Search PubMed⌕ Search

Biomedical subjects

G Pallesen

Publications and source records attributed to G Pallesen.

At least 73 records · Page 4Linked to original sources
PubMed1989

Specific depletion of mature T lymphocytes from human bone marrow.

An effective method for specific depletion of mature T lymphocytes from human bone marrow mononuclear cells (BMMC) with preservation of prethymic T cells and natural killer (NK) cells is presented. The BMMC were incubated with F101.01, a monoclonal antibody recognizing an epitope of the T-cell receptor-CD3 complex, and subsequently with immunomagnetic beads. Flow cytometric analysis demonstrated that mature T cells were efficiently depleted and that NK cells and prethymic T cells were preserved in the BMMC. Furthermore, T cell-mediated immune reaction as measured by thymidine incorporation after stimulation with phytohaemagglutinin was abolished, whereas NK activity as measured by 51Cr release using K562 as target cells was preserved. Recovery of colony-forming units of granulocyte-macrophages was 60-70%.

Bone Marrow↗
PubMed1989

B cell associated monoclonal antibody L26 may occasionally label T cell lymphomas.

Monoclonal antibody L26 has been shown to be a very sensitive marker for B lymphocytes in formalin-fixed, paraffin-embedded tissue. Most studies have found that the antibody is also highly specific for B cells, although a few examples of L26-positive T cell lymphoma (TCL) have been reported. We have studied L26 reactivity in 50 TCLs (all previously extensively immunophenotyped on frozen sections) and found positive labelling in 4 cases (3 pleomorphic, medium and large cell type with surface membrane staining; 1 T-anaplastic large cell type with cytoplasmic staining). The finding that L26 may give surface labelling in occasional TCLs (particularly of the pleomorphic, medium and large cell type) indistinguishable from that seen in B cell lymphomas emphasises the importance of always using diagnostic MAbs in combination if the risk of misinterpretation of lymphoma cell lineage is to be minimised.

Antibodies, Monoclonal↗
PubMed1989

Follicular involution in HIV lymphadenopathy. A morphometric study.

Lymph node biopsies from 75 HIV infected patients (71 homo- and bisexual men, 3 hemophiliacs and 1 woman) were studied using immunohistochemical methods with monoclonal antibodies (Mabs) against B lymphocytes, subsets of T lymphocytes, follicular dendritic cells (FDC) and HIV gag proteins p24 and p18. Histopathological changes were classified as follicular hyperplasia (FH), fragmentation (FF), atrophy (FA) and depletion (FD). Immunohistochemical stainings were quantified with the help of an Image Quantifier (IQ) and the reactivity for respective Mab-defined antigen was related quantitatively to other antigens and histopathological changes. Such measurements showed an increase in FDC in biopsies with FH and FF histology and a decrease in FA and FD cases in comparison with cases with non-HIV related lymphadenopathy. In addition it was found that the decrease in FDC was correlated with an increase in CD8+ within the follicles. Double immunostainings for p24 and various cellular markers showed that p24 was predominantly associated with follicular dendritic cells. Essentially the same findings were observed in the lymph nodes irrespective of risk group. Possible mechanisms involved in follicular involution in HIV-related lymphadenopathy are discussed.

AIDS-Related Complex↗
PubMed1989

Detection of T cells in paraffin wax embedded tissue using antibodies against a peptide sequence from the CD3 antigen.

Rabbit polyclonal antibodies were raised against a proline rich, peptide sequence, comprising 13 amino acids, in the cytoplasmic domain of the CD3 epsilon chain. Immunoprecipitation experiments showed that this antibody preparation recognised the CD3 antigen on human T lymphoblasts. The antibody stained normal T cells strongly in tissue sections which had been fixed in formalin or Bouin's solution and embedded in paraffin wax. Its reactivity with T cell lymphoma, when evaluated on a series of 96 previously phenotyped cases, closely agreed with the results obtained on cryostat sections. These results indicate that the specific detection of T cells in routinely processed tissue biopsy specimens is now technically feasible on a wide scale in diagnostic laboratories using CD3 peptide antibodies, and they also suggest that in future the use of anti-peptide antibodies may detect other lineage specific antigenic markers in paraffin wax sections.

Amino Acid Sequence↗
PubMed1989

Aberrant phenotypes in peripheral T cell lymphomas.

Seventy six peripheral T cell lymphomas were examined immunohistologically to test their reactivity with a panel of monoclonal antibodies against 11 T cell associated antigens (CD1-8, CD27, UCHL1, and the T cell antigen receptor). Sixty two (82%) lymphomas showed aberrant phenotypes, and four main categories were distinguished as follows: (i) lack of one or several pan-T cell antigens (49, 64% of the cases); (ii) loss of both the CD4 and CD8 antigens (11, 15% of the cases); (iii) coexpression of the CD4 and CD8 antigens (13, 17% of the cases); and (iv) expression of the CD1 antigen (eight, 11% of the cases). No correlation was seen between the occurrence of aberrant phenotypes and the histological subtype. It is concluded that the demonstration of an aberrant phenotype is a valuable supplement to histological assessment in the diagnosis of peripheral T cell lymphomas. It is recommended that the panel of monoclonal antibodies against T cell differentiation antigens should be fairly large, as apparently any antigen may be lost in the process of malignant transformation.

Antibodies, Monoclonal↗
PubMed1989

Novel primary thymic defect with T lymphocytes expressing gamma delta T cell receptor.

Flow cytometric analysis of the peripheral blood mononuclear cells in a six year old girl with a primary cellular immune deficiency showed a normal fraction of CD3 positive T cells. Most (70%) of the CD3 positive cells, however, expressed the gamma delta and not the alpha beta T cell receptor. Immunoprecipitation and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that most of the gamma delta T cell receptors existed as disulphide-linked heterodimers. Proliferative responses to mitogens were severely reduced, but specific antibody responses after vaccination could be detected. A thymic biopsy specimen showed severe abnormalities of both the thymic lymphoid and epithelial component with abortive medullary differentiation and almost an entire lack of Hassall's corpuscles. This patient represents a case of primary immune deficiency syndrome not previously described. Thymic deficiency associated with a high proportion of T cells expressing the gamma delta T cell receptor has been described in nude mice, and it is suggested that the immune deficiency of this patient may represent a human analogue.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

Diagnosis of myelomonocytic and macrophage neoplasms in routinely processed tissue biopsies with monoclonal antibody KP1.

A new monoclonal antibody, KP1, against the CD68 antigen, which labels macrophages and other members of the mononuclear phagocyte lineage in routinely processed tissue sections, has been used to stain a range of lymphoid, histiocytic, and myelomonocytic proliferations. All 20 neoplasms of myeloid, myelomonocytic, and presumed macrophage derivation reacted with antibody KP1. None of the 22 cases of T cell neoplasia had positive reactions. Although 14 of 41 B lineage lymphomas and leukaemias were stained by antibody KP1, staining was usually confined to small dots of reactivity, in contrast to the strong and extensive cytoplasmic staining seen in the neoplasms of myeloid and macrophage/monocyte origin. Furthermore, positive B cell neoplasms were almost all small cell proliferations, which are unlikely to be confused with myelomonocytic malignancies. It was concluded that antibody KP1 is a valuable addition to a panel of monoclonal antibodies for phenotyping lymphomas, particularly in routinely fixed tissues. It should assist the pathologist in the recognition of extramedullary presentation of leukaemia, aid in the diagnosis of suspected cases of true histiocytic neoplasia, and allow for quantitation of macrophages infiltrating lymphomas and other solid tumors.

Antibodies, Monoclonal↗
PubMed1989

The value of lymph node histology in human immunodeficiency virus related persistent generalized lymphadenopathy.

Histological changes in lymph nodes were evaluated in a prospective study of 124 homosexual men who presented with generalized lymphadenopathy. The histological changes were classified according to a classification system with three stages. HIV antibodies were present in 88% of the patients. The finding of one of the three histopathological stages was highly indicative--although not absolutely pathognomonic--for HIV infection. The subsequent course of HIV infection after biopsy was significantly correlated to the histopathological changes, but it was not possible to evaluate if the biopsy added new information to that already available. Among the group of HIV infected, immediate clinical consequences of lymph node biopsy were not observed (95% confidence limits 0-3.3%). In a retrospective investigation of 123 consecutive AIDS patients, it was found that lymph node histopathology had been able to identify secondary infections and neoplasms among 10%. It is concluded that lymph node biopsy is indicated in the HIV infected patients with unexplained generalized symptoms or with atypical enlargement of the lymph nodes. The prognostic significance of lymph node histology compared to other prognostic parameters of HIV infection, remains to be determined.

AIDS-Related Complex↗
PubMed1989

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↗
PubMed1988

Characterization and expression of the human T cell receptor-T3 complex by monoclonal antibody F101.01.

A murine monoclonal antibody (MoAb) F101.01 reacting with the T cell receptor (TCR)-T3 complex is presented. Immunohistological studies showed that F101.01 specifically stains T-zone lymphocytes in lymph nodes, tonsils, and splenic tissue. Two-colour immunofluorescence and flow cytometry demonstrated co-expression of the antigen defined by F101.01 and the pan-T cell antigens defined by CD2, CD3, CD5, and CD7 antibodies. Cells stained with CD4 and CD8 antibodies were both included in the F101.01-positive population, whereas CD16-positive natural killer cells (NK), B cells (CD19 and CD20), and myeloid cells (CD13 and CD33) were excluded. The target antigen of F101.01 co-modulated with the CD3-defined antigen (T3) and the TCR recognized by the MoAb WT-31. CD3 antibody and WT-31 both blocked binding of F101.01. F101.01 precipitated the TCR-T3 complex from lysates of 125I-labelled peripheral blood mononuclear cells (PBMC) and HPB-ALL, when the lysate was prepared with a detergent (digitonin) that conserves the TCR-T3 complex. FACS analysis of T cells from a patient with a T cell immunodeficiency demonstrated that delta-TCS-1-CD3+CD4+ and delta-TCS-1-CD3+CD8+ cells were brightly F101.01+, whereas a large subpopulation of delta-TCS-1+CD3+CD4-CD8- cells were weakly F101.01+. We conclude that F101.01 recognizes a conformational epitope of the TCR-T3 complex and that it reacts with the alpha beta TCR-T3 and the gamma delta TCR-T3 complexes with different intensities.

Antibodies, Monoclonal↗
PubMed1988

Development of cutaneous pseudolymphoma following ciclosporin therapy of actinic reticuloid.

The patient is a 57-year-old man with actinic reticuloid, who despite systemic prednisone, azathioprine, topical steroid, and sun-protective cream had to stay indoors in the summer of 1986. In February 1987 he was started on ciclosporin (CS), 5.5 mg per kg body weight, and skin symptoms did not develop as usual in spring and summer 1987. Following 4 months of successful therapy, he developed an indolent tumor on his right chin and parapsoriasis en plaque on the lower arms and legs. Histological examinations of the tumor showed an intense lymphoid infiltrate of a pseudolymphomatous type. The tumor regressed partly following discontinuation of CS, but additional radiation therapy had to be administered. His clinical symptoms of actinic reticuloid reappeared. Eight months after CS treatment he developed a malignant T cell lymphoma with metastasis in the regional lymph nodes on the neck. CS should not be used in diseases with potential premalignant features even though its therapeutic efficacy in actinic reticuloid was impressive.

Cyclosporins↗
PubMed1988

Immunological characterization and detection of the major core protein p24 of the human immunodeficiency virus (HIV) using monoclonal antibodies.

Eight different monoclonal antibodies (MAbs) were raised against a lysate of the HTLV-IIIb isolate of human immunodeficiency virus (HIV). All eight MAbs recognized the major core protein p24 as well as the gag precursors p39 and p55. Three different epitopes were defined by the eight MAbs when an antigen-catching ELISA was used as the test system. An antigen-catching ELISA for p24 was developed by use of two of the MAbs defining two different epitopes. This ELISA system was applied to the detection of p24 in culture supernatants from lymphocyte cultures of 13 different HIV isolates. The present p24 detecting ELISA proved useful for characterization of different isolates of HIV. Further, two MAbs from the present panel of antibodies were demonstrated to be sensitive and specific probes for the immunohistological detection of p24 protein in tissue sections of lymphoid tissue.

Animals↗
PubMed1988

Expression of segment-specific antigens in the human nephron and in renal epithelial tumors.

The immunohistological staining patterns of several hundred monoclonal antibodies (Mabs) were studied in normal human kidney tissue. Seven Mabs, 3 hematopoietic (F103.12/CD10, MY7/CD13, 3C4/CD15) and 4 non-hematopoietic (LP34, E29, HEA81, HEA125) revealed a segment-specific or pan-nephron staining. The expression of antigens (Ags) labelled by the 7 selected Mabs was then studied in cryostat sections of a series of 43 renal epithelial tumors (31 renal cell carcinomas, 2 oncocytomas, 10 adenomas) in order to correlate the results with the prevailing hypothesis for the histogenesis of these tumors. The adenomas displayed poor expression of CD10-Ag (proximal nephron marker) compared to carcinomas. The chromophobic type of renal cell carcinoma and the benign oncocytoma did not express CD13-Ag, suggesting a possible histogenetic relationship. More than 95% of all tumors simultaneously expressed a proximal and a distal marker. Our results suggest that CD10-antibody may be of value in the distinction between benign and malignant small-sized renal tumors. We conclude that neoplastic transformation may imply such alterations in the expression of marker-Ags (proximal/distal) that no conclusion can be drawn regarding the tubular segment from which a renal epithelial tumor takes its origin.

Adenoma↗
PubMed1988

Ki-1 (CD30) antigen is regularly expressed by tumor cells of embryonal carcinoma.

Ki-1 (CD30) antigen expression has been considered to be restricted to hematopoietic tissues including the recently described anaplastic large cell lymphoma and Reed-Sternberg (RS) cells in Hodgkin's disease. Its presence on some activated lymphocytes in non-neoplastic lymphoid tissues has been used as evidence that such cells might represent the physiologic counterpart of RS cells. In this study expression of CD30 antigen in 117 nonhematopoietic tumors was investigated using monoclonal antibody Ber-H2. The antigen was regularly expressed in frozen section (strongly) and paraffin section (less strongly) by embryonal carcinomas (8 of 10 studied) and the embryonal elements of mixed germ cell tumors (4 of 4), but not in other types of germ cell tumors (0 of 11) or nonhematopoietic tumors (0 of 92). Normal adult, neonatal, and fetal testes were negative for CD30 antigen, as were other fetal tissues and placenta. Ki-1 antibody gives similar results in frozen section. These findings have implications for theories suggesting an origin of RS cells from activated lymphocytes. They are also important for determining the diagnostic significance of CD30 positivity in a tumor of unknown origin, and suggest possible new uses for CD30 antibodies in routine diagnostic immunohistology.

Adult↗
PubMed1987

Distribution of the Burkitt's lymphoma-associated antigen (BLA) in normal human tissue and malignant lymphoma as defined by immunohistological staining with monoclonal antibody 38.13.

The distribution of the Burkitt's lymphoma-associated antigen (BLA) or globotriaosylceramide (Pk antigen) in normal human tissues and in 194 haematopoietic neoplasms was demonstrated by immunoperoxidase labelling of frozen tissue sections with monoclonal antibody 38.13. Staining was seen in most tissues of the body and was most pronounced in the epithelial compartments. In normal lymphoid tissue only dendritic reticulum cells, sinus-lining cells, macrophages and endothelial cells stained whereas lymphocytes were unlabelled. Among neoplasms, BLA was expressed strongly in 4/5 Burkitt's lymphomas. Rather weak expression was seen in 8/120 of the other B-cell lymphomas which included cases of pre-B-stage, mid-stage and secretory-stage B-cell maturation. Expression of BLA was also found in 3/54 T-cell lymphomas (all 3 of activated T-cell phenotype), 1 case of Hodgkin's disease and in 1 case of monocytic sarcoma. We found no correlation between the expression of BLA and any particular surface Ig-type in the B-cell lymphomas. We conclude that BLA is neither a tumour-specific antigen, nor a typical B-cell differentiation antigen. The results concerned with the antigen distribution in human tissues and haematopoietic neoplasms preclude the use of 38.13 as a reagent for diagnosis or specific in vivo immunotherapy of Burkitt's lymphoma.

Antibodies, Monoclonal↗
PubMed1987

Characterization of a monoclonal antibody (BG3C8) that reacts with basal cells of stratified epithelia.

Monoclonal antibodies were produced against a suspension of formaldehyde fixed human epidermal cells. The supernatant fluid of one clone (BG3C8) yielded a bright immunofluorescent staining of basal cells both in cryostat sections of human split skin and in preparations of purified basal cells. As determined by one- and two-dimensional gel immunoblotting of epidermal basal cell proteins the antibody recognized a minor basic polypeptide of 55,000 apparent molecular weight that was not present in extracts of cultured cell lines of epithelial, fibroblast and lymphoid origin. The distribution of the 55,000 molecular weight protein in normal human tissue was determined by immunohistological staining of cryostat tissue sections that included: central nervous, endocrine, female and male reproductive, alimentary, lymphatic-haemopoietic, respiratory and urinary systems, skin and its appendages, mesenchymal tissue (bone, cartilage, muscle, connective tissue, blood vessels, nerves and synovia) as well as placenta and umbilical cord. The results showed a restricted distribution of this antigen which was found only in basal cells of most stratified or pseudostratified epithelia and in myoepithelial cells. This antibody may be useful in the study of normal and pathological differentiation in various epithelial disorders.

Animals↗
PubMed1987

Stages in LAV/HTLV-III lymphadenitis. I. Histological and immunohistological classification.

Lymph nodes from 40 homosexuals with persistent, generalized lymphadenopathy were studied for histological and immunohistological changes and classified into histological stages based on the progressive destruction of lymph node follicles in association with progression of the disease. Three patterns were recognized: stage I was characterized by follicular hyperplasia, mantle zone depletion, and follicular fragmentation in the absence of vasculitis, stage II by signs of follicular involution, and stage III by depletion of follicles and dendritic reticulum cells with development of diffuse pattern. The T zone was gradually depleted of CD4-positive lymphocytes, but on further progression, lymphocytic depletion (which also involved the CD8-positive cells) and fibrosis prevailed. The 40 lymph nodes from homosexuals were classified as stage I in 18 cases, stage II in 11, and stage III in 10. One case did not fulfil our histological criteria for LAV/HTLV-III lymphadenitis, although this patient was seropositive. Convincing correlation was found between histological stages and clinical and laboratory data. The triad of follicular hyperplasia, mantle zone depletion, and follicular fragmentation, in the absence of vasculitis, appears pathognomonic for the early disease. The diffuse pattern, however, may be seen in different disease entities.

Acquired Immunodeficiency Syndrome↗