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Biomedical subjects

P Biberfeld

Publications and source records attributed to P Biberfeld.

At least 109 records · Page 6Linked to original sources

CEA in colonic adenocarcinomas and precancerous lesions. An immunohistochemical study with a novel monoclonal antibody.

Using a new anti-CEA (CB-CEA-1) murine monoclonal antibody, the expression of carcinoembryonic antigen (CEA) was studied in normal, premalignant and malignant human adult tissues with particular emphasis on colorectal mucosa. The CB-CEA-1 epitope was poorly expressed in normal adult tissues but was consistently found in colon cancers and adenomas in distinctive immunohistochemical patterns. Some apical staining was found with CB-CEA-1 in cells of normal colon mucosa whereas colon adenocarcinomas had a predominantly cytoplasmic staining pattern. Colonic adenomas presented a varied staining pattern. Some showed apical staining, others a CEA distribution pattern similar to that of adenocarcinomas, particularly those with a villous component. Our findings indicate a differential expression of CB-CEA-1 in adenoma cells in relation to their potential for malignant transformation. The possible usefulness of this Mab defined epitope for diagnostic and therapeutic purposes is indicated.

Adenocarcinoma↗

Lymphadenopathy in HIV infection: histological classification and staging.

The histological alterations seen in HIV-related lymphadenopathy have been described with different terms by different authors. In order to facilitate comparisons of results from various laboratories, a group of pathologists of the European Lymphoma Study Group (later the European Association for Haematopathology) have proposed a histological classification for the evaluation of HIV related lymphadenopathy. Most observers agree that the morphological and immunohistochemical alterations in the follicles (germinal centres) are the most conspicuous and earliest changes seen. The follicular alterations were therefore used as the basis for the proposed classification. In addition, some features occasionally seen were also included, i.e. angioimmunoblastic hyperplasia, multicentric Castleman-like lesions, and vascular lesions, especially pretumorous and tumorous stages of Kaposi's sarcoma. The proposed classification was used by the members of the group of a collection of lymph nodes compiled from the various centres. The classification was shown to be reproducible and to have clinical relevance in staging of the patients. The prognostic relevance as to the survival of the patients has to be further substantiated by follow-up studies. The proposed classification offers a common terminology for the alterations previously described by different terms by various authors.

AIDS-Related Complex↗

Utilization of human hematopoietic cell lines for the propagation and characterization of HBLV (human herpesvirus 6).

In 1986, we reported the discovery and isolation of a novel human herpesvirus (HBLV) from AIDS and other lymphoproliferative disorders. Because HBLV is distinct from other members of the herpesvirus family and can infect B- and T-lymphocytes and other human cells (megakaryocytes and glioblastoma cells), we suggested human herpesvirus-6 (HHV-6) as the taxonomic designation for this virus. In cultures from patients' peripheral blood, the evidence of HBLV can be recognized from the appearance of short-lived giant cells (2-10%), which are large, refractile, and are often mono- and binucleated. As these cells degenerate, extracellular virus particles are found in the culture medium. HBLV can infect fresh mononuclear cells, established B- and T-lymphoblastoid cell lines, megakaryocytes and glioblastoma cell lines. HBLV infection can be detected by: a. morphological changes; b. indirect immunofluorescence assay, in situ hybridization, southern blot analysis, polymerase chain reaction amplification; and c. electron microscopy. Because of its wide cell tropism, HBLV DNA sequences have been detected in B-cell lymphomas and short term cultured cells from Sjogren's patients. Expression of HBLV RNA was also detected in sarcoidosis. The etiological role of HBLV in human tumors is unclear. While in vitro data may not necessarily apply to in vivo conditions, the infection of various cell lines from tumors and fresh mononuclear cells suggests HBLV involvement in a variety of diseases.

Cell Line↗

HIV encephalopathy and lymphadenopathy: cells associated with viral antigens.

HIV associated subacute, micronodular encephalitis and lymphadenopathy were compared with regard to demonstrable HIV antigens and characterization of HIV antigen expressing cells. In the brain, both gag- and env-coded antigens were confined to cells of micronodular lesions with immunophenotype of monocyte/macrophages (KiM6+, 9.4+, CD4+/-). The micronodular lesions were also infiltrated by some lymphoid cells, predominantly CD8+. In lymphadenopathic nodes, gag-encoded antigens were demonstrable almost exclusively in follicles/germinal centres in association with follicular dendritic cells, whereas env-antigens usually were not found. Follicular involution was related to destruction of follicular dendritic cells and infiltration of CD8+ lymphocytes within the germinal centres. During follicular involution, HIV-gag antigens diminished in parallel with destruction of the network of dendritic reticulum cells. These findings indicate important tissue related differences in HIV expression. In addition, a possible participation of CD8+ cells in the pathogenesis of HIV induced tissue lesions is suggested.

AIDS-Related Complex↗

Utilization of human hematopoietic cell lines for the propagation and characterization of HBLV (human herpesvirus 6).

Details of the productive infection of established human cell lines of diverse origin by HBLV (also designated Human Herpesvirus 6) are described in this report. The infection and replication of HBLV in several T and B lymphoid and other cell lines was observed by electron microscopic examination, by the detection of viral antigen expression by indirect immunofluorescence assay (IFA) and by the presence of HBLV DNA by Southern blot hybridization. Several of these cell lines produced large amounts of virus. For this reason and because of the absence of other human herpesviruses, these lines have provided a valuable resource for the preparation of reagents and the development of assays for the detection and characterization of HBLV. The isolation and characterization of new HBLV isolates from patients with chronic fatigue syndrome were also facilitated by using some of the cell lines reported here. The host range of HBLV in established cell lines, therefore, does not appear to be limited to the B lymphocytes, as initially suggested by in vivo studies. The infection of T and B lymphocytes, megakaryocytes and neuronal cells in vitro suggests a need for the evaluation of diverse hematological and neurological disorders to shed light on a possible HBLV involvement.

Blotting, Southern↗

Angiogenic properties of Kaposi's sarcoma-derived cells after long-term culture in vitro.

Cells derived from lung biopsies and pleural effusions from AIDS patients with Kaposi's sarcoma (KS) of the lungs were established in long-term culture with the aid of conditioned medium from HTLV-II-transformed T cells (HTLV-II CM). These AIDS-KS cells were similar to the so-called spindle cells in KS lesions and had some of their features. They produced factors that supported their own growth (autocrine) and the growth of other cells (paracrine), including umbilical vein endothelium and fibroblasts. That the AIDS-KS cells also expressed potent angiogenic activity was demonstrated by the chorioallantoic membrane assay and by subcutaneous inoculation of AIDS-KS cells into nude mice, which resulted in the development of angiogenic lesions composed of mouse cells and showing histological features similar to those of human KS lesions. These data suggest that AIDS-associated KS and possibly other types of KS may be initiated by signals that induce the growth of particular cells (spindle cells of lymphatic or vascular origin) and the expression of autocrine and paracrine activities.

Acquired Immunodeficiency Syndrome↗

Kaposi's sarcoma cells: long-term culture with growth factor from retrovirus-infected CD4+ T cells.

Studies of the biology and pathogenesis of Kaposi's sarcoma (KS) have been hampered by the inability to maintain long-term cultures of KS cells in vitro. In this study AIDS-KS-derived cells with characteristic spindle-like morphology were cultured with a growth factor (or factors) released by CD4+ T lymphocytes infected with human T-lymphotropic virus type I or II (HTLV-I or HTLV-II) or with human immunodeficiency virus type 1 or 2 (HIV-1 or HIV-2). Medium conditioned by HTLV-II-infected, transformed lines of T cells (HTLV-II CM) contained large amounts of this growth activity and also supported the temporary growth of normal vascular endothelial cells, but not fibroblasts. Interleukin-1 and tumor necrosis factor-alpha stimulated the growth of the KS-derived cells, but the growth was only transient and these could be distinguished from that in HTLV-II CM. Other known endothelial cell growth promoting factors, such as acidic and basic fibroblast growth factors and epidermal growth factor, did not support the long-term growth of the AIDS-KS cells. The factor released by CD4+ T cells infected with human retroviruses should prove useful in studies of the pathogenesis of KS.

Acquired Immunodeficiency Syndrome↗

Immunohistochemical monitoring of metastatic colorectal carcinoma in patients treated with monoclonal antibodies (MAb 17-1A).

A therapeutic trial using repeated doses of a mouse monoclonal antibody against the tumor-associated antigen (TAA) CO17-1A in metastatic colorectal carcinomas was carried out. Metastatic lesions sampled by repeated thick needle (1.2 mm) biopsies during therapy were examined immunohistochemically for the presence of various TAAs, mouse IgG, complement, and infiltrating leukocytes. The CO17-1A was consistently expressed in all cases along the basement membrane of tumor glands and could only be demonstrated on cryostat sections whereas the TAAs GICA19-9, GA73-3, and Br55-2 were also visualized in B5-fixed paraffin-embedded biopsies. The CO17-1A and GA73-3 were predominantly present at the basal region in contrast to the GICA 19-9 and Br55-2 which were predominant at the luminal and the apical region of the tumor glands. Antigenic modulation was not seen either after 24-72 h or during prolonged treatment. In all cases the infused mouse IgG was detected, from 24 h after infusion up to 6-8 weeks, mainly along the basal region of tumor glands. In 13/14 posttreatment biopsies, complement factor C3 was found at the same sites as mouse IgG. In 6 out of 9 posttreatment biopsies an increase in mononuclear cells (monocytes, natural killer (NK) cells and/or T cells) was observed. Monocytes were close to the tumor cells whereas NK cells and T cells were predominantly scattered in the stroma.

Adult↗

Prognostic significance of immunoglobulin isotype expression in B-cell non-Hodgkin's lymphoma.

Lymph node biopsies from 170 patients with untreated non-Hodgkin's lymphomas (NHL) of B-cell type were immunophenotyped and analyzed for the Ig heavy and light chain isotypes and their relation to prognosis. IgM alone was more frequently seen in high grade (53%) compared to low grade (20%) NHL. In contrast, IgM/IgD isotypes were more frequent in low grade (47%) than in high grade NHL (20%). IgG or IgA heavy chain, alone or in combination with other heavy chain isotypes, were expressed with the same frequencies in both low (32%) and high (27%) grade NHL. Clonally restricted kappa light chain expression was noted in 64% of low grade and 66% of high grade NHL patients. Only in chronic lymphocytic leukemia (CLL) and immunocytoma (IC) was a shorter survival time noted for patients with tumors expressing IgG and/or IgA heavy chains compared to those expressing IgM or IgM/IgD (P less than 0.001). This difference was not seen as being low grade follicle center cell-derived (FCC) or high grade NHL. The expression of kappa light chains on the tumor cells was associated with a significantly longer survival in CLL and IC patients only (P less than 0.01).

Adult↗

Human herpesvirus-6 (HHV-6, HBLV) in sarcoidosis and lymphoproliferative disorders.

Serologic studies were done to estimate the antibody prevalence against human herpesvirus 6 (HHV-6) in patients with malignant lymphomas, Sjögren's syndrome and sarcoidosis. Serologic studies showed IgG antibody titers against HHV-6 in up to 41% of patients with sarcoidosis, 50-70% with malignant lymphomas and in 36% with Sjögren's syndrome. In situ hybridization on lymph node biopsies was positive for HHV-6 genome in 1 out of 5 sarcoidosis lymph nodes.

Antibodies, Viral↗

IgG antibodies to human herpesvirus-6 in children and adults and in primary Epstein-Barr virus infections and cytomegalovirus infections [corrected].

Antibody titers against human herpesvirus-6 (HHV-6) were determined in 80 healthy adults and 100 children and teenagers from Sweden to gain information on the role of the virus and its epidemiology. Based on a positive immunofluorescence titer of 1:10 and above, about 85% of the adults and children were seropositive with 60% seropositivity of children below age one year. Titers were generally higher in patients with simultaneous EBV or CMV infection, yet crossreactivity appeared essentially no problem. HHV-6 thus is ubiquitous like other herpesviruses. Primary infection seems to occur early in life, and reactivation or delayed primary infection may be associated with a variety of disorders.

Adolescent↗

Clinical effects of monoclonal antibodies (MAb 17-1A) in patients with metastatic colorectal carcinomas.

Ten patients with metastatic colorectal carcinoma were treated with MAb 17-1A (IgG2A). Before infusion, MAb was incubated in vitro with isolated autologous blood mononuclear cells. Treatment was given in repeated courses (2-4 times) to a maximum dose of 1000 mg of MAb 17-1A. One patient achieved a clinical complete remission, two patients had a minor response and one patient had stable disease for 5 months. The median survival for the four responders was 19 months compared to 7 months for the six non-responders. Therapy was well tolerated. In this series, 32 infusions of MAb 17-1A were given. The serum half-life of MAb 17-1A was approximately 22 hours. All patients developed anti-mouse antibodies of both IgG and IgM classes. No relation between adverse reactions and anti-mouse antibodies was seen. At 3 occasions allergic reactions were noted. Skin test with MAb 17-1A seems to reliably predict for allergic reactions.

Adult↗

Buoyant density characterization of neoplastic cell populations in patients with chronic B-lymphocytic leukemia.

Leukemic cells from a series of patients with chronic B-lymphocytic leukemia (CLL) were analyzed for their buoyant density on discontinuous Percoll gradients. The density profile varied markedly between different patients and also between samples from different body compartments within the same patient. A good correlation was observed between buoyant density and maturation stage of the leukemic clones as judged by Ig-expression and their reactivity with a panel of monoclonal antibodies. Phorbol-ester-induced changes in the leukemic cells were found to be accompanied by a general decrease in their buoyant density. No correlation between density and clinical parameters such as cell counts, clinical stage and survival could be noted. Buoyant density characterization of leukemic B-cell populations is seen as a useful, rapid and simple marker of compartmentalization within the B-lymphocyte maturation spectrum but its clinical relevance remains to be established.

Antigens, Surface↗

B-cell compartment in the thymus of patients with myasthenia gravis and control subjects.

An increased number of CD19, 20, and 22 positive B cells, compared to the number of Ig-positive cells, is regularly found in the thymic medulla of normal thymus, suggesting that a B-cell population normally resides in thymic medulla that lacks Ig expression. However, some of the CD20-positive cells seem to co-express keratin and MR19, suggesting an epithelial origin. The medullary B cells found in normal thymus could be precursors of the tumor cells in "mediastinal clear cell lymphomas of B-cell type." In follicular hyperplasia in MG, the medullary epithelial network is deformed and partly destroyed, and the interlobular/perivascular spaces are expanded. Follicles with follicular dendritic cells are found in both interlobular/perivascular spaces and "punched out" lesions in the medullary epithelium. The B cells are greatly increased in MG thymuses compared with control thymuses. These cells are found mainly in the follicles, but they are also dispersed in the medulla and the interlobular/perivascular spaces. The immunophenotype and distribution of B and T cells as well as the follicular dendritic cells in the hyperplastic follicles are similar to those of reactive follicles in lymph nodes. Our findings are consistent with the contention that in MG there is an autoimmune activation of B cells that normally reside in the thymic medulla. This activation leads initially to follicular hyperplasia in the medullary epithelium with destruction of medullary epithelial cells. The prolonged immune reaction in the autoimmune process induces a fibronectin-rich stroma formation and increased vascularization. The result is a remodeling of the thymic architecture with expansion of the perivascular/interlobular spaces replacing the destroyed medulla.

Antigens, Differentiation↗

Lymphadenopathy in HIV (HTLV-III/LAV) infected subjects: the role of virus and follicular dendritic cells.

Studies of human immunodeficiency virus (HIV) associated lymphadenopathy by histopathology and immunopathology showed conspicuous changes of follicular B-cell areas from a marked hyperplasia to complete involution. Immunohistochemistry showed a corresponding increase in follicular dendritic reticulum cells (FDRC) followed by progressive destruction of these cells during involution, concomitant with invasion of follicles by T-cells. HIV gag antigens were predominantly associated with FDRC in hyperplastic follicles and diminished during involution. Virus replication was by in situ hybridization seen predominantly in follicles, presumably reflecting productive infection of CD4+ cells and/or FDRC. It is concluded that local effects of the virus play an important role in HIV lymphadenopathy. The marked cytopathogenic effects on FDRC indicate that HIV infection with lymphadenopathy represents not only a disease of CD4+ cells but also of follicular antigen presenting cells (FDRC).

AIDS-Related Complex↗