Immunoenzymatic labeling of monoclonal antibodies using immune complexes of alkaline phosphatase and monoclonal anti-alkaline phosphatase (APAAP complexes)

Inhibition of intestinal macrophage chemotaxis to leukotriene B4 by sulphasalazine, olsalazine, and 5-aminosalicylic acid

Purified intestinal macrophages obtained at resections for colonic neoplasms were investigated for chemotaxis to leukotriene B4 (LTB4) by the Millipore filter assay and leading front technique. Possible inhibition by drugs effective in the treatment of chronic inflammatory bowel disease (sulphasalazine, olsalazine, its active moiety 5-aminosalicylic acid (5-ASA), and the 5-ASA metabolite N-acetylated-5-ASA (ac-5-ASA)) was tested at therapeutic colonic concentrations of 0.01-10 mM. Leukotriene B4 at a dose of 10 nM was equipotent with casein (5 g litre-1) as regards chemoattraction of macrophages. Sulphasalazine, olsalazine and 5-ASA were potent inhibitors of macrophages chemotaxis to LTB4 with IC50 values of 0.43, 0.39 and 0.24 mM, respectively. These concentrations are below the lowest concentration of 5-ASA (2 mM) in the colonic lumen during conventional sulphasalazine treatment of patients with chronic inflammatory bowel disease. The inhibition of macrophage chemotaxis by these drugs may be important for this limitation of the local inflammatory process in chronic inflammatory bowel disease, and may in part explain the beneficial effect of systemic and local treatment with sulphasalazine. Leukotriene B4 appears to be an important inflammatory mediator for the activation of macrophages in colonic inflammation.

Distribution of the CD45R antigen in the maturation of lymphoid and myeloid series: the CD45R negative phenotype is a constant finding in T CD4 positive lymphoproliferative disorders

We have compared the expression of the common leucocyte antigen (CD45) and the restricted leucocyte antigen (CD45R) on normal haematopoietic cells, cell lines, and a total number of 136 cases of myeloid and lymphoid proliferative syndromes. CD45, the conventional leucocyte antigen, presents a generalized distribution along the lymphoid and myeloid maturation pathway with the exception of some myelomas and pre-B leukaemias. In contrast, the expression of the CD45R determinant is more limited. Although it is found in the majority of the differentiation stages of B cells and monocytes, it is present only in the early stages of myeloid differentiation. On T cells it is expressed on mature thymocytes and in the majority of CD8+ lymphocytes and a subset of CD4+ cells on peripheral blood. Finally, our results also indicated that CD4+ T lymphoproliferative syndromes are derived from the CD4+ CD45R- subset (20/20 cases).

Clonal chromosomal abnormalities showing multiple-cell-lineage involvement in acute myeloid leukemia

To determine whether one or more hematopoietic-cell lineages are involved in acute myeloid leukemia (AML), we designed a technique that simultaneously identifies a cell as malignant and determines its lineage. We used numerical clonal chromosomal abnormalities, which are readily detected, to indicate neoplasia, and monoclonal antibodies in an alkaline phosphatase-antialkaline phosphatase detection procedure to identify lineages as granulocytic-monocytic, erythrocytic, or megakaryocytic. Examination of bone marrow from 12 patients with AML showed metaphases of granulocytic-monocytic lineage with abnormal karyotypes in all patients. In seven patients, we also detected abnormal karyotypes in the erythrocytic or megakaryocytic lineage. In all four patients with monosomy 7, both granulocytic-monocytic and erythrocytic cells were affected. Two of four patients with trisomy 8 also had evidence of multiple-lineage involvement, but in two the erythrocytic lineage had normal karyotypes, suggesting an origin at a progenitor-cell stage committed to granulocytic-monocytic development. Multiple-lineage involvement was found in AML both arising de novo (four of five analyzable cases) and following another cancer (three of four analyzable cases). These data demonstrate multiple-lineage involvement in a high proportion of cases of AML and suggest that many cases originate from the multipotent hematopoietic cell or from an earlier progenitor cell.

Demonstration of mononuclear phagocytes in a human epiretinal membrane using a monoclonal anti-human macrophage antibody

Proliferative vitreoretinopathy (PVR), the major complication of rhegmatogenous retinal detachment and posterior segment ocular trauma, is a multistage disease process eventually resulting in traction retinal detachment. The migration of macrophages to a site of disrupted barriers between the vitreous, retina, and choroidea, respectively, is considered to be an important step in the early pathogenesis of PVR. In this study, we demonstrate the presence of numerous mononuclear phagocytes in a human PVR membrane by an APAAP (alkaline phosphatase-anti-alkaline phosphatase) immunostain using a monoclonal mouse anti-human macrophage antibody. This finding correlates with a highly positive fibronectin immunostain in the same specimen. Our results warrant further investigation of the involvement of mononuclear phagocytes in vitreoretinal proliferative disorders.

Color-contrast staining of two different lymphocyte subpopulations: a two-color modification of alkaline phosphatase monoclonal anti-alkaline phosphatase complex technique

A dual staining method for different human lymphocyte subpopulations with nonoverlapping antigen distribution patterns is described. Cytocentrifuge slide preparations of peripheral blood nonadherant mononuclear cells (NAMNC), bone marrow aspirate or buffy coat smears were fixed in acetone and incubated with a primary mouse monoclonal antibody (MAb) against a lymphocyte antigen (CD8, Ig-light-chain, CD19, CD4) followed by rabbit anti-mouse immunoglobulin (Ig) and the alkaline phosphatase monoclonal anti-alkaline phosphatase (APAAP) complex. After repeating the "bridge" antibody and the APAAP, a red product was developed with fast red TR-naphthol AS-BI phosphate. Following this one-color stain the process was repeated using a different primary mouse MAb against another lymphocyte antigen (CD4, Ig-light chain, CD3, MHCII DR, CD5) and fast blue BB-naphthol AS-MX phosphate at the last step to yield a blue product. Control slides stained by the standard one-color APAAP method with the relevant primary MAb showed that there was no nonspecific labelling and the percent of positive cells in a given test was almost identical. To achieve an intense blue in the second stain for some antigens, e.g., CD4, either the MAb concentration had to be increased or two different MAbs recognizing differing epitopes of the same antigen, e.g., T1 and UCHT2 for CD5, were applied. Any change of red to purple at the site of the first stain after 15 min exposure to the blue-yielding AP substrate is due to residual AP activity of the first stain rather than to crossbinding of immunoreagents.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical study of palatal salivary glands of denture wearing patients

The binding pattern of antibodies against different cytokeratin (CK) polypeptides, tissue polypeptide antigen (TPA), carcinoembryonic antigen (CEA), lactoferrin (Lf), lysozyme (Ly) and secretory component (SC) in palatal glands (PSG) of long-term denture wearing patients has been studied to investigate immunohistochemically the localization of these marker proteins in normal PSG and in denture-induced sialadenitis of PSG. The study included palatal gland biopsies from 28 patients (15 f, 13 m; mean age 59 years), 17 of them with normal PSGs, 8 with focal obstructive sialadenitis, and 3 with diffuse sialadenitis. Presence of CK and TPA was found in all intra- and extraglandular salivary ducts, in the basophilic portions of acini, in some mucous acini, and in all atrophic acini. Increased expression of CEA and Lf was observed in inflammed areas of PSG which, on the other site, were devoid of Ly and SC. In the mucous acini of healthy PSG considerable basal Ly immunoreactivity was seen. SC was localized in almost all ductal cells and in some acinar cells. Appearance of Lf in the ductal cells of PSG indicates an early sign of palatal sialadenitis. Some distinctions in the expression pattern of the marker proteins between the mucous acini of major salivary glands and PSG point to differences in the functional activities of either group of salivary glands.

Characterization of the thyroid microsomal antigen, and its relationship to thyroid peroxidase, using monoclonal antibodies

MAb directed to the thyroid microsomal antigen have been developed. All bound to 101- and 107-kD bands in Western blot analysis using thyroid microsomal fraction as antigen. The MAb also bound to microsomal proteins immunoprecipitated by serum from patients having a high titer of anti-microsomal antibody but no antibodies to thyroglobulin or thyrotropin-stimulating hormone receptor. The pattern of binding was related to the amount of reducing agent. The 101- and 107-kD bands were increased by addition of dithiothreitol whereas, in its absence, numerous bands of higher molecular weight were present, suggesting a multimeric protein structure. Despite the inability to immunoprecipitate thyroid peroxidase (TPO) enzymatic activity, the MAb bound intensively in Western blot to denatured purified hog TPO and to denatured immunopurified human TPO. Trypsin digestion of the 101-107-kD antigen produced a doublet of 84-88 kD that was still immunoreactive with MAb. One of five polyclonal sera tested (with a microsomal antibody titer greater than 1/20,480 measured by the tanned red cell hemagglutination technique) also recognized the 84-88 kD trypsin fragments. Addition of V8 protease led to a disappearance of the 107-kD protein, but not the 101-kD protein, proving that this antigen is formed by two different polypeptides. The MAb bound strongly to thyroid epithelium, whereas binding to papillary carcinoma was absent or low and moderate for follicular and Hurthle cell carcinoma. This study indicates that the thyroid microsomal antigen and TPO are identical and are constituted of two different polypeptides. On SDS-PAGE the antigen appears as two contiguous bands which share common epitopes but are not identical, as proven by their size and difference in susceptibility to proteolytic digestion. The immunoreactivity of the molecule is highly dependent on a trypsin-sensitive site, which appears important in the recognition of the antigen by polyclonal sera and may have biological importance. The expression of microsomal antigenicity is variable among various thyroid carcinomas.

Abnormal neutrophils in acute myeloid leukemia and myelodysplastic syndrome

Neutrophils and band forms from patients with acute myeloid leukemia and myelodysplastic syndrome were stained for the presence of myeloperoxidase using a cytochemical method (diaminobenzidine/hydrogen peroxide) and the alkaline phosphatase--anti-alkaline phosphatase immunocytochemical procedure (using monoclonal anti-myeloperoxidase). Neutrophils and bands were also stained for elastase and lactoferrin using monoclonal and polyclonal antibodies, respectively. Subpopulations of neutrophils and bands from cases of acute myeloid leukemia and myelodysplasia exhibited a qualitative and/or quantitative deficiency in myeloperoxidase. In addition, a quantitative decrease in elastase and/or lactoferrin staining was detected. Thus, neutrophils and bands from patients with acute myeloid leukemia and myelodysplastic syndrome have a defect in one or more of the constituents of primary and/or secondary granules. These defects are consistent with the view that abnormal neutrophils and bands are derived from a malignant clone of myeloid precursor cells.

Total absence of eosinophils in a patient with chronic urticaria and vitiligo

A 71-year-old woman with chronic urticaria and vitiligo is reported who lacked eosinophil and basophil leukocytes in her blood, bone-marrow and skin. No IgE was detectable in serum. She had a low level of serum eosinophil cationic protein (ECP) which could indicate that some eosinophils had been formed but rapidly destroyed. There was, however, no ECP release when the patient's serum was mixed with heterologous eosinophils. Staining for eosinophilic proteins in white blood cells by monoclonal antibodies revealed no storage or secreted forms of ECP. The source of ECP in our patient therefore remains unknown.

Pigmented neuroectodermal tumour of infancy: an immunohistochemical study

The pigmented neuroectodermal tumour of infancy is a rare neoplasm of uncertain histogenesis which, in the majority of cases, arises in the maxilla and pursues a benign course. Currently, it would be classified in the group of peripheral primitive neuroectodermal tumours. Histologically it is composed of two principal cell types: neuroblast-like and melanocyte-like. Three typical cases are presented herein, which appear to be the first examined with a panel of antibodies. The neuroblast-like cells labelled positively for neurone-specific enolase but were negative for S-100, neurofilaments, glial fibrillary acidic protein, vimentin, cytokeratin, epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA). The melanocyte-like cells stained positively for neurone-specific enolase, vimentin and cytokeratin but were negative for S-100, neurofilaments, glial fibrillary acidic protein, EMA and CEA. The significance of these findings is discussed in the light of previous suggestions about the differentiation that these tumours show.

Observations favouring Pneumocystis carinii pneumonia as a primary infection: a monoclonal antibody study on paraffin sections

Pneumocystis carinii pneumonia is characteristic of immunodeficiency and the organism is probably acquired during early childhood. Since infection is only manifest in the lungs, it has been presumed that the organism lies dormant in these tissues following the primary infection. Conventional staining procedures have, however, failed in the absence of pneumonia to demonstrate consistently any forms of Pneumocystis carinii. To study this problem further, lung sections and hilar lymph nodes from immunodepressed adults with and without Pneumocystis carinii pneumonia as well as lung sections from presumed immunocompetent patients were examined for the cyst and trophozoite forms of Pneumocystis carinii using a monoclonal antibody. The organism was only identified in areas of pneumonia, and the source of the organism in these patients may therefore be a new infection with a different human subtype and not, as previously thought, reactivation of a primary infection.

Comparison of different methods for enumeration of Langerhans cells in vertical cryosections of human skin

We have quantified Langerhans cells (LC) in cryosections of normal human skin and lesional skin from patients with atopic eczema and psoriasis vulgaris using six different methods. The results from the different methods varied considerably and were sometimes contradictory, for example when LC numbers in psoriatic skin were compared with those in normal skin. Thus, in addition to the staining technique used and the selection of the dendritic cell type to be counted, the enumeration method used can also influence the quantitation of LC in normal and pathological skin.

The immunoglobulin E- and calcium-dependent release of histamine and eicosanoids from human dispersed mastocytosis spleen cells

The clinical features of systemic mastocytosis have been ascribed to mast cell-dependent mediators, but there have been no studies of their release from isolated cells. We have investigated the release of histamine and eicosanoids from isolated spleen cells obtained from tissue of a mastocytosis patient undergoing therapeutic splenectomy. Dispersed cell preparations contained lymphocytes 65.9%, monocytes/macrophages 22.3%, neutrophils 9.9%, mast cells 1.1%, and eosinophils 0.8%; upon challenge with 0.1-3.0 microM A23187 they released histamine much greater than PGD2 greater than TXB2 greater than LTB4 greater than LTC4 approximately equal to LTD4 greater than LTE4. With immunological activation of passively sensitized cells, histamine and PGD2 release had similar dose-response characteristics, but TXB2, LTC4, LTD4, and LTE4 release differed in reaching maximum at 50 micrograms/ml and declining at 125 micrograms/ml anti-human IgE. Percoll centrifugation separated most of the histamine-containing cells to the middle of the gradient, but they were refractory to release with 0.3 microM A23187 or 50 micrograms/ml anti-IgE. Spontaneous release of histamine from these cells was not abnormally high (1.3%-4.5%). Electron microscopy of tissue sections revealed large numbers of mast cells with empty granules. It is possible that the refractory cells observed are such mast cells where intracellular histamine is no longer granule-associated. Most net histamine and PGD2 release was confined to cells at the bottom of the gradients (1.078-1.09 g/ml), although some release of PGD2 occurred near the top (1.05-1.058 g/ml). There was a significant correlation between the net release of histamine and PGD2 with both immunological (r = 0.92; n = 16) and A23187 (r = 0.97, n = 14) activation. These studies provide evidence for a link between PGD2 and histamine release in mastocytosis spleen cells.

Monoclonal glucose-oxidase-anti-glucose-oxidase (GAG) immunosandwich assay for the detection of monoclonal antibodies on routine hematological smears

A murine monoclonal antibody specific for aspergillus niger glucose oxidase has been prepared and used in an unlabeled antibody bridge technique for the detection of monoclonal antibodies. This procedure--the monoclonal glucose oxidase anti-glucose oxidase (GAG) immunosandwich assay--provides excellent immunocytochemical labeling of routine hematological films in combination with optimal preservation of cellular details. In contrast to conventional immunofluorescence procedures, routine hematological films can be used, and these can be stored before and after the immunolabeling. Compared with other immunoenzyme techniques such as those using alkaline phosphatase or peroxidase, the GAG assay is as sensitive and has the advantage that no problems with endogenous enzyme activity are encountered. The availability of alcohol-resistant disclosing reagents allows for routine hematological counterstaining which provides a very clear visualization of both the immunoreaction and the individual morphology of the blood cells.

Immunohistological determination of proliferative activity in seminomas

The proliferative activity and growth pattern of 20 seminomas were determined immunohistologically with the monoclonal antibody Ki-67. A growth fraction of tumour cells between 50 and 80% was found in seminomas with an almost even distribution of proliferating cells in all sections, regardless of tumour size. There was a slight tendency towards a greater growth fraction in tumours at an advanced histopathological stage. No positive correlation could be found between growth fraction and tumour size or lymphocytic infiltration. The results confirm the well known sensitivity of seminomas to radiation and chemotherapy and show that the determination of proliferative activity should be included in the histopathological routine diagnosis of malignant tumours with regard to systemic treatment and prognosis.

Memory B cells in T cell-dependent antibody responses colonize the splenic marginal zones

Specific hapten-binding B cells were identified in the splenic marginal zones following immunization with hapten-protein conjugates. Hapten binding by marginal zone B cells does not appear to be due to passive absorption of anti-hapten antibody. For double immunization with two haptens, 2,4-dinitrophenyl (DNP) and 2-phenyloxazalone (Ox) each conjugated to hemocyanin, resulting in the appearance of discrete DNP-binding cells and Ox-binding cells in the marginal zone. Very few cells were identified which bound both haptens. The hapten-binding cells in the marginal zones have a phenotype characteristic of other marginal zone B cells. They express surface IgM but not IgD. Occasional cells also have surface IgG2c. All hapten-binding cells possessed the antigen recognized by the monoclonal antibody HIS 14 but lacked those identified by HIS24 and HIS22. Hapten-binding B cells were shown to have been in cell cycle shortly before entering the marginal zone but were no longer in cell cycle after arriving at that site. Once in the marginal zone hapten-binding cells were shown to remain in that site for upwards of 2 weeks. Following reimmunization with DNP-hemocyanin, DNP-binding but not Ox-binding cells were lost from the marginal zone. At the same time DNP-binding cells arrived in the periarteriolar lymphocytic sheath and to a lesser extent the follicles. These cells were in active cycle and appeared to give rise both to plasma cells and marginal zone hapten-binding cells. It is concluded that hapten-binding cells found in the marginal zones are memory B cells i.e. they have been derived from B cells which have undergone antigen-driven proliferation, they are no longer in cell cycle but can be induced to re-enter cell cycle by subsequent exposure to antigen. Good antibody responses were obtained following immunization with hapten-polysaccharides; however, no hapten-binding cells appeared in the marginal zones in response to these T cell-independent type 2 antigens.

An automated device for immunocytochemistry

A microprocessor controlled device for automation of immunoenzyme histological and cytological staining procedures is described. As the sequence of processing is controlled by a computer program, the apparatus is flexible and the possibility of technical errors is reduced.

Pitfalls in ecto-5'-nucleotidase enzyme cytochemistry as demonstrated by the immunogold-labelling technique on macrophages

We have used both the enzyme cytochemical method with lead nitrate as a capture agent and an immunological method at the electron microscope level to localize plasma membrane 5'-nucleotidase in rat peritoneal resident macrophages during the initial interactions of latex beads or heat-killed Escherichia coli with the cell during phagocytosis. In macrophages at rest, cytochemical reaction product was evenly distributed along the external surface of the plasma membrane. However, when the cells were phagocytosing latex beads or bacteria, reaction product covered the entire surface of the adhering particles. To determine whether the apparent redistribution of 5'-nucleotidase onto the adhering particle was fact or artifact, we localized 5'-nucleotidase using a monoclonal antibody and an immunogold labelling technique. In macrophages binding or beginning to ingest bacteria, gold particles were distributed along the plasma membrane, except at the sites of cell-bacterium internalization. More significantly, the adhering bacteria were free of gold particles and therefore had no 5'-nucleotidase on their surfaces. Latex beads proved to be unsuitable as a test particle because the gold particles stuck to them non-specifically. We conclude that the artifactual redistribution of lead-phosphate reaction product is a major drawback of enzyme cytochemical methods when used on cell surfaces and that the immunogold labelling technique is more reliable.

Carcinoma of the cervix uteri: an assessment of tumour proliferation using the monoclonal antibody Ki67

Thirty-one cervical biopsies of invasive carcinoma have been studied by immunohistochemical means using the monoclonal antibody Ki67 to determine tumour cell proliferation rates. A wide range (10-50%) in the extent of Ki67 staining (expressed as the percentage of labelled tumour cells) was observed indicating considerable variation on tumour growth rates. There was no significant relationship between the percentage of positive cells and conventional histological parameters such as cell type or tumour differentiation. Immunostaining with monoclonal antibody Ki67 therefore provides a new approach to the assessment of cervical tumour biopsies which will require long term clinical follow-up to establish its prognostic significance.

Large cell lymphoma of bone. A report of three cases of B-cell origin

Clinicopathological and immunohistological features of three cases of large cell lymphoma of bone are reported. On histological grounds, all the cases were diagnosed as histiocytic lymphomas (Rappaport) or primary centroblastic lymphomas, polymorphic subtype (Kiel). On immunophenotyping, malignant cells strongly reacted with the anti-leucocyte antibodies PD7/26 and ROS-220C, thereby indicating their lymphomatous nature, and expressed the B-cell antigens CD19 and CD22. Further studies are warranted to determine whether the B-cell phenotype observed in our cases is typical of the majority of primary large cell lymphomas of bone. Immunohistological analysis with monoclonal antibodies is expected to be of great value not only in defining the immunological phenotype of this rare pathological entity, but also in differentiating it from other neoplasms that involve the skeleton, either primarily or secondarily.

Expression of Leu-8 surface antigen in B-cell lymphomas. Correlation with other B-cell markers

Using in situ immunohistological analysis, expression of Leu-8 and its correlation with other B-cell markers were investigated in 21 selected lymphomas of different categories, each one expressing its own typical immunophenotype. These categories included eight follicular centroblastic/centrocytic (CB/CC) lymphomas, eight intermediately differentiated lymphocytic lymphomas (ILL)/mantle zone lymphomas (MZL), and five lymphocytic lymphomas (LL) associated with chronic lymphocytic leukaemia (CLL). Four reactive lymph nodes and three tonsils were also studied using double immunolabelling procedures. Cell suspensions were also performed in three CB/CC and four ILL/MZL cases. Leu-8 was consistently expressed in ILL/MZL and LL but it was absent in most (7/8) CB/CC lymphomas. In reactive tissues, the Leu-8-positive B cells were strictly confined to the mantle zones. A close association emerged between Leu-1 (CD5) and Leu-8, both being present in ILL/MZL and LL but absent in CB/CC. A consistent lack of association was found between Leu-8 or CD5 antigens and common acute lymphoblastic leukaemia antigen (CD10) and BA-2 (CD9) antigen, whereas Leu-8 and CD5 were strictly associated with surface IgD. Reactivity with Leu-8 provides a means of distinguishing between CB/CC and ILL/MZL. Furthermore, shared immunoreactivity for Leu-8 in ILL/MZL and LL may represent a potential clue to the still uncertain cellular derivation of LL/B-CLL.

Improved avidin-biotin-peroxidase complex (ABC) staining

A considerable intensification of the avidin-biotin-peroxidase complex staining system (ABC) was obtained by sequentially overlaying the sections to be immunostained with an avidin-rich and a biotin-rich complex. Each sequential addition contributed to the deposition of horseradish peroxidase on the immunostained site and allowed the subsequent binding of a complementary complex. With this technique a higher dilution of the antisera could be used and minute amounts of antigen masked by the fixative could be demonstrated on paraffin sections.

Homozygous hypobetalipoproteinemia: a disease distinct from abetalipoproproteinemia at the molecular level

apoB DNA, RNA, and protein from two patients with homozygous hypobetalipoproteinemia (HBL) were evaluated and compared with normal individuals. Southern blot analysis with 10 different cDNA probes revealed a normal gene without major insertions, deletions, or rearrangements. Northern and slot blot analyses of total liver mRNA from HBL patients documented a normal size apoB mRNA that was present in greatly reduced quantities. ApoB protein was detected within HBL hepatocytes utilizing immunohistochemical techniques; however, it was markedly reduced in quantity when compared with control samples. No apoB was detectable in the plasma of HBL individuals with an ELISA assay. These data are most consistent with a mutation in the coding portion of the apoB gene in HBL patients, leading to an abnormal apoB protein and apoB mRNA instability. These results are distinct from those previously noted in abetalipoproteinemia, which was characterized by an elevated level of hepatic apoB mRNA and accumulation of intracellular hepatic apoB protein.

Detection of human white cell proliferative responses by immunoenzymatic measurement of bromodeoxyuridine uptake

The proliferative response of human white cells to stimuli such as foreign histocompatibility antigens or mitogens is traditionally assessed by measuring the amount of [3H]thymidine which the cells can incorporate in culture. In the present paper a new approach is described in which bromodeoxyuridine (BrdUrd) is used in place of thymidine and measurement of incorporation of this molecule is performed by an immunoenzymatic assay (using monoclonal anti-BrdUrd). The procedure avoids the expense, time and hazards associated with scintillation counting, and is simpler to perform. It also appears to be particularly sensitive to low levels of proliferation, and may thus detect such responses more effectively than thymidine incorporation.

Immunohistochemical investigation of collagen subtypes in human glioblastomas

The immunohistochemical distribution of a spectrum of collagens and procollagens was studied in 16 glioblastomas. Anti-collagen IV antibodies frequently outlined thickened or disrupted basement membranes (BM) of tumour vessels. Glial BM were frequently penetrated by tumour cells; endothelial BM were not. Some proliferating vessels did not stain for extracellular collagen IV but were rimmed by collagen IV-positive cells, some of which expressed GFAP. Procollagen I was restricted to proliferating leptomeninges and pathological tumour vessels. Collagen III and procollagen III were codistributed in intratumoural and extratumoural interstitial connective tissue. Collagen VI was most pronounced in the adventitia of normal vessels and in spindle-cell proliferations of pathological vessels but not in the endothelial cell proliferations. On the basis of our findings, we conclude that glial cells play a major role in BM formation around tumour vessels, that procollagen I may serve as a marker for proliferation of interstitial connective tissue, and that the origin of spindle-cell proliferation is adventitial, rather than endothelial.

Dipeptidyl peptidase (DPP) IV in rat organs. Comparison of immunohistochemistry and activity histochemistry

Immunohistochemistry and activity histochemistry were used to study the localization of dipeptidyl peptidase (DPP) IV in rats. For immunohistochemistry, polyclonal as well as monoclonal anti-DPP IV antibodies were employed. The pattern of DPP IV immunoreactivity, determined with polyclonal anti-DPP IV antibody, corresponds to the histochemical pattern found for the enzymic activity of DPP IV. Immunoreactivity was present, in addition, in nerve cells, lateral membranes of certain surface epithelia, e.g., Fallopian tube, uterus and vesicular gland, in the luminal cytoplasm of e.g., vesicular gland epithelium, and in mucous cells of Brunner's gland. The monoclonal antibodies against DPP IV recognized four different epitopes (A-D) of the DPP IV molecule, and revealed that certain epitopes were not detectable by immunohistochemistry in some organs. Generally, the staining intensities for epitopes A, B, C and D decreased in that order. Usually, the monoclonal antibodies against epitopes A and B showed similar reaction patterns to those as obtained with the polyclonal antibody. Epitope D was recognized in the lumen of the duct system of exocrine glands and the intestine. Furthermore, high reactivity of this epitope was detected in goblet cells of the intestine, where no DPP IV activity was present.

Distribution of melanoma specific antibody (HMB-45) in benign and malignant melanocytic tumours. An immunohistochemical study on paraffin sections

The distribution of a recently produced melanoma specific antibody (HMB-45) has been evaluated histochemically on paraffin sections in a large panel of melanocytic and non melanocytic tumours. Results have been compared with the presence of S-100 protein. HMB-45 was shown to be a highly specific antibody being present only in melanomas, junctional melanocytes and histogenetically related neoplasms such as melanocytic neuroectodermal tumour of infancy and, at low levels, on a proportion of peripheral nerve sheath tumours. The high specificity of HMB-45 antibody, coupled with the greater sensitivity of S-100, makes the combined use of these markers practical in the differential diagnosis of skin tumours and of metastatic lesions of uncertain primary site.

Immunophenotype of blast cells in chronic myeloid leukemia

The immunophenotype of peripheral blood blast cells from 14 patients in the chronic phase of chronic myeloid leukemia (CML) was studied using a panel of monoclonal antibodies (McAb) directed against megakaryocytic, granulomonocytic, erythroid and lymphoid antigenic determinants. The blast cells were enriched by a simple bovine serum albumin (BSA) density-cut separation and cooled in liquid nitrogen. The study was done using the alkaline phosphatase-anti-alkaline phosphatase (APAAP) technique on the thawed blast cells. A consistent pattern of reactivity with McAb was found in all patients, showing that blast cells were heterogeneous. A minor component of the blast cells react with platelet antibodies, most of them being labelled with anti-GPIIb-IIIa McAb. Anti-GPIb and Von Willebrand factor McAb detected 4 times fewer megakaryocytic blast cells, suggesting that these cells are located very early in the differentiation scheme. Two major blast cell compartments were labelled with early myelomonocytic (anti-CD13: MY7) and early erythroid (anti-CD36: FA6-152) McAb. The CD34 (My10) and DR antigens which are expressed by immature blast cells and myeloid progenitors of human bone marrow (BM) were present on more than 50% of the CML blast cells. Thus, the blast cells of chronic phase CML patients, showed the same cellular diversity as the increased progenitor cell compartment observed in this disease, and their differentiation stages seemed to be very closely related.

Monocyte/macrophage-directed antibodies Ki-M3 and Ki-M7 detect renal-cell carcinomas

Monoclonal antibodies (MAbs) Ki-M3 and Ki-M7, which detect cells of the human monocyte/macrophage lineages, were tested using immunohistochemistry on a series of benign and malignant human tumors (n = 43). Positive staining was detected in all renal-cell carcinomas (n = 19 positive for both Ki-M3 and Ki-M7), a few cases of breast carcinoma (n = 6 for Ki-M3; n = 2 for Ki-M7), in 1 case each of prostatic carcinoma (Ki-M3) and prostatic adenoma (Ki-M3), and in 1 case of endometriosis (Ki-M3). In normal human kidney Ki-M3 and Ki-M7 reacted with proximal tubules and parts of the distal tubules and with the loop of Henle. The Ki-M3 and Ki-M7 MAbs proved useful in detecting renal-cell carcinomas and in distinguishing these tumors and their metastases from morphologically similar neoplasms: in addition, our study further hints that renal cell carcinomas are derived from tubular epithelial cells.

Does the pleomorphic xanthoastrocytoma exist? Problems in the application of immunological techniques to the classification of brain tumors

A case of a fibrous xanthomatous tumor of the meninges is reported. This is a rare tumor of childhood in which the characteristic pleomorphic histology contrasts with the good clinical prognosis. These tumors were reclassified as pleomorphic xanthoastrocytomas (PXA) due to their glial fibrillary acidic protein (GFAP) positivity. In the present tumor, GFAP was absent from nearly all cell bodies in most of the leptomeningeal regions of the tumor but could be detected with greater frequency at the cortical-leptomeningeal border zones and in the areas in which the tumor had infiltrated the cortex. All the tumor cells expressed vimentin and in, addition, most expressed alpha-1-antitrypsin, alpha-1-antichymotrypsin, tartrate-resistant acid phosphatase, common leukocyte antigen, and OKM1. This spectrum of marker staining corresponded not only to the pattern observed in two cutaneous fibrous histiocytomas and one malignant fibrous histiocytoma, but also to the results previously published in the literature with regard to fibrohistiocytic tumors. By contrast, this spectrum of monocytic-histiocytic marker staining was not seen in gliomas. We, therefore, regard the PXA as a mesenchymal tumor of the meninges, identical to benign fibrous histiocytomas elsewhere in the body. The possible reasons why this mesenchymal tumor can show GFAP positivity in the leptomeningeal border zone are discussed.

Localisation of mRNA and co-expression and molecular forms of GRP gene products in endocrine cells of fetal human lung

The presence of bombesin (gastrin-releasing peptide, GRP)-like immunoreactivity in mucosal endocrine cells of human fetal lung is well established. In this study we have investigated the localisation of pro-GRP mRNA and GRP gene products and compared the distribution and levels of extractable GRP- and C-terminal flanking peptide of human pro-GRP-like immunoreactivity in order to verify synthesis and to investigate their coexistence and molecular forms. Human fetal lungs (14 to 23 weeks gestation) were immunostained, and extracts were assayed using region-specific antisera to pro-GRP. Additional antisera to chromogranin and protein gene product 9.5 (PGP 9.5) were used for immunostaining by the peroxidase anti-peroxidase technique and for double immunofluorescence staining using antisera raised in two species. Immunoreactivity for both bombesin (GRP) and flanking peptide was seen mainly in the same endocrine cells, but more cells were stained with antisera to flanking peptide than with antiserum to bombesin (GRP). In situ hybridisation showed that pro-GRP mRNA was present and thus synthesis of the peptides was taking place. Endocrine cells and nerve fibres were PGP 9.5-immunoreactive, and a subset of cells was immunoreactive for bombesin gene products. Radioimmunoassay and chromatography show that pro-GRP is present in both the uncleaved and cleaved forms, and, in agreement with immunocytochemistry results, that an excess of C-terminal peptide of pro-GRP is detectable. It is therefore concluded that GRP-like peptides and flanking peptide are co-localised in human pulmonary endocrine cells, but the latter is found in larger concentrations than free GRP. Thus GRP-like peptides may be secreted separately from the flanking peptide(s) of pro-GRP.(ABSTRACT TRUNCATED AT 250 WORDS)

Stromal cells in cerebellar haemangioblastomas: an immunocytochemical study

The nature of the stromal cells in formalin-fixed paraffin-embedded material from 23 cerebellar haemangioblastomas was investigated using antisera to intermediate filaments (glial fibrillary acidic protein, vimentin and desmin), histiocytic markers (alpha 1-antitrypsin, alpha 1-antichymotrypsin and lysozyme), glycolytic enzymes (alpha and gamma enolase and aldolase C4) and the endothelial markers, factor VIII related antigen and Ulex europaeus I lectin. Most stromal cells stained positively for vimentin and the glycolytic enzymes. Occasional process-bearing cells within the stroma stained strongly for glial fibrillary acidic protein, alpha 1-antitrypsin and alpha 1-antichymotrypsin. No stromal cell staining for desmin, lysozyme or the endothelial markers was observed, although the latter stained the vascular endothelium within all neoplasms. The findings do not support previous suggestions of an endothelial or histiocytic origin for the stromal cells. They appear to be a heterogeneous population including entrapped reactive astrocytes and locally-derived non-angiogenic cells of neuroectodermal (pial) origin.

Immunohistological demonstration of lymphocyte surface antigens in postmortem lymphoid tissues

The postmortem stability of cell antigens has hardly been studied. Using monoclonal antibodies (mabs) we examined the postmortem detectability of lymphocyte surface antigens in different lymphoid organs by comparing two sensitive, immunohistological staining procedures. To quantify the probable degree of autolysis of the tissues a score system was applied by taking into consideration the postmortem age as well as the core temperature of the corpses. The antigens examined generally proved to be very resistant to autolytic influences. Differences were found when comparing different mabs and with regard to the type of lymphoid tissue. The loss of immunohistological reactions was most extensive in the spleen whereas tonsils showed almost no qualitative alterations in staining patterns. Reactivity of mabs with postmortem tissues decreased in the following order: Dako CD22 and anti-Leu 4, anti-Leu 3a, anti-Leu 7, Dako T8. The mabs anti-Leu 7 and Dako-T8 frequently failed to demonstrate their respective antigens but no correlation between the loss of staining and the degree of autolytic decomposition (our score) could be detected. In general, postmortem tissues as well as tissues shock frozen after delay are suitable for qualitative immunohistology of those cells characterized by the mabs applied. The APAAP-method proved unequivocally to be the superior staining technique.

HLA-DR antigen expression on the thyrocytes of Graves' disease patients

To confirm the expression of HLA-DR antigen on the thyrocytes of Graves’ disease patients and study the relation between the degree of DR antigen expression and clinical or laboratory indices, double immunofluorescence and immunoenzymatic staining were performed on frozen thyroid sections. DR antigen was expressed on the thyrocytes of 8 of 11 patients with Graves’ disease (73%) but not found on the thyrocytes from 6 normal controls. The degree of DR antigen expression had no apparent correlation with the age, duration of the disease, activity of TBII, titers of antimicrosomal and antithyroglobulin antibody. There was no apparent spatial or quantitative relation between lymphoid follicle formation and the DR antigen expression on the thyroid follicles. But DR antigen tended to be expressed on the thyroid tissue with interstitial, lymphocyte infiltration. In conclusion, DR antigen was expressed on the thyrocytes of Graves’ disease patients but the clinical and immunological significance remains to be clarified.

Immunohistochemical detection of antibody in tissue sections of non-perfused and ex vivo-perfused organs using a tetrazolium alkaline phosphatase substrate

We have used nitroblue tetrazolium (NBT) as a color reagent to localize antibody-bound alkaline phosphatase in frozen tissue sections. In the method described, NBT is reduced to a stable black diformazan reaction product that contrasts well with nuclear counterstains such as hematoxylin and stands out strongly in black and white photographs. We have found NBT to be a suitable color reagent for the alkaline phosphatase: anti-alkaline immunohistochemical technique. The reaction product also contrasts well with fast red and can therefore be used as second reagent for two color immunoenzyme studies. In this report, we describe a novel two color immunoenzyme method to assess the ex vivo binding of antibodies against Class II histocompatibility antigens in whole organs connected to a perfusion circuit.

Immunohistochemical detection of HIV structural proteins and distribution of T-lymphocytes and Langerhans cells in the oral mucosa of HIV infected patients

Seventeen biopsies taken from oral mucosa of HIV infected patients were analysed for the distribution of CD4+/CD8+ T-lymphocytes and Langerhans cells. The results were evaluated statistically. An increase in the absolute number of CD4+ and CD8+ cells in HIV infected patients without clinical symptoms, ARC or AIDS was seen in the connective tissue stroma when compared with normal oral mucosa from sero-negative patients. However, the ratio between CD4+/CD8+ cells was decreased due to the disproportionate increase of CD8+ cells. These findings did not show statistical correlation with the clinical status of the infection. In contrast to the increase in absolute number of CD4+/CD8+ cells the number of Langerhans cells was unchanged when compared with the control group. Using four different monoclonal antibodies against virus structural proteins (2 X anti p24, gp41, gp120) two of 26 patients showed labelled cells in consecutive sections in the same connective tissue areas. It was assumed that latently infected mononuclear cells invaded the oral mucosa together with uninfected cells of the cellular immune system.

Immunocytochemical applications in neuroanatomy. Demonstration of connections, transmitters and receptors

In the present paper we review immunocytochemical methods for anterograde tracing with the lectin Phaseolus vulgaris-leucoagglutinin (PHA-L), combined PHA-L tracing - neurotransmitter immunocytochemistry, and the immunocytochemical localization of receptor proteins. These methods will be mainly illustrated by examples from tracing- and neurotransmitter studies on the cholinergic basal forebrain system. The morphology of PHA-L labeled neurons strongly resembles that of Golgi impregnated neurons. The complete axonal trajectories and patterns of presynaptic endings of PHA-L labeled neurons are visualized, both for light- and electron microscopic application. PHA-L-tracing can very well be combined with second immunocytochemical labeling procedures. In this way, traced pathways can be studied in their relation to chemically identified fiber systems or target neurons. Application of immunocytochemistry for the localization of the muscarinic acetylcholine receptor, albeit in its early stages, holds great promise for the near future.

Immunochemical studies of epiretinal membranes using APAAP complexes: evidence for macrophage involvement in traumatic proliferative vitreoretinopathy

Proliferative vitreoretinopathy is characterized by cellular proliferations in the periretinal space resulting in traction retinal detachment. Numerous cellular elements and connective tissue components have been identified by morphologic criteria as well as immunochemical techniques. In this study, we used the recently introduced APAAP (alkaline phosphatase - anti-alkaline phosphatase) immunostaining procedure to identify macrophages, T-lymphocytes, the structural proteins fibronectin, vimentin, and cytokeratin, and a proliferating cell antigen, in eleven human epiretinal membranes obtained during vitreoretinal surgery. Our results confirm that the pathologic processes in PVR are not immunologically mediated, but reveal the features of physiologic wound healing and scar formation. Posttraumatic PVR seems to be characterized by a severe initial inflammatory reaction as evidenced by the presence of numerous macrophages, whereas idiopathic PVR, as a complication of retinal detachment, may be caused by different mechanisms in the early pathogenesis.

Altered expression of collagen type VI in brain vessels of patients with chronic hypertension. A comparison with the distribution of collagen IV and procollagen III

The vascular extracellular matrix (ECM) plays an important role in the histopathology of cerebral microcirculation, but its characterization is still incomplete. For that reason we investigated paraffin-embedded and cryostat sections of intracerebral and meningeal vessels from eight normotensive and six hypertensive humans using monospecific affinity-purified polyclonal antibodies against human/monkey amino-terminal procollagen I + III peptide (P I P, P III P), collagen IV (7-S and NC1 domains), VI, and laminin (P 1 fragment) by applying peroxidase-antiperoxidase- and alkaline phosphatase-antialkaline phosphatase techniques. In normotensives, laminin and collagen IV were codistributed in the basal lamina of meningeal and intraparenchymal vessels. Collagen VI was only present in the adventitia of meningeal vessels and larger intraparenchymal arteries and veins, whereas it was absent from cortical vessels including capillaries. Intensive staining for collagen VI was observed in the choroid plexus, the superficial glia and sheath of cranial nerves. In hypertensives, the basement membrane constituents laminin and collagen IV appeared ubiquitously increased. Here, collagen VI was also deposited in the broadened vascular intima and media of larger arteries and in cortical vessels. In both groups collagen VI and P III P appeared to be codistributed. Our results indicate that significant qualitative change sin ECM of cerebral blood vessels are taking place during the development of hypertension, such as (1) an atypical deposition or an increase of collagen VI which by interconnecting collagen fibrils (I and III) might exert a stabilizing (sclerosing) function in the ECM, and (2) a thickening of vascular basement membranes caused by an accumulation of its major components laminin and collagen IV.

Intra- and extrathymic B cells in physiologic and pathologic conditions. Immunohistochemical study on normal thymus and lymphofollicular hyperplasia of the thymus

Normal thymuses and thymuses with lymphofollicular hyperplasia have been examined immunohistologically using immunoenzymatic single and double labelling methods and a panel of monoclonal antibodies against B lymphocyte differentiation antigens (CD19-, CD20-, CD21-, CD22-, CD23- and CD37ag) and human immunoglobulins (IgM, IgD) for the presence and localisation of B lymphocytes and cells expressing B cell differentiation antigens. The numerous hyperplastic lymph follicles which occur in the pathological condition of lymphofollicular hyperplasia of the thymus were found to originate in the extrathymic compartment of the interlobular septal space. This area was found to be blown up by the growing lymph follicles with exactly the same cellular composition as their counterparts in the peripheral lymphatic tissue. Some of the B lymphocytes expressing the immunophenotype of follicular mantle zone lymphocytes which were detected in the thymic medulla probably infiltrated through discontinuities of the border between the perivascular space and the thymic medulla. Apart from this primarily extrathymic B cell compartment, B lymphocytes and cells expressing B cell antigens were found within the thymus medulla of normal control thymuses of different ages from fetal to adult life. These cells were detected as a small subpopulation in normal fetal, juvenile and adult thymuses. Morphologically they could be subdivided into small, round lymphoid cells accounting for less than 1% of medullary lymphoid cells, and into a larger variant, asteroidally shaped because of short cytoplasmic processes. These asteroid cells were even more infrequent than the lymphoid variant. Immunophenotype (CD19ag+, CD20ag+, CD22ag+, CD37ag+, IgM+, IgD+) and morphology of the first cell type led to the conclusion that the lymphoid cells were in fact B lymphocytes. They were scattered throughout the medulla of fetal and juvenile and adult thymuses alike. The second, the asteroid cell type, constantly expressed CD20ag and inconstantly IgM, CD22ag and CD37ag; furthermore, CD23ag was detected in a subset of the asteroid cells either restricted to the perinuclear zone or expressed in the entire cytoplasma and on the plasma membrane. The asteroid cells were located in the corticomedullary region of the fetal thymuses but were randomly distributed with a tendency to Hassall's corpuscles in juvenile and adult thymuses. They often formed rosettes with non-B lymphocytes.(ABSTRACT TRUNCATED AT 400 WORDS)

The use of the anti-factor VIII method on trephine biopsies of the bone marrow for the identification of immature and atypical megakaryocytes in myeloproliferative diseases and allied disorders. A morphometric study

A morphometric analysis was performed on trephine biopsies of the bone marrow to identify atypical megakaryocyte proliferation following PAS staining and the immunohistological demonstration of factor VIII. This study includes nine patients with a megakaryoblastic crisis in chronic myeloid leukemia (CML), four with acute megakaryoblastic leukemia (AM) and three with myeloid dysplasia later evolving into overt acute leukemia. Comparison and statistical evaluation of the PAS reaction with anti-factor VIII staining reveals that the latter technique not only facilitates the recognition of immature and abnormal megakaryocytes, but leads to a significantly increased count for all megakaryocytic elements in the bone marrow. Thus our retrospective investigation of routinely processed and paraffin-embedded trephine biopsies shows that the diagnosis of a megakaryoblastic crisis in CML as well as AM may be easily established with the aid of the anti-factor VIII method. In all cases of megakaryoblastic proliferation in CML and AM, the appearance of blasts was associated with moderate to pronounced myelofibrosis which could be also determined by morphometry.

Expression of lymphoid-associated antigens on Hodgkin's and Reed-Sternberg cells of Hodgkin's disease. An immunocytochemical study on lymph node cytospins using monoclonal antibodies

The aim of this study was to elucidate the origin of Hodgkin's and Reed-Sternberg cells. Lymph node cytospins and frozen sections from 20 cases of Hodgkin's disease of different histological subtypes were immunostained by the immuno-alkaline phosphatase technique using a panel of monoclonal antibodies. As expected, the Hodgkin's and Reed-Sternberg cells of all cases were positive for the CD30 (Ki-1), CD15 (hapten X) and CD25 (Tac) antigens. In eight cases, a variable percentage of typical Hodgkin's and Reed-Sternberg cells showed a clear-cut cytoplasmic and/or surface positivity for the T-cell-associated antigens CD3, CD5, CD6 and CD4 (seven cases) or CD8 (one case), but consistently lacked B-cell and macrophage-associated markers. The best visualization of T-cell antigens was obtained in cytocentrifuge preparations and in areas of lymph node frozen sections that had been infiltrated by clusters of Hodgkin's and Reed-Sternberg cells. In two cases of Hodgkin's disease (nodular sclerosis, mixed cellularity) the neoplastic cells weakly expressed the B-cell antigens CD19 and CD22, but not T-cell or macrophage-associated markers. In 10 cases, Hodgkin's and Reed-Sternberg cells were negative for all the lymphoid- and macrophage-associated antigens. These results suggest a lymphoid (either T or B) rather than histiocytic origin for the Hodgkin's and Reed-Sternberg cells in a number of Hodgkin's disease cases.