Interdigitating Reticulum Cells Research Articles

Immunophenotypes of Reed-Sternberg cells and their variants: a study of 68 cases of Hodgkin's disease.

Utilizing a panel of monoclonal and polyclonal antibodies, routine paraffin sections in 68 cases of Hodgkin's disease were examined for the presence of immunoreactivity in Reed-Sternberg (R-S) and related cells by the avidin-biotin-peroxidase complex (ABC) technique. In 14 cases of lymphocyte-predominant Hodgkin's disease (LPHD), R-S cells and the polyploid lymphocytic and histiocytic (L & H) variants of R-S cells were immunoreactive for L26 and alpha 1-antitrypsin (alpha 1-AT) in 9 (64%) and 6 (43%), respectively, whereas the remaining antibodies were negative or rarely positive against L & H variants of R-S cells. R-S cells in 24 cases of mixed cellularity Hodgkin's disease (MCHD) were positive with alpha 1-AT in 63% of cases, positive with LN3 in 71% of cases and positive for BerH2 in 92% of cases. The lacunar cell type of R-S cells in 19 cases of nodular sclerosing Hodgkin's disease (NSHD) were reactive for alpha 1-AT in all cases, BerH2 in 18 cases (95%), and LN3 in 17 cases (89%). Pleomorphic variant of R-S cells in 11 cases of lymphocyte depleted Hodgkin's disease (LDHD) showed reactivity with alpha 1-AT in 9 cases (82%), BerH2 in 6 cases (55%), and LN3 in 9 cases (82%). The incidence of L26 in R-S cells was higher in LPHD than in other three subtypes, whereas the immunohistochemical finding of alpha 1-AT had reverse relevance to the result of L26. The incidence of BerH2 in MCHD and NSHD was higher than that of this antibody in the whole of Hodgkin's disease. R-S cells in NSHD and LDHD were highly positive to LN3, and detection rate of these two types was higher than that in the whole of Hodgkin's disease. No cases showed immunoreactivity with anti-T-cell antibodies (CD3, UCHL1 and DFT1), a marker for natural killer cell (Leu7), and a marker for interdigitating reticulum cell (S-100 protein). These results suggest that correlation between predominant staining pattern and R-S cells and variants thereof in each histological subtype of Hodgkin's disease are as follows: LPHD shows L26+, alpha 1-AT-, BerH2-; MCHD and NSHD show L26-, alpha 1-AT+, BerH2+; and LDHD shows L26-, alpha 1-AT+, BerH2+ or L26+, alpha 1-AT+, BerH2-.

Follicular Dendritic Cell Tumors of the Oral Cavity

Follicular dendritic cell tumors are uncommon, and all the reported cases have occurred as primary lymph node tumors. We report two cases in the oral cavity, one in the soft palate and one in the tonsil. The tumors were characterized by sheets, whorls, and storiform arrays of spindly and syncytial-appearing cells with oval nuclei, fine chromatin, distinct nucleoli, and occasional nuclear pseudoinclusions. Multinucleated forms were present and were prominent in one case. An unusual feature was the presence of irregular pseudovascular spaces, which could raise a concern for vascular neoplasm. Because the tumors showed cohesive growth and a sharp interface with the fibrous stroma, they could also be mistaken for carcinoma, sarcoma, or melanoma. After radiation therapy, the palatal tumor showed a greater degree of nuclear pleomorphism, numerous nuclear pseudoinclusions, and striking nuclear grooving and foldings, mimicking interdigitating reticulum cell tumors. The diagnosis in both cases was confirmed by immunoreactivity with CD21 and CD35 and by ultrastructural demonstration of interdigitating cell processes with desmosomes. Both tumors also showed unexpected immunoreactivity with muscle-specific actin. Follicular dendritic cell tumor merits wider recognition of its possible extranodal occurrence as well as its full morphological spectrum in order to better define its behavior.

The Influence of Iodine on the Intensity of the Intrathyroidal Autoimmune Process in Graves' Disease

Several lines of evidence support an etiological role of iodine for the initiation and perpetuation of autoimmune thyroid disease. However, varying relapse rates after increased iodine supplementation have been reported for Graves' disease. Furthermore the effects of iodine on the intensity of human autoimmune thyroiditis have previously only been investigated by indirect parameters and actions of iodine on thyroid function and a possible enhancement of the intrathyroidal autoimmune process in Graves' disease are difficult to separate in previous studies. Moreover lymphocytic thyroiditis in animal models has always been induced by considerably higher iodine doses as those used in in vivo studies. Therefore we investigated the effect of low and high iodine concentrations on the intensity of the intrathyroidal autoimmune process in Graves' disease. The intensity of intrathyroidal infiltration by lymphocytes, memory T cells, plasma cells and antigen presenting cells was determined by quantitative immunohistologic methods in 38 Graves' disease patients. 12 patients received additional preoperative iodine (group II) and 26 were treated with thiourelene antithyroid drugs only (group I). Urinary and intrathyroidal iodine concentrations were determined by a modified cer arsenite method in both groups. Application of high iodine doses in group II induced a significant increase of kappa and lambda positive plasma cells and interdigitating reticulum cells. This was not observed for activated T cells. There was no correlation between the extent of intrathyroidal infiltration by activated T cells, plasma cells and antigen presenting cells, and intrathyroidal or urinary iodine or intrathyroidal iodine concentrations in group I.(ABSTRACT TRUNCATED AT 250 WORDS)

New CD from the B Cell Section of the Fifth International Workshop on Human Leukocyte Differentiation Antigens

This review summaries the expression and the molecular and biochemical characteristics of eight new Clusters of Differentiation (CD79-CD86) established by the B cell Section during the Fifth International Workshop on Human Leukocyte Differentiation Antigens. CD79 monoclonal antibodies (mAb) identify the mbl (CD79 alpha) and B29 (CD79 beta) components of the surface immunoglobulin (Ig) receptor complex. CD80 (B7/BB-1) is a costimulatory molecule that serves as the ligand for two molecules expressed on T lymphocytes, CD28 and CTLA-4. CD81 (TAPA-1) and CD82 (R2) are new members of the tetra-spans family of transmembrane proteins, which include CD9, CD37, CD53 and CD63. These proteins are postulated to be involved in signal transduction. CD83 (HB15) is a marker for human interdigitating reticulum cells, circulating dendritic cells and Langerhans cells. CDw84 and CD85 are new B cell-associated molecules that are also expressed by monocytes. CD86 is a new B cell activation antigen.

Histopathologic patterns of erythema migrans and borrelial lymphocytoma

Erythema migrans and borrelial lymphocytoma are early signs of Lyme borreliosis. After infection with Borrelia burgdorferi via a tick bite, the body undergoes a series of events in an attempt to destroy the microorganism or limit its spread to other sites. Biopsies taken from patients soon after a tick bite show the tick head and neighboring skin with edema, vascular dilation, extravasation of erythrocytes, and an inflammatory infiltrate of neutrophils and eosinophils. If the spirochetes persist in the skin, the infiltrate shows predominantly lymphocytes and, in many circumstances, plasma cells. The infiltrates in the early phase of the disease are histologically characterized by the presence of both B and T lymphocytes (helper and suppressor phenotypes), macrophages, interdigitating reticulum cells, mast cells, and plasma cells. After dissemination, B. burgdorferi appears to cause direct organ damage or to provoke immune mechanisms resulting in inflammation. 1

Cathepsin E in follicle associated epithelium of intestine and tonsils: localization to M cells and possible role in antigen processing

A specific rabbit anti-human serum was used selectively to localize the aspartic proteinase cathepsin E to follicle associated epithelium (FAE) of human and rat intestine, including jejunum, ileum, appendix, colon and rectum, as well as of human palatine, pharyngeal and lingual tonsils. Coexpression of class II histocompatibility antigen HLA-DR antigen has been observed in some of the cathepsin E-positive epithelial cells. In addition, cathepsin E has been detected in a few mononuclear cells of intestinal lymphoid structures and tonsils resembling interdigitating reticulum cells of lymph nodes. Another aspartic proteinase, cathepsin D, has been found to be poorly represented in FAE and intensely expressed by macrophages. Electron immunocytochemistry localized cathepsin E to endosomal vesicles and endoplasmic reticulum of M cells in rat and human ileum as well as of M-like cells in human palatine tonsil. The results suggest a possible role of endosomal cathepsin E in the processing of macromolecules and microorganisms transported by M cells and related epithelial cells to mucosal associated lymphoid tissue (MALT).

Cytokine (Interleukin-1 alpha, Interleukin-1 beta, Tumor Necrosis Factor alpha, and Interleukin-6)-Possessing Cells in Lymph Nodes of Malignant Lymphoma

Interleukin (IL)-1 alpha, IL-1 beta, tumor necrosis factor (TNF) alpha, and IL-6 are the most important triggers in the response of the immune system to infection and neoplasia. We examined the histochemical distribution of cytokine-possessing cells in neoplastic lymph nodes of 68 malignant lymphomas. The HLA-DR positive interdigitating reticulum cells (IRCs), histiocytes/macrophages (H/Ms) and epithelioid histiocytes with these cytokines were frequently encountered in Hodgkin's disease, B cell lymphoma of lymphoplasmacytic/cytoid, centroblastic and immunoblastic types, and T cell lymphoma of Lennert's and anaplastic large cell types. In almost all cases of B cell lymphoma of chronic lymphocytic leukemia, centrocytic, follicular centroblastic/centrocytic, Burkitt's types and T cell lymphoma of lymphoblastic, angioimmunoblastic lymphadenopathy and pleomorphic types, the cytokine-possessing cells were rarely or occasionally present. These lymphomas with less cytokines had also few or occasionally encountered IRCs, while H/Ms were frequently or occasionally present. Well-developed dendritic reticulum cells in some types of lymphoma had few cytokines. The population of cytokine-possessing cells was related with histologic type of lymphoma and the volume of IRCs. The IRCs might act as an important initiator of reactive cells against tumor cells. In addition, neoplastic T cells influenced the cytokines' possession of IRCs and H/Ms. Although lacunar, Hodgkin's and Reed-Sternberg cells in Hodgkin's disease and the neoplastic cells in peripheral T cell lymphoma showed weak positive reaction of TNF alpha in one third of the cases, lymphoma cells in the majority might have few cytokines, especially IL-1s and IL-6.

TNF Receptor Distribution in Human Tissues

The nature and location of cells responding to tumor necrosis factor-alpha were investigated in situ by immunohistochemistry using monoclonal antibodies directed against the p75 and p55 proteins of the TNF receptor. Receptor expression was found in the thymus and secondary lymphoid tissues. In the thymus, the p75 receptor was confined to medullary lymphoblasts and dendritic cells, which costain with the Tac protein of the interleukin-2 receptor. In lymph nodes and other secondary lymphoid tissues, the p75 receptor was expressed on activated lymphocytes and interdigitating reticulum cells of the T cell areas, whereas the p55 receptor was confined to the germinal center dendritic reticulum cells, which are the main site of TNF-alpha production. TNF receptor proteins were up-regulated in reactive hyperplasia together with increased TNF-alpha expression. Surprisingly, no TNF-R was detectable on nonlymphoid tissues. The species specificity of these TNF-antibodies was high: whereas the antibodies cross-reacted with epitopes in nonhuman primates, no immunoreactivity was detected in lower animal species, e.g., dog, rabbit, and rodents. The data presented suggest that TNF-alpha, which is produced by germinal center DRCs, might regulate an in vivo immune response through autocrine and paracrine pathways, e.g., through the p55 and p75 receptor proteins, which are expressed at different sites on the lymphoid tissue.

A novel cell-surface molecule expressed by human interdigitating reticulum cells, Langerhans cells, and activated lymphocytes is a new member of the Ig superfamily.

cDNA isolated from a human lymphocyte library were analyzed and shown to encode a novel cell-surface glycoprotein, termed HB15, expressed by dendritic cell subsets and activated lymphocytes. The predicted mature 186 amino acid protein was composed of a single extracellular V-type Ig-like domain, a transmembrane region, and a 39-amino acid cytoplasmic domain. In contrast to most Ig-like domains, analysis of a partial genomic DNA clone revealed that the extracellular Ig-like domain of HB15 was encoded by at least two exons. Northern blot analysis revealed that HB15 derived from three mRNA transcripts of approximately 1.7, 2.0, and 2.5 kb expressed by lymphoblastoid cell lines. Two mAb reactive with HB15 were produced and used to show that HB15 is expressed as a single chain cell-surface glycoprotein of M(r) 45,000. HB15 expression was specific for lymphoblastoid cell lines and mitogen-activated lymphocytes, and HB15 was not expressed at detectable levels by circulating leukocytes. Immunohistologic analysis revealed that HB15 had a unique pattern of expression, being found predominantly in hemopoietic tissues with strong expression by scattered interfollicular interdigitating reticulum cells and weak expression by germinal center cells. HB15 was also expressed by Langerhans cells within the skin. HB15 therefore serves as a unique marker for the subset of dendritic cells represented by Langerhans cells and interdigitating reticulum cells. Thus, the HB15 glycoprotein represents a newly identified member of the Ig superfamily that may play a significant role in Ag presentation or the cellular interactions that follow lymphocyte activation.

One-step double immunolabeling of mouse interdigitating reticular cells: simultaneous application of pre-formed complexes of monoclonal rat antibody M1-8 with horseradish peroxidase-linked anti-rat immunoglobulins and of monoclonal mouse anti-Ia antibody with alkaline phosphatase-coupled anti-mouse immunoglobulins.

A novel one-step double immunolabeling method was elaborated on the basis of the simultaneous application of preformed molecular complexes of two primary antibodies with their specific secondary antibodies labeled with different enzymes. Treatment with a rat monoclonal antibody (MAb), M1-8, pre-coupled with horseradish peroxidase-linked sheep anti-rat immunoglobulins, and enzyme reaction revealed by the 3-amino-9-ethylcarbazole/hydrogen peroxide reaction, resulted in red-brown intracytoplasmic staining of interdigitating reticular cells in the lymph nodes of Balb/c mice. Another molecular complex, made of mouse anti-Ia MAb with alkaline phosphatase-linked rabbit anti-mouse immunoglobulins, applied at the same time and then developed with naphthol AS-BI-phosphate/fast blue BB as substrate, yielded blue surface staining of this cell type in addition to labeling of B-lymphocytes. The method described provides the possibility of relatively rapid double antigen detection where the binding sites of the secondary antibodies are saturated by the specific primary immunoglobulins. This approach seems to avoid nonspecific binding of primary antibodies to Fc receptors, and the unwanted binding of secondary antibodies with cell surface immunoglobulins on B-lymphocytes or with crossreactive primary antibodies used in the other sequence, if the primary antibodies and the tissue are the same or crossreactive animal species.

Immunological studies in giant cell arteritis

The results of investigations on the humoral immunological mechanisms are conflicting in giant cell arteritis (GCA) and have not been able to explain the pathological findings in the inflamed arterial wall. Altogether, immunological studies suggest that a cell-mediated immune reaction, possibly against an autologous antigen, occurs locally in the arteritic lesions of GCA. The excellent effect of treatment with glucocorticosteroids on the inflammation in GCA can also be explained by this model. The glucocorticosteroids inhibit the synthesis of interleukin-1 (IL-1) by the macrophages and suppress the IL-2 production from the T cells (Palacios, 1982). The observed HLA-DR expression in the arterial wall can be accounted for by the sum of macrophages and activated T cells, the macrophages being the most probable antigen-presenting cells. The interdigitating reticulum cells observed in some of the GCA patients may also be involved in antigen presentation. What the antigen(s) may be is, however, still unknown, as are the factors initiating the inflammatory process. It has recently been possible to extract T lymphocytes from the inflamed tissue and to culture these cells in vitro. After culture, it is possible to study the gene for the T-cell receptor, and probably even the antigenic specificity of the T cells. I hope that this approach may lead to a better understanding of the pathogenic mechanisms in GCA.

Immuno- and Enzymehistochemical Characterization of ‘Plasmacytoid T-Cells’ in Formalin-Fixed Paraffin-Embedded Tissue of Reactive Lymph Nodes

In eight (10.4%) of 77 randomly selected cases of lymphadenitis, foci of 'plasmacytoid T-cells' (PTCs) were found. We characterized the PTCs in formalin-fixed paraffin-embedded tissue by immuno- and enzymehistochemical techniques. In each case the PTCs formed nodular and patchy infiltration patterns around the high endothelial venules in the paracortex of the lymph nodes. The PTCs in half of the cases were present near the intermediary peritrabecular sinuses. The PTCs were found to be positive for CD 45 (LCA), CD 45 R (4 KB 5) and CD 43 (MT 1), but not for CD 45 RO (UCHL 1), L 26 (CD 20), myeloperoxidase, naphthol AS-D chloroacetate esterase, Mac 387, alpha-1-antichymotrypsin or S 100 protein and anti-dendritic reticulum cell antibody. Some lysozyme+ PTCs were mingled in and around the foci in each case. In five cases the PTCs showed weaker positive reactions for CD 68 (EBM 11) and HLA-DR than for T-zone macrophages and sinus histiocytes. Related to the degree of desintegration of the nodular PTC-foci increasing numbers of T- and B-lymphocytes, T-zone macrophages and interdigitating reticulum cells with HLA-DR were detected in the foci. In two cases, where there was no HLA-DR expression by PTCs, small amounts of HLA-DR in secondary lymph follicles and a decrease of HLA-DR+ T-zone macrophages and interdigitating reticulum cells were observed. Our results suggest that there is a high degree of interaction between PTCs and other cellular components in the lymph node. The PTC may represent a special type of resident macrophage with secretory capacities.

Estudio Histoquímico e Immunohistoquímico del Tejido Linfoide Porcino: Ganglio Linfático, Bazo y Timo

Immunohistological (S-100, cIg) and enzyme histochemical (ANAE/ANBE, beta-glu, ATPase, AcP) investigations were carried out to identify lymphocyte and reticular cell subpopulations "in situ", in pig lymphoid tissue (lymph node, spleen, and thymus) of a 6 months old group, and a 6-9 days old one. By means of immunohistological techniques, in the 6 month old pigs we could detect S-100 protein (PAP), chiefly in T-areas lymphocytes, but we also found some S-100 positive lymphocytes in spleen follicles. Also S-100 protein were detected at Follicular Dendritic Cells (FDC) in lymph node and spleen; and Reticular Fibroblastic Cells (RFC) only in the first one. Finally, S-100 were noted in Hassall corpuscles (thymus), nervous fibres, and endothelial cells too. Using PAP (IgG, IgM) and IPI (IgA) techniques we could detect lymphocyte cytoplasmatic surface immunoglobulins (cIg) in lymphocytes, lymphoblastoid and plasmacytoid cells in nearly all tissue compartments. By means of histochemical techniques we could identify T-area lymphocytes ANAE/ANBE and beta-glu positives (cytoplasmatic spots) and B-area lymphocytes ATPase positive; macrophages, and polymorphonuclear eosinophiles PHNE being ANAE/ANBE and beta-glu positives (diffuse cytoplasmic stain); and Hassall corpuscles ANAE/ANBE and AcP positives. Concerning to reticular cells, we found FDC and RFC in lymphoid follicles, and Interdigitating Reticular Cells (IDC) in lymphoid diffuse tissue, with enzyme activity (all the enzymes studied) in nearly all the cases. In piglets, the immunohistological and histochemical pattern was nearly the same.

The Lewis X antigen. A new paraffin section marker for reed–sternberg cells

Using a monoclonal antibody specific to the Lewis X antigen (anti-Lex), the authors studied 103 cases of Hodgkin's disease (HD) in comparison with 57 cases of non-Hodgkin's lymphoma (NHL); three cases of granulocytic sarcoma (GS); two cases of malignant histiocytosis (MH); one case of monoblastic leukemia (ML); one case of interdigitating reticulum cell sarcoma (IRCS); six cases of histiocytosis X (HX); one case of reticulohistiocytoma (RH); 44 various reactive conditions of the lymph node (LN). Reed-Sternberg and related (R-S) cells stained selectively in 80 of 92 cases of HD (87.0%), excluding 11 cases of lymphocyte predominance type. The stain was better in B-5-fixed specimens than in formalin-fixed specimens, showing a dense deposit of reaction products at a paranuclear site and on the cell surface. The staining results were compared with those of Leu-M1 and found to be superior both qualitatively and quantitatively (detection rate of R-S cells: 87.0% versus 68.5% of Leu-M1). Granulocytes, rare epithelioid histiocytes, and some endothelial and/or erythrocytes also stained with anti-Lex. The stain had positive results in three cases of GS showing a diffuse cytoplasmic staining pattern. Of NHL, two of 29 peripheral T-cell lymphomas stained to show rare paranuclear deposits without cell surface staining. The stain had negative results in MH, ML, IRCS, HX, and RH. Of 45 reactive LN, minute subcapsular collections of Lewis X+, altered-appearing Langerhans'-like cells, were observed in all ten LN from human immunodeficiency virus (HIV)-associated persistent generalized lymphadenopathy (PGL). The stain had negative results in all other various reactive conditions of LN. In conclusion, Lewis X staining is useful as a marker for R-S cells in paraffin sections with staining results superior to those of Leu-M1. Lewis X staining also detects subcapsular clustering of altered-appearing Langerhans'-like cells in PGL, which has not been described previously and warrants additional study.

Interdigitating reticulum cells in human renal grafts

Seventeen human renal graft biopsies taken 1 h to 50 days after transplantation and 3 human renal non-graft biopsies (2 minimal change and 1 non-tumour portion of angiomyolipoma) were investigated with immunoelectron microscopy in order to identify interdigitating reticulum cells (IDC) or dendritic cells (DC) in renal tissues. The antibodies used consisted of a rabbit polyclonal antibody of antihuman S100 beta protein, mouse monoclonal antibodies of antihuman HLA-DR, anti-CD3, and anti-CD1a. IDC or DC were identified in 11 renal grafts. They were found both in the glomerular and interstitial (peritubular) capillary lumens but not in the interstitium of 1 case: both were present in the interstitial capillary lumens and interstitium of another case, and in the interstitium only of 9 cases. In the remaining 6 grafts and 3 non-grafts they were not detected. These 6 grafts and 3 non-grafts did not show any pathological change except for foot process fusion of the glomerular epithelia in 2 cases of minimal change. These findings suggest that IDC or DC are not normally present in human renal tissues. The presence of the cell in the glomerular and peritubular capillary lumens of a biopsy taken after 1 h and their presence in the interstitial capillary lumens of another graft biopsy, suggest that the IDC or DC in human renal grafts are derived from recipients, not donors, and that they migrate from the circulating blood toward the interstitium.

The nature of Hodgkin and Reed-Sternberg cells, their association with EBV, and their relationship to anaplastic large-cell lymphoma

This review focuses on the cellular origin of Hodgkin and Reed-Sternberg (HRS) cells, their association with the Epstein-Barr virus (EBV), and their relation to Ki-1+ anaplastic large-cell (ALC) lymphoma. The tingibility of HRS cells in paraffin sections for polyclonal immunoglobulin represents a staining artifact and thus can no longer serve as an argument for the histiocytic nature of HRS cells. Immunolabeling studies do not support the putative relationship of HRS cells to cell types such as macrophages or interdigitating reticulum cells, but instead suggest: a) that lymphocyte-predominant (LP) Hodgkin’s disease (HD) represents a B-cell neoplasm which is distinct from non-LP HD, and b) that non-LP HD constitutes a syndrome rather than a disease entity, with the existence of T-cell types and B-cell types. HRS cells (and the tumor cells in ALC lymphomas) frequently display an immature genotype in association with late activation markers, leading to the assumption that the tumor cells in many cases of HD (and some cases of ALC lymphoma) may be derived from immature lymphoid cells that are infected by a virus that superimposes characteristics of mature activated lymphocytes on these cells. Southern blotting, in situ hybridization, and polymerase chain reaction (PCR) experiments revealed an association of EBV with HRS cells in a significant proportion of HD cases, suggesting that EBV may be responsible for the dissociation between genotype and phenotype in HRS cells, because EBV is a strong inducer of the activation antigens CD30 and CDw70. While clear-cut morphological and immunohistological differences between Ki-1+ ALC lymphoma and HD have not yet been found, the comparison of chromosomal aberrations observed in Ki-1+ ALC lymphoma and HD disclosed differences supporting the view that these two tumors are separate entities.

リンパ節およびひ臓内Ｔ領域における樹状細胞の免疫組織化学的研究

Langerhans cells (LCs) in the epidermis and interdigitating reticulum cells (IDCs) in the lymph nodes are said to have the same morphological and immunological characteristics. In this paper, we examined LCs and IDCs in the superficial (cervical and inguinal), hilar and mesenteric lymph nodes, and also spleens, using anti S-100 protein and OKT-6 antibodies for immunostaining. Lymph nodes and spleens taken from 16 autopsies were used for the experiments. We were able to observe LCs which were positive for both anti S-100 protein and OKT-6 in the superficial and hilar lymph nodes. However, we could not find LCs in the mesenteric lymph nodes or spleens. The immunological and morphological features of LCs were similar to those of veiled cells in the marginal sinus possibly moving from the skin to the T-zone of the superficial and hilar lymph nodes. OKT-6 positive cells were not exactly identical with anti S-100 protein positive cells, because the total number of S-100 protein positive cells was greater than that of OKT-6 positive cells. The existence of a larger number of OKT-6 positive cells in the inguinal lymph nodes than in the cervical lymph nodes may be because there are more opportunities for the lower extremities to receive different kinds of stimuli than for the head. LCs may receive some stimulation from the external environment and/or retain antigens. LCs might also be responsible for T cell dependent immune responses. Our results suggest that LCs and IDCs have slightly different immunological characteristics, and therefore, they may have some different functions.

The nature of Hodgkin and Reed-Sternberg cells, their association with EBV, and their relationship to anaplastic large-cell lymphoma.

This review focuses on the cellular origin of Hodgkin and Reed-Sternberg (HRS) cells, their association with the Epstein-Barr virus (EBV), and their relation to Ki-1+ anaplastic large-cell (ALC) lymphoma. The tingibility of HRS cells in paraffin sections for polyclonal immunoglobulin represents a staining artifact and thus can no longer serve as an argument for the histiocytic nature of HRS cells. Immunolabeling studies do not support the putative relationship of HRS cells to cell types such as macrophages or interdigitating reticulum cells, but instead suggest: a) that lymphocyte-predominant (LP) Hodgkin's disease (HD) represents a B-cell neoplasm which is distinct from non-LP HD, and b) that non-LP HD constitutes a syndrome rather than a disease entity, with the existence of T-cell types and B-cell types. HRS cells (and the tumor cells in ALC lymphomas) frequently display an immature genotype in association with late activation markers, leading to the assumption that the tumor cells in many cases of HD (and some cases of ALC lymphoma) may be derived from immature lymphoid cells that are infected by a virus that superimposes characteristics of mature activated lymphocytes on these cells. Southern blotting, in situ hybridization, and polymerase chain reaction (PCR) experiments revealed an association of EBV with HRS cells in a significant proportion of HD cases, suggesting that EBV may be responsible for the dissociation between genotype and phenotype in HRS cells, because EBV is a strong inducer of the activation antigens CD30 and CDw70.(ABSTRACT TRUNCATED AT 250 WORDS)

Interdigitating Reticulum Cell Sarcoma Positive immunohistochemistry for HLA-DR and two other activation antigens, CD30(Ki-1) and CD25(IL2R).

This communication reports a case of the rare interdigitating reticulum cell (IDRC) sarcoma of lymph nodes in a 46-year-old man. Extensive immunophenotypic analysis on paraffin and frozen sections revealed positivity on the neoplastic cells for protein S-100 as well as for antigens CD1, HLA-DR, CD4, CD25 (IL2R) and CD30 (Ki-1). The simultaneous positivity for the three activation antigens CD30, HLA-DR, and IL2R, a phenomenon mostly described in H and S-R cells of Hodgkin's disease, is discussed in particular.

Interdigitating Reticulum Cell Sarcoma with Unusual Features

A case of interdigitating reticulum cell sarcoma is reported in a cervical lymph node of a 67-year-old man who had a previously diagnosed nodular lymphocytic lymphoma in the same anatomic location. Ultrastructurally, the neoplastic cells contained cylindrical confronting cisternae, and associated benign lymphocytes had tubuloreticular structures in their cytoplasm. The patient was treated with combination chemotherapy-radiation therapy and is alive and well with no evidence of disease approximately 2 years after completing therapy. The clinical and pathologic features of previously reported cases of interdigitating reticulum cell sarcomas are compared to those of the reported case.