hairy cell leukemia (HCL) is still controversial. Most reports favor derivation from B cells, but some have suggested origin from monocytes/histiocytes, T cells, or even a hybrid Ig-bearing lymphocyte with phagocytic activity. We established a new cell line from peripheral blood of a patient with typical HCL. The morphologic, immunocytochemical, and functional properties of the new cell line were identical with the patient's original HC. Both cell types demonstrated the irregular, fine cytoplasmic projections characteristic of HC, were weakly phagocytic, markedly positive for tartrate-resistant acid phosphatase, and had variable nonspecific esterase reactivity. Low percentages of EAC-rosetting cells were found (8% original specimen and 6% cultured cells) and a minute amount of IgG, IgA, and IgM were synthesized by the new cell line. A small proportion of cells (13% original specimen and 12% cultured cells) bore SIg when stained with F(ab)2-fragment polyvalent antiserum. Our observations indicated that HC were a slowly proliferating cell population with immunochemical and functional characteristics of both B and monocyte/histiocytic cells.

Aged↗
PubMed1983

Coincidence of B-cell chronic lymphocytic leukemia and cutaneous T-cell lymphoma (mycosis fungoides): immunologic characterization by monoclonal antibodies.

Although rare cases of chronic lymphocytic leukemia (CLL) of the T-cell type have been reported, CLL is more commonly found to be a neoplastic lymphoproliferative disease of B-cell origin. In this article, we describe a patient with long-standing CLL that was immunologically shown to be of the B-cell type, who, during the course of his disease, developed cutaneous T-cell lymphoma (CTCL), which was shown to be of the helper/inducer subtype. The neoplastic lymphoid cells in the skin infiltrate differed morphologically and immunologically from those in the peripheral blood. The occurrence of CTCL during this patient's clinical course represents a second neoplasm arising from a different cell line, rather than a tissue manifestation of the patient's CLL. To our knowledge, this is the first report in which the occurrence of CTCL is documented in a patient with immunologically known B-cell CLL. In addition to establishing the presence of B-cell CLL and CTCL of the helper/inducer T-cell type in the same patient, this case report demonstrates the usefulness and necessity of evaluating lymphoproliferative disorders by means of a multidisciplinary approach.

Aged↗
PubMed1981

Comparison of alternative chromogens for renal immunohistochemistry.

Renal immunomicroscopy using enzyme labeled reagents has been shown to be a reliable method for the identification of immunoglobulins and complement in the routine evaluation of glomerular disease. However, the potential carcinogenicity of benzidine derivatives used in the procedure represents a major disadvantage of the technique. With a series of 55 renal biopsy specimens evaluated by light microscopy, immunofluorescence, and electron microscopy from patients with a variety of renal diseases, a study was done comparing aminoethylcarbazole and the Hanker-Yates reagent (p-phenylenediamine and pyrocatechol), chromogens chemically unrelated to benzidine. Aminoethylcarbazole was not suitable for renal immunomicroscopy, since in cases of antiglomerular basement membrane disease the color reaction product was finely granular at high magnification. Specimens immunostained with the Hanker-Yates reagent yielded permanent water insoluble reaction products and immunomicroscopic patterns identical to the results observed with immunofluorescence in all cases. To our knowledge, no carcinogenic properties have been identified for p-phenylenediamine or pyrocatechol. The Hanker-Yates reagent may be used routinely for renal enzyme immunomicroscopic studies with no currently identified carcinogenic hazard to laboratory personnel.

3,3'-Diaminobenzidine↗
PubMed1981

Immunohistochemistry of fresh-frozen lymphoid tissue with the direct immunoperoxidase technic.

Recent evidence suggests that immunofluorescence is superior to immunohistochemistry for the study of lymphomas, since the latter procedure often results in identification of polyclonal cytoplasmic immunoglobulins or negative immunostaining in non-Hodgkin's lymphomas marking monoclonal with immunofluorescence. However, immunohistochemical studies are usually applied to paraffin-embedded tissues. A modified direct immunoperoxidase procedure using fresh-frozen cryostat tissue sections, short incubation with peroxidase-labeled antikappa and antilambda antisera, and chromogens chemically unrelated to benzidine was developed. Non-Hodgkin's lymphomas previously characterized by direct immunofluorescence showed monoclonal surface membrane-associated light chains outlining each neoplastic cell. Follicular (nodular) lymphomas were characterized by monoclonal light chains in neoplastic nodules with compressed negative or polyclonal rims. Diffuse non-Hodgkin's lymphomas demonstrated diffuse individual cellular monoclonal staining. Five normal lymph nodes showed polyclonal immunostaining of follicular centers. The immunostained slides resulting from this procedure are permanent preparations amenable to counterstaining.

Frozen Sections↗