Diagnosis of human lymphoma with monoclonal antileukocyte antibodies

Epithelial differentiation in gliomas, meningiomas and choroid plexus papillomas

The immunohistological findings using antibodies to different intermediate filaments (glial fibrillary acidic protein, vimentin and two types of cytokeratin) and epithelial membrane antigen are described in 89 gliomas, 19 meningiomas and 8 choroid plexus papillomas (CPPs) from adult patients. All the patients had total or subtotal surgical excision of their tumours with clinical follow up for between 3 and 7 years. The immunohistological results were correlated with the histological features and patient survival. Tumours other than low grade astrocytomas, oligodendrogliomas and anaplastic ependymomas expressed one or more epithelial markers. This immunohistological evidence of epithelial differentiation in the absence of histological epithelial features in gliomas confirms that the two are not necessarily correlated. It is concluded that the expression of epithelial markers in some intradural tumours may reflect aberrant differentiation related to the degree of anaplasia in poorly differentiated astrocytomas and glioblastomas. All the patients with anaplastic epithelial marker-positive gliomas died within 1 year, whereas only 68% of patients with marker-negative tumours died within the follow-up period. In ependymomas and meningiomas, the expression of epithelial markers may reflect their histogenesis, while in malignant CPPs such expression could denote either their aberrant differentiation or histogenetic derivation.

Differentiation of round cells in semen by means of monoclonal antibodies and relationship with male fertility

OBJECTIVE

To differentiate round cells in semen samples of subfertile men and evaluate the clinical significance during infertility investigation.

PATIENTS

One hundred and eight randomly chosen couples with a median duration of infertility of 4 (range, 1 to 20) years presenting at the outpatient infertility clinic of the University of Heidelberg, Germany.

MAIN OUTCOME MEASURES

Differentiation of round cells in semen by means of monoclonal antibodies (mABs) and a streptavidin-biotin system for staining. Correlation of results with medical history, outcome of clinical examination, sperm analysis, microbial screening of both partners, evaluation of sperm functional capacity in vivo by means of the postcoital test (PCT) and in vitro with the standardized crossed sperm-cervical mucus penetration test (SCMPT) and the subsequent fertility in a prospective study.

RESULTS

The method used for differentiation of round cells proved to be practical and suitable for routine use. The percentage of leukocytes ranged from 0% to 58% with a median of 3%. Number of round cells and percentage of leukocytes did not differ markedly with regard to andrologic history, clinical findings, for example, varicocele, results of standard sperm analysis, and microbial colonization of semen samples. However, high rates of leukocytes of the round cells correlated with reduced sperm count and morphology and results of PCT. Leukocyte-positive (> 15% leukocytes) specimens were also significantly more frequent in case of inadequate SCMPT and reduced sperm penetration ability in vitro.

CONCLUSIONS

In asymptomatic patients (in terms of genital tract infection), the majority of round cells consist of immature germ cells and < 5% are white blood cells. The streptavidin-biotin system and the mABs used in this study proved to be useful to identify patients with elevated rates of leukocytes in semen possibly reflecting subclinical genital tract infection with influence on sperm functional capacity and subsequent fertility. Thus the procedure can be recommended to be included in a comprehensive evaluation of male fertility.

Immunohistochemical examination of routinely processed bone marrow biopsies

Immunohistochemistry was performed on paraffin sections of 169 bone marrow biopsies fixed in a buffered methanol-formalin solution and decalcified with EDTA. The biopsies included specimens with normal hematopoiesis, and specimens that were affected by various hematological disorders as well as some metastatic carcinomas. The results demonstrate that a wide spectrum of antigens was preserved in routinely processed bone marrow biopsies, even after long-term fixation up to 12 days. Markers for granulopoietic cells were lysozyme, elastase, DAKO-M 1, and MT 1. Megakaryopoiesis was stained with glycoprotein IIIa, von Willebrand factor, and Ulex europaeus agglutinin (UEA), and erythropoiesis with LN 1. Normal lymphocytes as well as lymphoma cells of all non-Hodgkin's lymphomas tested were positive for leukocyte common antigen (LCA), and at variable degree, for MB 1, 4 KB 5, LN 1, LN 2, UCHL 1, or MT 1. Reed-Sternberg and Hodgkin's cells in Hodgkin's lymphomas were reactive with Ber-H 2, LN 2 and Dako-M 1. In plasma cell disorders, staining for immunoglobulin light chains gave best results. Metastatic carcinomas showed predominantly staining with EMA, and KL 1. A selected panel of specific cell markers is proposed, which proved to be helpful in routine bone marrow diagnosis in most cases.

Immunohistological study of grumose degeneration of the dentate nucleus in progressive supranuclear palsy

The grumose degeneration observed in the dentate nuclei of 7 cases of progressive supranuclear palsy (PSP) was studied with a panel of antibodies which included 2 neurofilaments, Tau and ubiquitin. Dentate nucleus neurons were negative with all antibodies except ubiquitin which showed a slightly positive homogeneous pattern of staining. The amorphous material surrounding swollen or normal neurons was strongly positive for neurofilament and subunits and numerous torpedoes were observed in the granular layer of the cerebellar cortex. Our results confirm that grumose degeneration consists in degeneration of terminal axons of Purkinje cells in the dentate nucleus. The positivity of dentate nucleus neurons for ubiquitin may support the concept of synaptic dysfunction between Purkinje cells and dentate nucleus neurons.

Nuclear morphometry of primary B cell thyroid lymphoma

Thyroid lymphoma is usually distinguished from anaplastic thyroid carcinoma and from Hashimoto's thyroiditis by morphological and immunohistochemical assessment of tissue sections. Our objective was to assess the value of nuclear morphometry in the differential diagnosis of these conditions. Nuclear area measurements were performed on 10 cases of thyroid lymphoma using an IBAS 2000 Image Analyser and compared with similar measurements performed on 10 cases of Hashimoto's thyroiditis and 2 of anaplastic thyroid carcinoma. It was found that karyometry demonstrated differences between all three conditions, the cases of thyroiditis being distinguishable from lymphoma on the basis of mean nuclear area alone. Mean nuclear area for lymphomas was greater than for Hashimoto's thyroiditis and lower than for anaplastic carcinomas. The mean nuclear area also reflected the grade of lymphoma, with the exception of one case which had a large reactive T cell population. It is concluded that nuclear morphometry provides valuable information in the diagnosis and assessment of thyroid lymphomas.

Immunophenotype of multinucleated and mononuclear cells in giant cell lesions of bone and soft tissue

AIMS

To compare the antigenic phenotype of giant cells in giant cell lesions of bone and soft tissue with that of osteoclasts and macrophage polykaryons.

METHODS

Formalin fixed, paraffin wax embedded sections of 106 giant cell lesions, 19 granulomatous, and 14 osteoclast containing lesions were immuno-histochemically stained for leucocyte common antigen (LCA), CD68, and HLA-DR.

RESULTS

Osteoclasts and giant cells of giant cell tumour of bone and giant cell reparative granuloma could be distinguished by their generalised absence of HLA-DR reaction from macrophage polykaryons and giant cells in other giant cell lesions of bone and soft tissue. Staining for LCA, CD68, and HLA-DR was useful in distinguishing reactive histiocytic giant cells and osteoclasts from tumour giant cells.

CONCLUSIONS

A panel of macrophage associated antigens should be diagnostically useful in differentiating the histological nature of giant cells in various giant cell lesions of bone and soft tissue.

The role of electron microscopy in the diagnosis of tumours of the head and neck

A four-year study was undertaken to determine the value of electron microscopy in the diagnosis of head and neck tumours. During this period 80 samples were submitted for examination, of which 69 contained assessable tumour. Electron microscopy made a major contribution to the diagnosis in 25 cases (36 per cent). Areas in which ultrastructural examination was of diagnostic significance included the precise categorization of apparently undifferentiated carcinoma and the identification of melanomas. Little diagnostic benefit was gained from electron microscopic examination of thyroid, lymphoid or salivary gland neoplasms. The value of electron microscopy in relation to immunohistochemistry is discussed.

Involvement of major histocompatibility complex class II antigen in Epstein-Barr virus-mediated B cell proliferation

Five MHC class II monoclonal antibodies costimulated proliferation of cord blood leukocytes with Epstein-Barr virus. These agonistic antibodies were of different isotypes, but all of them were either specific for or cross-reacting with HLA-DR. The other MHC class II antibodies, including three that were specific for HLA-DQ and one that was specific for HLA-DP and also those that were specific for MHC class I or leukocyte common antigen, were not costimulatory. The agonistic effect of different MHC class II antibodies was additive, such that costimulation by different antibodies combined significantly exceeded that achieved by either of these antibodies alone. Spent culture media of B cell lines also costimulated B cell proliferation with the virus. Although MHC class II antibodies augmented the effects of suboptimal concentration of the conditioned media, their combined effects did not exceed the maximum costimulation achieved by either the antibodies or the spent culture media alone. These results raised the possibility that MHC class II antigen may contain distinct functional domains involved in the regulation of B cell progression.

Elevated expression of ICAM1 (CD54) and minimal expression of LFA3 (CD58) in epstein-barr-virus-positive nasopharyngeal carcinoma cells

Undifferentiated nasopharyngeal carcinoma (NPC) is a remarkable entity among human tumors because of its constant association with the Epstein-Barr virus (EBV). Malignant epithelial cells harbor the EBV genome and often express at least 2 species of latent EBV protein (EBNA1 and LMP1). Despite the massive presence of tumor-infiltrating lymphocytes, NPC cells obviously escape immune surveillance directed to EBV antigens. Previous investigations carried out on EBV-positive Burkitt lymphoma (BL) cells have shown that this fact may be partially accounted for by a lack of expression of ICAM1 (CD54) and LFA3 (CD58). ICAM1 and LFA3 have therefore been investigated in fresh NPC biopsies and transplanted NPCs. With only 1 exception out of 9 cases, NPC cells appear to express high levels of ICAM1 and low levels of LFA3. This is a complete inversion of the pattern observed in normal epithelial cells in vivo. Additional investigations will be required to determine to what extent these characteristics affect T-cell interactions with NPC cells, specially in the process of EBV-antigen recognition.

An immunohistological study of cartilage and synovium in primary synovial chondromatosis

The antigenic phenotype of cartilage and synovial cells from six cases of primary synovial chondromatosis (PSC) was determined. This was compared with profiles similarly obtained for adult and fetal cartilage cells. The Ki-67 (proliferation-associated) antigen was present on 40-50 per cent of chondrocytes in the proliferative zone of fetal epiphyseal cartilage but absent in chondrocytes of adult articular cartilage and PSC cartilage nodules. The absence of Ki-67 antigen suggests that there were no proliferating cells in the synovium or cartilage in these cases of PSC. In PSC alone, some chondrocytes in the cartilage nodules and mononuclear subintimal cells around the nodules also reacted for CD68, suggesting that growth of the cartilage nodules may occur by a metaplastic process. All synoviocytes in PSC were positive for leucocyte common antigen, HLA-DR, and CD68, a pattern typical of reactive rather than normal synovium.

Clinical and pathological study of two patients with progressive supranuclear palsy and Alzheimer's changes. Antigenic determinants that distinguish cortical and subcortical neurofibrillary tangles

Two cases with classical clinical manifestations of progressive supranuclear palsy (PSP) showed severe progressive dementia as an additional clinical feature. Neuropathological study demonstrated typical features of PSP in the brainstem. Additionally, histological criteria of Alzheimer's disease (AD) were observed. A topographic and immunohistological study (with neurofilament subunit and Tau and Ubiquitin antibodies) of the distribution of neurofibrillary tangles (NFTs) was performed in order to compare the characteristics of NFTs from cortex and brainstem. NFTs from cortex were positive with all antibodies used and were predominantly distributed in cortical layers III and V and affected medium size neurons. Brainstem NFTs were positive only for neurofilament subunits and Tau. Cortical and brainstem NFTs showed immunohistological differences. Cortical NFTs in our two cases had a similar distribution as in control AD cases. On the basis of our observations we believe (1) that cortical tangles in our PSP cases are related to Alzheimer's disease and (2) that the cortical NFTs of PSP and AD are morphologically and immunohistologically distinct. Mechanisms concerned with the production of cortical and brainstem NFTs in PSP and AD are discussed.

Lymphocyte markers on formalin-fixed tissue in Jessner's lymphocytic infiltrate and lupus erythematosus

Clinical and histological differentiation between Jessner's lymphocytic infiltration of the skin (JLI) and lupus erythematosus (LE) may be difficult. Previous immunohistochemical studies using monoclonal antibodies on frozen sections have shown that the majority of inflammatory cells in JLI and LE are T lymphocytes, whereas B lymphocytes are few or absent. We have performed an immunohistochemical study on formalin-fixed, paraffin-embedded tissue sections from seven patients with JLI and five with LE using monoclonal antibodies MT1 (pan T-cells), OPD4 (helper/inducer T-cells CD4), MT2 (mantle zone B and some T-cells), MB2 (pan B-cells), L26 (pan B-cells), and LN1 (germinal centre B-cells). In both diseases, the-majority of the inflammatory cells were T lymphocytes (MT1 positive), confirming the results others have obtained on frozen material. OPD4 positive cells were detected in varying numbers in all cases. However, the percentage of B lymphocytes tended to be higher in JLI than LE. LN1 was the most useful B-cell marker in distinguishing JLI from LE. However, a combination of MT2 and LN1 gave the most significant difference. We conclude that immunohistochemical analysis using a panel of monoclonal antibodies to T and B lymphocytes may be useful in differentiating JLI from LE, although there is still considerable overlap.

Phenotypic characterisation of mononuclear and multinucleated cells of giant cell tumour of bone

Studies were carried out on 3 giant cell tumours of bone (GCTB) to characterise further the cells forming the distinctive mononuclear and multinucleated components. Samples of tumours were grown as explants in vitro and implanted subcutaneously in athymic mice. Cells were characterised in terms of their cell morphology and cytochemical, antigenic and functional phenotype. In culture, giant cells formed a non-proliferative, relatively homogeneous population of cells which expressed features characteristic of the osteoclast phenotype. The mononuclear cell component was heterogeneous and included macrophage-like cells, which persisted for a short time in culture, and fibroblast-like cells which proliferated. In subcutaneous implants, the fibroblast-like cells formed a tissue which included areas of bone formation associated with regions of alkaline phosphatase activity. These observations are consistent with earlier suggestions that the neoplastic component in GCTB consists of a mononuclear stromal cell which elicits a macrophage/osteoclast response.

Neonatal status convulsivus, spongiform encephalopathy, and low activity of Na+/K(+)-ATPase in the brain

The first and second child of a family died from neonatal seizures with no detectable brain malformation, metabolic, infectious, or chromosomal etiology. Neuropathological examination of the brain of the second child who died at 11 days revealed a widespread spongy state and a selective vulnerability of the astrocytes characterized by numerous enlarged bare astrocytic nuclei and different forms of astrocyte degeneration. The glial cells were strongly positive for glial fibrillary acidic protein and vimentin immunocytochemical reaction. Cortical measurement of Na+/K(+)-ATPase revealed very low enzyme activity. We hypothesize that a defect of Na+/K(+)-ATPase of the astrocytes could be the common pathogenetic factor for the congenital status convulsivus and for the spongy state.

Large B-cell lymphoma rich in T-cells and simulating Hodgkin's disease

Unusual clinicopathological features drew our attention to nine of 208 cases diagnosed as Hodgkin's disease. Lymph node biopsy specimens in these cases were immunostained with monoclonal antibodies against B-cell, T-cell and Reed-Sternberg cell associated antigens and epithelial membrane antigen (EMA). Reed-Sternberg-like and other atypical large cells were dispersed in a diffuse, small lymphocyte-rich background, consistent more often with the initial diagnosis of diffuse, lymphocyte predominance Hodgkin's disease. The clinical stage in these cases was unusually advanced (stages III and IV). Splenomegaly was a common feature (six of nine cases), the male to female ratio was 7:2 and the median age was 55 years (range 25-77). Response to recognized regimes for Hodgkin's disease treatment was poor in most cases, and three patients died early of their disease. Large cells were B-lymphocytes expressing EMA--an immunophenotype similar to nodular, lymphocyte predominance Hodgkin's disease. Reed-Sternberg cell and T-cell associated antigens were absent on large cells. Mature T-cells, with nuclear irregularities in some instances, predominated in the background. A more appropriate diagnostic category is, therefore, T-cell-rich B-cell lymphoma. The cases represent a 4-5% erroneous diagnosis of Hodgkin's disease and further suggest that there is a need for revision of criteria for the diagnosis of the diffuse, lymphocyte predominance variant.

Use of monoclonal antibodies to recognise osteoclasts in routinely processed bone biopsy specimens

In decalcified (5% nitric acid) and undecalcified (glycol-methacrylate or resin embedded) routinely processed bone specimens osteoclasts against resorbing surfaces were identified with monoclonal antibodies directed against leucocyte common antigen (LCA) (PD7/26, 2B11), CD68 (KP1), and gpIIIa (Y2/51) but not against HLA-DR (CR3/43 and Ta11B5). Mononuclear cells on resorbing surfaces and occasional mononuclear cells against or near resting surfaces showed a similar pattern of reactivity. This study shows that immunohistochemistry is a sensitive and useful technique for identifying osteoclasts in routinely processed bone specimens. It also suggests a role for mononuclear cells (possibly pre-osteoclasts) in bone resorption.

Phenotyping of immunocompetent cells in normal labial and palatal salivary glands and in non-autoimmune sialadenitis

Different types of inflammatory cells in healthy major and minor salivary glands (SG), including those in labial and palatal non-autoimmune sialadenitis, were quantified immunohistochemically. Plasma cells, mainly IgA type predominated in all SG types, with the smallest number seen in the palatal glands. The numbers of common leukocyte antigen (CLA) reactive lymphocytes were greater in major SGs than in minor ones and were predominantly UCHL1 positive T cell type. Macrophages and neutrophils were absent in palatal glands, rarely present in labial ones and usually present in major SGs. Increases in the number of IgG and IgM plasma cells and lymphocytes (CLA+) which include both UCHL1+ T and L26+ B cell types, were found in non-autoimmune labial and palatal sialadenitis. There was no significant correlation between the number of the inflammatory cells and the degree of glandular atrophy in both labial and palatal non-autoimmune sialadenitis. Increase in their number represents a protective response of these glands in contrast to the inflammatory cells in major autoimmune sialadenitis playing there a pathogenetic role.

Immunohistochemical characterization of multinucleated giant cells in the brain of a Japanese AIDS patient

In an autopsy case of a 35-year-old Japanese hemophiliac with acquired immune deficiency syndrome (AIDS), many multinucleated giant cells (MGCs) were observed throughout the central nervous system. Immunohistochemically, MGCs possessed surface and cytoplasmic macrophage antigens expressed in the late stage of differentiation indicating them to be macrophages in the terminal stage of differentiation. Fine nuclear extensions connecting one nucleus (or lobe) to another were often observed in the MGCs. This feature was interpreted as multilobulation and considered to be a morphological characteristic of MGCs in AIDS encephalopathy. Similarity between MGCs in AIDS encephalopathy and highly lobulated lymphocytes in adult T cell leukemia is discussed.

Differentiation in embryonal neuroepithelial tumors of the central nervous system

Ninety-six embryonal neuroectodermal tumors were studied histologically and immunohistologically with a panel of antibodies including glial, neuronal, epithelial, mesodermal, and myelin markers. In 71 tumors there was glial and neuronal differentiation and expression both of an S (photoreceptor) antigen and vimentin. In five tumors there was only glial differentiation and in 20 tumors only neuronal differentiation. No reactivity for myelin and epithelial markers was found. Histologic and immunohistologic findings identified various degrees of differentiation in different tumors, which was bipolar (glial and neuronal) in most tumors and unipolar in the remainder. The authors suggest that their findings may be the result of normal or aberrant oncogenic differentiation, agreeing with the nomenclature of the World Health Organization classification for these tumors with and the inclusion of a category for ependymoblastoma.

Adult type of leukodystrophy. Krabbe's disease?

A 24-year-old man developed progressive dementia in seven years. The patient suffered a severe bronchopneumonia and eventually died few days later. Brain coronal sections showed a soft gray-brownish discoloration of white matter of centrum ovale but the subcortical arcuate fibers and the interne capsule were preserved. Microscopically, the white matter showed marked loss of myelin and oligodendrocytes, abundant hypertrophic astrocytes and numerous "globoid cells". The latter showed strong positivity in immunostains for a mouse monoclonal antigalactocerebroside antibody. The presence of these cells in the brain white matter might be the morphological basis to classify the present case as one of Krabbe's Leukodystrophy.

Differential effects of CD45 CD45R and CD45R0 monoclonal antibodies in modulating human B cell activation

We have examined the effect of monoclonal antibodies (MoAbs) to different epitopes of the leucocyte common antigen (LCA), CD45, on anti-human immunoglobulin-primed B cell activation. Binding of MoAbs to restricted epitopes present on CD45 glycoproteins of 180 kD and 220 kD (designated CD45R0 and CD45R, respectively) was found to promote B cell proliferation in the presence of T cells. CD45 MoAbs reactive with 'public' determinants on all four constituent members of the LCA family (180, 190, 205, and 220 kD) had either little effect or inhibited the basal B cell response to anti-immunoglobulin priming. Simultaneous immunofluorescent analysis of 5-bromodeoxyuridine incorporation and the expression of CD19 (B cell specific) or CD2 (T cell specific) identified the majority of responder cells as B lymphocytes. CD45R MoAbs significantly enhanced the B cell response to sub-optimal concentrations of interleukin-2. CD45 and CD45R0 MoAbs failed to elicit a similar response. Antibody to the interleukin-2 receptor (anti-Tac) partially blocked the CD45R-driven, T cell-dependent B cell proliferation.

A monoclonal antibody to human leukocyte common antigen, SHL-1, and its use for formalin-fixed, paraffin-embedded tissues

The authors describe a newly characterized murine monoclonal antibody to the human leukocyte surface antigen, SHL-1. The antigen belongs to the leukocyte common antigen (LCA) family, and its molecular weight is about 180,000 daltons, which is similar to that of some previously characterized LCAs. The SHL-1 antigen is resistant to conventional tissue-fixation and embedding procedures. This antibody can therefore be used in the immunohistochemical staining of paraffin-embedded tissue sections. Wide screening with a sufficient number of both fresh and routinely processed paraffin-embedded tissues was done with indirect immunoperoxidase technique. With this procedure, SHL-1 labeled the majority of normal leukocytes and hematopoietic malignancies. Some B-cell malignancies were not stained with this antibody. The non-hematologic malignancies posing diagnostic problems of differentiation from lymphomas or leukemias were completely negative to SHL-1. The immunoreactivity to SHL-1 of samples from 24 leukemic patients and 15 human tumor cell lines was determined by the immunofluorescence method. Of 24 leukemic preparations, 23 were strongly reactive to this antibody. One case of B-cell leukemia did not react with SHL-1. No immunoreactivity was demonstrated in non-hematopoietic tumor cell lines. The overall reaction pattern of SHL-1 proved its usefulness in both diagnostic and research practice in hematological disorders. This antibody detected cell surface antigens of the T cell series more effectively than those of the B-cell series in terms of the positive number of cells and mean fluorescence intensity.

Malignant lymphoma with myxoid stroma: a new pattern in need of recognition

We report a case of malignant lymphoma in the soft tissues exhibiting prominent myxoid stromal changes and cord-like cellular arrangement, mimicking the architectural as well as cytological features of myxoid chondrosarcoma, except for the absence of tumour lobulation. The only clue to the possible lymphomatous nature of the lesion was the past history of lymphoma. Immunohistochemical studies showed that this represented a B-cell lymphoma, staining positively for leucocyte common antigen and five B-lineage markers L26, MB2, B1 (CD20), B4 (CD19) and To15 (CD22). We conclude that malignant lymphoma should not be excluded from consideration when one encounters a myxoid tumour.

Primary large-cell lymphoma of the thymus: a diffuse B-cell neoplasm presenting as primary mediastinal lymphoma

Primary mediastinal nonlymphoblastic non-Hodgkin's lymphoma (NLNHL) has distinct clinical, histologic (diffuse large-cell morphology, often with sclerosis and clear cytoplasm), and immunohistochemical features (predominantly B-cell lineage, usually immunoglobulin-negative), which suggest origin from a unique B-cell population. The thymus has a resident population of B cells with a unique immunophenotype, and can be involved by primary mediastinal NLNHL, in some cases selectively. Fifteen cases of NLNHL involving the thymus were studied by paraffin-section immunohistochemistry using antibodies to formalin-resistant epitopes of B cells (4KB5 [CD45RA] and L26 [CD20]) and T cells (L60 [CD43] and UCHL1 [CD45RO]). All were diffuse large-cell or immunoblastic lymphomas with sclerosis, and were also similar to primary mediastinal NLNHL in clinical features. Neoplastic cells stained with L26 in all but one case, which stained with 4KB5 and an antibody to a leukocyte-common antigen (PD7/26 [CD45RB]), and were uniformly nonreactive with L60 (with one exception) and UCHL1. Intermingled small lymphocytes were uniformly L26-negative and positive for T-cell markers, even in one case with atypia suggesting a lymphoma of mixed morphology. These findings demonstrate that primary thymic and primary mediastinal NLNHL are similar B-lineage neoplasms, and support previous suggestions that both may originate in thymic B cells.

Immunohistochemistry of markers of histiomonocytic cells in malignant fibrous histiocytomas. A monoclonal antibody study

Nine cases of malignant fibrous histiocytomas (MFH) were examined immunohistochemically in frozen sections with six different monoclonal antibodies to histiomonocytic and related cells (EBM11, HAM-56, KB90, antibodies to dendritic reticulum cells, HLADR and LCA). Ten other soft tissue sarcomas, two desmoid tumors, twelve carcinomas, three seminomas and four lymphomas were studied for comparison. All cases of MFH showed positivity for histiomonocytic cell antigens. In six cases, the positive cells could be clearly interpreted to be infiltrating non-neoplastic cells. However, immunoreactivity for multiple histiocytic markers (EBM11, HAM-56, KB90, HLADR) was seen in tumor cells in three cases of MFH. In one of these cases, the positivity could be verified with KP1, an antibody to histiomonocytic cells applied in formalin fixed and paraffin embedded tissue. None of the tumors was positive with the antibody to dendritic reticulum cells or LCA. In the series of non-histiocytic tumors, no cases showed widespread positivity for multiple histiocytic markers. Our results suggest that in relation to true histiomonocytic differentiation MFH might be a heterogeneous group of tumors. The widespread immunoreactivity for multiple histiocytic markers in some cases may indicate a true histiomonocytic differentiation in some MFHs.

Selection of a panel of monoclonal antibodies for monitoring residual disease in peripheral blood and bone marrow of interferon-treated hairy cell leukaemia patients

A panel of monoclonal antibodies (mAbs) directed against B-cell and hairy cell leukaemia (HCL)-associated antigens was used to identify residual hairy cells in the peripheral blood and/or bone marrow samples from 20 patients with HCL, following treatment with interferon-alpha (IFN-alpha) or interferon-beta (IFN-beta). In all cases, hairy cells retained their characteristic phenotype, e.g. positivity for CD22, CD11c, CD25, CD32, and the HCL-associated trimeric protein (t-GP) recognized by the mAbs HML-1, B-ly7, LF61 and Ber-Act8. The most specific marker for identifying a small percentage of hairy cells in peripheral blood cytospins, was t-GP. In alkaline phosphatase/anti alkaline phosphatase (APAAP) stained preparations, t-GP+ hairy cells (provided with large cytoplasm and hairy surface) could be usually distinguished from t-GP+ normal lymphocytes (small-sized cells with smooth surface). In doubtful cases the percentage of residual hairy cells could exactly be estimated by double immunofluorescence staining for CD22 (B-cell marker) and t-GP. The rationale of the test is based on the finding that the small percentage (about 1%) of t-GP+ lymphocytes circulating in the peripheral blood of normal individuals are T-cells of the CD8 subset and not B-cells. The best markers for identifying residual hairy cells in routine bone marrow biopsies were CD45RA (mAb 4KB5) and CD20 (mAb L26). Immunohistological labelling was superior to morphological examination in picking up scattered hairy cells in bone marrow biopsies showing either severe hypoplasia or exuberant hyperplasia of normal haemopoietic series.

Immunohistochemical characterization of inflammatory cells associated with advanced atherosclerosis

During repair of 12 atherosclerotic abdominal aortic aneurysms, fresh samples of aneurysm wall were obtained. Histology confirmed the presence of advanced atherosclerosis associated with medial thinning and a variable aortic adventitial chronic inflammatory cell infiltrate. Monoclonal antibodies were used to identify the inflammatory cells throughout the aortic wall. The majority of lymphocytes in the aortic adventitia were B-cells. B-cells were not present in atheromatous plaques. T-cells, predominantly T-helper cells, were found in atheromatous plaques and in aortic adventitia. The majority of lymphocytes and macrophages in aortic adventitia and most vascular endothelial cells were HLA-DR positive. Ki-67 staining was found in B-cells and T-helper cells, indicating that these cells were proliferating. Occasional lymphocytes were BerH2 positive, indicating that some lymphocytes were activated. These findings suggest that chronic periaortitis is an active, immunologically mediated, local complication of advanced human atherosclerosis.

Brain microglia constitutively express beta-2 integrins

Localization of beta-2 integrins in normal and Alzheimer disease temporal cortex was studied immunohistochemically. Resting microglia were found to express constitutively CD11a (LFA-1), CD11b (Mac-1, CR3), CD11c (P150, 95; CR4), and CD18 (beta-2). They were also found to express constitutively leukocyte common antigen and the immunoglobulin receptor Fc gamma RI. The intensity of expression of each of these antigens was enhanced on reactive microglia in Alzheimer disease tissue. HLA-DR was detected on only a few microglia in control tissue, but was intensely expressed on large numbers of reactive microglia in Alzheimer tissue. These data are consistent with a leukocyte origin and a phagocytic role for microglia. They provide further evidence of an inflammatory response of brain tissue in Alzheimer disease. The microglia were found to make up 9-12% of the total glial population in gray matter and 7.5-9% in white matter.

The application of immunocytochemical techniques to routinely-fixed and stained cytologic specimens. An aid in the differential diagnosis of undifferentiated malignant neoplasms

Routinely-fixed and Papanicolaou stained smears with the cytologic diagnosis of undifferentiated malignant neoplasm that had been prepared with cells obtained by fine needle aspiration biopsy (n = 7), pulmonary lavage (n = 5), or thoracentesis (n = 3) from 15 unselected patients were stained by an immunocytochemical technique to evaluate the presence of keratin proteins and the leukocyte common antigen (LCA). Commercially available, well-characterized monoclonal antibodies with specificities for keratin proteins and the leukocyte common antigen, and a streptavidin-biotin-horseradish peroxidase labelling method were used. Evaluation of the stained smears revealed the presence of one of the two antigens in material obtained from each patient, thus indicating the probable cell-lineage of the neoplastic cells. The specificity of the monoclonal antibody reagents used was further evaluated in routinely-fixed and stained cytologic material from 24 histologically confirmed carcinomas and 12 lymphomas. In conclusion, immunocytochemical techniques may be successfully applied to routinely processed archival cytologic smears to determine the antigenic profile of morphologically undifferentiated cells and therefore aid in the differential diagnosis of undifferentiated malignant neoplasms.

Immunohistochemical characterization of the inflammatory infiltrate in amyotrophic lateral sclerosis

In order to test the hypothesis that the immune system plays a role in the pathogenesis of amyotrophic lateral sclerosis (ALS), the cellular composition of the spinal cord inflammatory infiltrate was analysed in eight cases of sporadic ALS by a panel of monoclonal antibodies. The majority of the many diffusely scattered lymphocytes seen in the anterior and lateral corticospinal tracts and anterior horns belonged to the suppressor/cytotoxicity T-cell subset and were admixed with variable numbers of macrophages. Helper-inducer T-cells were rare and B-cells were conspicuously absent. Compared to controls, ALS specimens exhibited an increase in major histocompatibility complex (MHC) products or human leucocyte antigens (HLA) in the corticospinal tracts and anterior horns. HLA-ABC antigens were expressed in the honeycomb pattern of the glial matrix of the spinal cord, and HLA-DR antigens were strongly expressed by large dendritic cells. In addition, macrophages and endothelial cells were labelled by HLA-DR. These findings suggest that an autoimmune process or infectious agent may play a role in ALS.

Haemopoiesis in human fetal and embryonic liver. Immunohistochemical determination in B5-fixed paraffin-embedded tissues

Paraffin embedded tissue reactive monoclonal antibodies were used to study human embryonal and fetal haemopoiesis, combining optimal morphology with immunohistological determination of haemopoietic cell subtypes and their microenvironment. Seven embryonal and twelve fetal liver specimens were studied, having been fixed in B5-fixative and embedded in paraffin. The different haemopoietic lineages each showed their own immunophenotype and distribution; intercellular and microenvironmental relationships were easily determined. Erythroid cells are reactive with VIE-G4, LN1, and MT1, sometimes partly surrounding a central macrophage. Myelomonocytic cells react with LCA, MT1, MB3, LN2, and anti-lysozyme, and from 14 weeks onwards with LN3. Lymphoid cells show LCA, MT1, MT2, MB1, MB2, MB3, and LN2 reactivity. In a few cases some scarce My10+ early progenitor cells were seen. An important finding is the extensive MT1-reactivity distributed over all haemopoietic lineages, and the demonstration of immature haemopoietic blast cells exclusively expressing the MT1 antigen. Further studies employing MT1 are necessary to delineate the extent of the distribution and the possible function of the antigen. Use of the MT1 mAb may contribute to the elucidation of the exact nature of the haemopoietic blast cells and their place in haemopoietic development.

Characterization of giant cells in Hodgkin's lymphomas by immunohistochemistry applied to randomly collected diagnostic biopsies from the German Hodgkin Trial

A panel of 10 monoclonal antibodies reactive with formalin-resistant epitopes was applied to characterize the giant cells of the Reed-Sternberg, Hodgkin, and lacunar cell types in diagnostic biopsies from the German Hodgkin Trial. The 94 tissue samples examined had been sent to the Reference Center by 44 different laboratories which made the initial diagnoses. A board of four referees re-classified the primary diagnoses established by the 44 different histopathologists, providing subtyping of Nodular Sclerosis according to Bennett et al. (1985, 1989). Only cases with unequivocal agreement among the referees and which satisfied standards of fixation and embedding were included. Giant cells stained positively with: Ber-H2 in 92 per cent (81/88), LN-2 in 86.4 per cent (76/88), and DAKO-M1 in 72.2 per cent (64/88) of cases in which the lymphocyte predominance type was not included. Positive staining was quite rare with the other seven monoclonal antibodies. No significant difference in reactivity was revealed between giant cells of Reed-Sternberg, lacunar or Hodgkin cell types. Approximately one third of the cases were negative for at least one of the markers, Ber-H2, LN-2 or DAKO-M1. The lymphocytic and histiocytic cells in lymphocyte predominance Hodgkin's disease displayed a distinctive staining pattern with positivity for B-cell markers, whereas DAKO-M1 and Ber-H2 were predominantly negative. Finally, we found that randomly collected blocks of primary biopsies permit reliable immunostaining by this panel of monoclonal antibodies, since our results agree with results from the literature obtained from biopsies processed according to more uniform protocols for fixation and embedding.

Interleukin-2 receptor antigen, leukocyte common antigen, and Ki-1 antigen-expressing gastric plasmacytoma. A case report with an immunohistochemical study

A case of primary gastric plasmacytoma expressing various surface and cytoplasmic antigens is reported. With the use of formalin-fixed and deparaffinized sections, 13 different antibodies were applied. Neoplastic plasma cells revealed monoclonal IgG and kappa light chain in the cytoplasm, and expressed epithelial membrane antigen, Ki 67 antigen, cytokeratin, CD 22 antigen, interleukin-2 receptor antigen, leukocyte common antigen and Ki-1 (CD 30) antigen. However, tumor cells were devoid of HLA-DR antigen. These data suggest that the neoplastic plasma cells are at the plasmoblastic stage of maturation and express various surface and cytoplasmic phenotypes.

Malignant histiocytosis. A reassessment of cases previously reported in 1975 based on paraffin section immunophenotyping studies

Malignant histiocytosis (MH) is a term that has been used to describe a syndrome in which there is a systemic proliferation of cells that have the cytologic appearance of atypical histiocytes. Biopsy materials from 15 patients with malignant lymphoma diagnosed as malignant histiocytosis in a previous study reported in 1975 were analyzed by a panel of antibodies and reclassified using current nosologic concepts of malignant lymphoma. The antibodies used comprised reagents detecting a formalin-resistant epitope on B-cells (L26), T-cells (anti-CD3, anti-leu 22 [CD43], and UCHL1 [CD45RO]), monocyte/macrophage-derived cells (KP1 [CD68]), as well as antibodies that detect leukocyte common antigen (PD7 [CD45RB]), and a formalin-resistant epitope of Ki-1 (Ber-H2 [CD30]). The authors found that nine lymphomas had a profile consistent with T-lineage, including six in which Ki-1 (CD30) was coexpressed, and two were B-lineage. Three lymphomas showed no specific lineage characteristics although two were Ki-1 (CD30) positive, and none had expression of KP1 (CD68). The 12 lymph node biopsy specimens showed a variety of patterns of involvement, including sinusoidal, paracortical, and diffuse; the spleens showed predominantly red pulp involvement. A 15th case was believed most consistent with a virus-associated hemophagocytic syndrome. These findings support previous suggestions that the majority of cases diagnosed as MH represent T-lineage-associated hematolymphoid neoplasms, and that only a rare case will be of monocyte/macrophage origin. It is suggested that the term MH be subsumed under the rubric of large cell lymphoma and unless there are compelling immunohistochemical data to support a histiocytic origin, that the term MH be abandoned in favor of a more accurate descriptive term, such as sinusoidal large cell lymphoma.

Production and characterization of a new monoclonal antibody to colorectal carcinoma

This study describes a new murine monoclonal antibody (MoAb) 5C1 raised against human colorectal carcinoma, which gave a differential reaction on formalin-fixed sections of the gastrointestinal tract. The MoAb 5C1 of immunoglobulin M (IgM) isotype reacted with both the cytoplasm and membrane of all normal colonic epithelia, and with all benign colonic polyps and all premalignant colonic lesions. However, there was a decreased expression of the 5C1 antigen in most cases of colonic malignancy and it was this feature that makes MoAb 5C1 unique. The distribution of the 5C1 epitope in normal gastrointestinal tract is limited to a few epithelial cells in the mid-portion of the small intestine but this distribution increased progressively down the digestive tract until it was found on greater than 90% of normal epithelial cells (in membrane and cytoplasm) of the colon. In addition, the 5C1 epitope was present on mucin secreting cells from normal organs of the gastrointestinal, reproductive and pulmonary tract and benign and malignant tissues of the colon. On Western blots, MoAb 5C1 was found to detect a heterogeneous population of molecules with molecular weights greater than 100 kDa with the strongest staining bands found between 230 and 300 kDa. MoAb 5C1 does not detect carcino-embryonic antigens (CEA), human milk fat globules (HMFG), human lymphocyte antigens (HLA) or ABO blood group antigens. The combination of its presence in mucin secreting cells and its broad molecular weight bands suggest that the antigen detected is a mucin.

Variable expression of leucocyte-common (CD45) antigen in CD30 (Ki1)-positive anaplastic large-cell lymphoma: implications for the differential diagnosis between lymphoid and nonlymphoid malignancies

Monoclonal antibodies (mAbs) directed against the leucocyte common (CD45) antigen have been proposed as a useful tool for the differential diagnosis between malignant lymphomas (CD45+) and poorly differentiated nonhemopoietic tumors (CD45-). Thanks to the availability of mAbs directed against fixative-resistant epitopes of the CD45 molecule, this distinction can now easily be made even in routinely processed tissues. However, a small percentage of morphologically poorly defined neoplasms are difficult to diagnose even with the help of immunohistochemistry. The investigators report that 63 out of 165 anaplastic large-cell (ALC) lymphomas did not show any reactivity for the CD45 antigen in paraffin sections. In routine biopsies, the lymphomatous nature of these cases, most of which had been sent for consultation, could be always unequivocally established by demonstrating negativity for cytokeratins (mAb KL1) and clear dot-like and/or surface reactivity with the Ber-H2 mAb, which is directed against a fixative-resistant epitope of the lymphoid cell activation antigen CD30. Strikingly, 54% of the CD45-cases reacted with mAbs directed against fixative-resistant epitopes of the T cell-restricted CD45RO antigen (mAb UCHL1) or the B-restricted molecules CD45RA (mAb 4KB5) and L26 (unclustered). In order to avoid confusion of ALC lymphomas with anaplastic nonlymphoid tumors, pathologists must be aware of the existence of CD30+/CD45- ALC lymphomas, as they can mimic the above-mentioned malignancies both morphologically (due to the sinusoidal growth pattern) and phenotypically (due to the expression of EMA). The investigators conclude that the combined use of mAbs directed against fixative-resistant epitopes of the CD30, CD45RO, CD45RA, and L26 antigens and cytokeratins is essential for the correct diagnosis and treatment of these equivocal cases.

Clinical and neuropathologic findings in a case of severe myoclonic epilepsy of infancy

The autopsy of a 19-month-old boy with severe myoclonic epilepsy of infancy (SMEI) and sudden unexpected death (SUD) revealed several developmental brain abnormalities. The most striking features were microdysgenesis of cerebellum and cerebral cortex and threefold spinal cord channels with surrounding ectopic tissue. Hippocampus and brainstem were normal.

Human epidermal T cells predominantly belong to the lineage expressing alpha/beta T cell receptor

The epidermis of clinically normal-appearing human skin harbors a phenotypically heterogeneous population of T lymphocytes (TCs), the majority of which are CD2+/CD3+/CD5+ "memory" cells, but in an unactivated state, and express the TCR-alpha/beta. In contrast to murine skin, only a very minor subpopulation of CD3+ cells in the human epidermis bears the TCR-gamma/delta. Epidermal TCs primarily are distributed along the rete ridges in the basal keratinocyte layer and are often in close apposition to Langerhans cells (LCs). These TCs were propagated from epidermal cell suspensions after stimulation with TC activating agents (Con A, rIL-1, rIL-2), then evaluated for phenotypic features and TCR diversity. Similar to the in situ situation, most were CD4-/CD8+/TCR-alpha/beta+. In addition, two cultures contained TCR-gamma/delta+ cells; one of these determined to be an adherent CD4-/CD8+ population. Epidermal TCs were significantly (p less than 0.0001) more abundant in the sole than in the other body regions examined (i.e., 40 vs. 7 CD3+ cells/linear centimeter of epidermis) and seemed to have a particular affinity for the acrosyringial epithelium of eccrine sweat ducts. Moreover, the sole usually contained a greater number of CD8+ relative to CD4+ TCs, whereas the epidermal CD4/CD8 ratio in the trunk and extremities was quite variable, although the trend also was towards a slightly larger percentage of CD8+ cells. Collectively, our data suggest that the volar epidermis has a unique microenvironment which is responsible for both the higher density of TCs, preferentially CD8+, and lower number of LCs. This study has not only provided evidence for significant regional variability in the human epidermal TC population of normal skin, but also strengthens the concept for skin-associated lymphoid tissues (SALT), whereby memory TCs recirculate back to the epidermis and interact with resident antigen-presenting cells (i.e., LC).

What's new in the lymphocyte phenotype?

It is a relatively short period of time since the demonstration of surface immunoglobulin by immunofluorescence and the technique of cell surface rosetting first enabled in the identification of lymphocyte subsets. When we now examine the range of monoclonal antibodies which are available to lineage specific and lineage related epitopes the early methods used for the characterisation of normal or abnormal lymphocyte populations seem amazingly crude. The initial development by Kohler and Millstein of techniques for hybridising antibody producing cells to establish continuous lines and their development by large numbers of workers worldwide have provided a vast array of reagents available for cell phenotyping, ranging from the simplest diagnostic determinations to the sophisticated analysis of lymphocyte subsets in development. Indeed, so great is the array of monoclonal antibodies available that the nomenclature has been standardised at four international workshops. The basic aim of these workshops has been to establish a standardised system for the identification of the different monoclonal antibodies available for staining lymphocytes and also to officially allocate antibodies to these groups. A wide range of techniques are employed by the many groups who contribute to these workshops in order to achieve these results. Despite these basic aims, it is also clear that a considerable amount of functional and molecular biological information has come from these large group studies. At the Oxford Workshop, held in 1986, the number of identified "Clusters of Differentiation" (CD) reached the figure 45.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunophenotyping of cutaneous lymphoid infiltrates in frozen and paraffin-embedded tissue sections: a comparative study

A panel of antibodies reactive in routinely fixed, paraffin-embedded tissue sections was compared with a panel of antibodies reactive in frozen sections for the immunophenotyping of cutaneous lymphoproliferative disorders. Three T cell-associated markers (UCHL1, MT-1, MT-2, six B cell-associated markers (MB-1, MB-2, LN-1, LN-2, L-26, 4KB5), immunoglobulin heavy and light chains, anti-LCA antibody, two markers for Reed-Sternberg cells (Ber-H2, Leu-M1), one marker for macrophages (Mac-387) and anti-S-100 protein antibody were tested on normal skin, inflammatory skin diseases, and cutaneous lymphomas and pseudolymphomas. On the basis of the results in frozen sections, 12 inflammatory T cell diseases, 14 T cell lymphomas and pseudolymphomas, and 10 B cell lymphomas and pseudolymphomas were identified. In addition, two cases of specific skin infiltrates of Hodgkin's disease have been examined. Among T cell markers, the greatest sensitivity was exhibited by UCHL1, which stained all but one specimen of T cell infiltrate; it was negative in one specimen of mycosis fungoides that progressed into a T-immunoblastic lymphoma. The combined use of MB-2, LN-2, and 4KB5 identified all B cell proliferations. LN-1 marked germinal centers in all cases of follicular lymphoma and pseudolymphoma. Ber-H2 stained the Reed-Sternberg cells in both cases of Hodgkin's disease and the large cells in the histiocytic type of lymphomatoid papulosis. Mac-387 and anti-S-100 protein antibody recognized macrophages and T-zone histiocytes (Langerhans cells and interdigitating cells), respectively. A panel of antibodies reactive in routinely fixed, paraffin-embedded tissue sections is proposed that facilitates the identification of most B and T cell infiltrates in the skin.

Myelosarcoma without acute leukaemia: immunohistochemical and clinico-pathologic characterization of eight cases

Eight cases of myelosarcoma without acute leukaemia at time of diagnosis were reviewed and biopsies were immunostained using antibodies reacting with myeloid/monocytic markers. Initial tumour location included lymph nodes, paranasal sinuses, nasopharyngeal and/or orbital regions and other extranodal locations. Three cases developed acute myeloblastic leukaemia within 1-9 months. Diagnosis was correct in four of the cases, in the other cases a non-Hodgkin's lymphoma was initially diagnosed. Morphological examination showed a blastic but variable appearance of the tumours. In a few cases cytoplasmic granulation was present. Chloroacetate esterase was present in all cases. In paraffin sections cathepsin G. elastase or lysozyme were present in all cases except one. In frozen material from four of the cases, the myeloid markers CD 11c and CD 33 were present (all cases) and CD 13 and Ki M8 in 3/4 cases.

Diagnosis of primary cerebral lymphoma with particular reference to CT-guided stereotactic biopsy

In establishing the histological diagnosis of primary cerebral lymphoma, stereotactic brain tumour biopsy is the method of choice as the mainstay of therapy is radiation and chemotherapy. This study describes the histopathology and diagnostic immunohistochemistry of 54 primary brain lymphomas in a mainly non-AIDS population. The stereotactic biopsies were performed using the Leksell CT stereotactic frame and a spiral needle which procured about 10-mm-long tissue cylinders. Usually, three successive biopsy cylinders were taken along the target trajectory. Histological examination revealed the prevalence of high-grade non-Hodgkin's lymphoma of the polymorphous centroblastic type. The series did not include any low-grade lymphomas or T-cell lymphomas. L-26 immunohistochemistry resulted in a positive staining of the blasts, thus confirming the B-cell origin of primary brain lymphomas. Small reactive T-lymphocytes and monohistiocytic cells were also found within and at the periphery of the lymphomas and in areas of degeneration. In the biopsies of nine patients, who had shown significant reduction of the lesions on the CT scans, after corticosteroid medication, regressive tissue changes were predominant and consisted of T-lymphocytes, macrophages, and occasionally bizarre reactive astrocytes.

Immunocytochemical Analysis of Lymphoid Lesions Using -Fine Needle Aspiration Biopsy

Sixty-four cases of mainly lymphoid lesions were investigated by fine needle aspiration. Both conventional smears and cytospin preparations were made from this material. Diagnoses based on cytological and immunocytological criteria were made in 57 of these cases and include reactive hyperplasia, non-Hodgkin's and Hodgkin's lymphoma and metastatic carcinoma. Five cases were inadequate for diagnostic purposes and in 2 cases no definite diagnosis could be made. These diagnoses were confirmed using tissue sections in 48/51 cases (with only 3 cytological diagnoses significantly altered by histology) and supported by supplementary clinical information in 8 cases. These results demonstrate the value of FNA biopsy in the investigation of lymphoid lesions using both conventional cytology and immunocytochemistry.

Pancoast syndrome in a patient with malignant lymphoma

Pancoast syndrome is usually secondary to lung cancer. We report a patient with Pancoast syndrome in whom a biopsy specimen of a cervical mass at first thought to be anaplastic carcinoma was found to stain positively for leukocyte common antigen and negatively for keratin, epithelial membrane antigen, and alpha-fetoprotein. A diagnosis of malignant lymphoma associated with Pancoast syndrome was made, and a salutary response was observed after combination chemotherapy. To our knowledge, this is the first reported case of Pancoast syndrome associated with malignant lymphoma. We emphasize the importance of using immunohistochemical stains to define the pathologic condition in difficult cases.

Nodular paragranuloma can transform into high-grade malignant lymphoma of B type

A follow-up study of 537 cases of Hodgkin's disease, lymphocyte predominance type, nodular--designated as nodular paragranuloma (NP)--found simultaneous presence of (n = 11) or subsequent transition into (n = 3) a large cell lymphoma (LCL) in 14 cases. Morphologically, the LCLs were classified in ten cases as centroblastic lymphoma (malignant lymphoma, diffuse, large cell, non-cleaved cell), in three cases as immunoblastic lymphoma (malignant lymphoma, large cell, immunoblastic), and in one case as large cell anaplastic lymphoma. Eleven of the 14 LCLs were studied immunohistologically. Five cases showed a monotypic immunoglobulin (Ig) pattern, seven were positive to the monoclonal B-cell marker Ki-B3, and three showed both monotypic Ig and Ki-B3 positivity. With anti-Ig and Ki-B3, nine of the 11 LCLs could be classified as B-cell non-Hodgkin's lymphoma. Only one case of LCL exhibited the typical phenotype of Hodgkin cells, ie, positivity to anti-CD15 (3C4) and anti-CD30 (Ber-H2). A retrospective follow-up study of these secondary LCLs of B type revealed a longer survival time than that of primary B-type LCLs and other secondary LCLs. These findings indicate that B-type LCL is the most common outcome when NP progresses into a lesion of higher malignancy and provide further evidence of a close relationship of NP to the B-cell system. They also suggest that it would be clinically relevant to distinguish between cases of B-type LCLs secondary to NP and cases of LCLs without association with NP. This implies that signs of a preexisting NP should be looked for when a B-type LCL is diagnosed.

The identification of antigens in antibody/antigen complexes using high performance liquid chromatography

A method for the identification of antigens in a complex mixture of proteins is described. It exploits the effect which addition of a monoclonal antibody and resultant formation of antibody/antigen complexes has on the apparent retention time of the antigen on a size exclusion column. An antigen in the mixture can be identified as that component whose retention time is decreased by addition of its antibody. The principle of the method is demonstrated using an HPLC size exclusion column (DuPont GF450) and three MoAbs, PD7/26, DA6 147 and W6/32 which are directed against three antigens of the lymphocyte surface, the leucocyte-common antigen, class II MHC and class I MHC respectively.