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E C Butcher

Publications and source records attributed to E C Butcher.

At least 181 records · Page 10Linked to original sources
PubMed1988

Ly-6C is a monocyte/macrophage and endothelial cell differentiation antigen regulated by interferon-gamma.

Using a new Ly-6C-specific antibody (Monts-1) we show that this class of antigens are differentially expressed on monocytes/macrophages and endothelial cells. Recently elicited peritoneal exudate Mac-1+ mononuclear cells, as well as Mac-1+ mononuclear cells in the bone marrow and in the peripheral blood, express high levels of Ly-6C. Ly-6C+ mononuclear Mac-1+ cells are absent in normal uninflamed skin, but are present in high numbers in skin lesions 3 days after the s.c. injection of lipopolysaccharide, concanavalin A or complete Freund's adjuvant. In addition, large Ly-6C+ mononuclear cells are predominant in chronic granulomas induced by complete Freund's adjuvant. Resident macrophages in a variety of tissues express low levels or in many cases do not express Ly-6C. Two out of three monocyte-like cell lines are Ly-6C+, whereas macrophage-like cell lines are negative. Ly-6C+ monocytes/macrophages lose the Ly-6C antigen within 24 h after in vitro culture. Ly-6C- cultured monocytes and Ly-6C- monocyte-like cell lines, but not fully differentiated macrophages and macrophage-like cell lines, can be induced to express the Ly-6C antigen by interferon-gamma. A population of small vessel endothelial cells in diverse tissues also express high levels of Ly-6C. The present findings suggest that the Ly-6C antigen family, shown by others to be involved in T cell activation, may have more general importance in immune responses and cellular differentiation than previously appreciated.

Animals↗
PubMed1988

Memory B cells express a phenotype consistent with migratory competence after secondary but not short-term primary immunization.

The cell surface phenotype of dinitrophenol (DNP)-specific memory B cells, defined by their capacity to transfer IgG responses into syngeneic irradiated recipients, was assessed using two markers of relevance to lymphocyte migratory properties: (i) peanut agglutinin, which binds to terminal galactosyl residues expressed at high levels by several nonmigrating lymphocyte subsets and, among lymph node B cells, is highly specific for germinal center cells; and (ii) MEL-14, a monoclonal antibody specific for lymphocyte surface receptors required for migration from the blood into peripheral lymph nodes. At various times after primary or secondary immunization with DNP-keyhole limpet hemocyananin (KLH), lymph node B cells were separated by fluorescence-activated cell sorting on the basis of staining with PNA and/or MEL-14, and the presence of B-memory cells in each fraction was assessed by adoptive transfer with antigen (DNP-KLH) and helper T cells. One week after immunization, most of the memory sorted in the PNAhi population, confirming a previous report by R. F. Coico, B. S. Bhogal, and G. J. Thorbecke (J. Immunol. 131, 2254, 1983) that early memory B cells or their precursors are contained within the germinal center cell population, a population which is known to be MEL-14- and migratory-incompetent. Six weeks after primary stimulation, however, the bulk of memory cells, unlike germinal center cells, were MEL-14hi. After secondary immunization, memory was still predominantly MEL-14+ and PNAlo, although in some experiments adoptive responses were transferred by all sorted fractions. The results are consistent with the hypothesis that antigen-specific B cells initially undergo local (sessile) differentiation and proliferation in germinal centers, where they develop the capacity for adoptive transfer of antigen-specific secondary responses, but that with continued development their long-lived memory-containing progeny express a phenotype permitting their reentry into the recirculating lymphocyte pool.

Animals↗
PubMed1988

Selective recognition of mucosal lymphoid high endothelium by gut intraepithelial leukocytes.

Circulating precursors of mucosal immunoglobulin A plasma cells and T-cell immunoblasts migrate selectively into mucosal sites from the blood, but the mechanisms controlling this selective trafficking have not been determined. One possibility is that the site-specific extravasation of circulating effector cell populations is determined by organ-specific endothelial cell recognition mechanisms. Here we have assessed the ability of isolated mouse gut intraepithelial lymphocytes to recognize and bind to mucosal versus nonmucosal lymphoid organ high endothelial venules, vessels that support high levels of lymphocyte traffic in vivo. In an in vitro assay of lymphocyte interaction with high endothelial venules in frozen sections, intraepithelial leukocytes bind well to high endothelial venules in Peyer's patches but, unlike most circulating B and T lymphocytes, are unable to interact with peripheral lymph node high endothelial venules. Furthermore, we show by in situ immunohistology and in cell suspension immunofluorescence studies that intraepithelial leukocytes fail to stain with a monoclonal antibody, MEL-14, against putative lymphocyte receptors for lymph node high endothelial venules. Thus, they lack a cell surface glycoprotein required for homing to peripheral nodes. The demonstration of organ-specific recognition of endothelial cells by a normal mucosal effector lymphocyte population suggests that selective interactions with endothelium may play an important role in controlling the distribution of effector cells in vivo. The utilization of organ-specific endothelial cell recognition mechanisms by circulating precursors of mucosal effector cells could explain both the unification of immune responses in diverse mucosal sites and the physiologic segregation of mucosal from nonmucosal immune mechanisms.

Animals↗
PubMed1988

Homing receptors and metastasis.

As discussed in the preceding sections, there are several indications that the lymphocyte homing receptors involved in the normal process of lymphocyte recirculation are also relevant to the behavior of metastatic cells. Cell fusion experiments indicate that previously nonmetastatic cells can acquire metastatic capacity from fusion with normal lymphocytes. Murine T lymphomas that bear high levels of functional homing receptors can metastasize to peripheral lymphoid organs, whereas those lymphomas lacking homing receptors cannot. Virtually all lymph node metastases of lymphomas contain a high proportion of MEL-14hi cells, even if the primary tumor has been selected to be relatively deficient in these cells. Further investigations of the biology of lymphocyte homing receptors will reveal whether or not there are additional lymphocyte homing receptors and will clarify the role of lymphocyte homing receptors in metastasis. Antibodies against three lymphocyte homing receptors could therefore be useful for diagnosis and treatment of metastatic disease.

Animals↗
PubMed1988

Evolutionary conservation of tissue-specific lymphocyte-endothelial cell recognition mechanisms involved in lymphocyte homing.

Tissue-specific interactions with specialized high endothelial venules (HEV) direct the homing of lymphocytes from the blood into peripheral lymph nodes, mucosal lymphoid organs, and tissue sites of chronic inflammation. These interactions have been demonstrated in all mammalian species examined and thus appear highly conserved. To assess the degree of evolutionary divergence in lymphocyte-HEV recognition mechanisms, we have studied the ability of lymphocytes to interact with HEV across species barriers. By using an in vitro assay of lymphocyte binding to HEV in frozen sections of lymphoid tissues, we confirm that mouse, guinea pig, and human lymphocytes bind to xenogeneic as well as homologous HEV. In addition, we show that mouse and human lymphoid cell lines that bind selectively to either peripheral lymph node or mucosal vessels (Peyer's patches, appendix) in homologous lymphoid tissues exhibit the same organ specificity in binding to xenogeneic HEV. Furthermore, monoclonal antibodies that recognize lymphocyte "homing receptors" and block homologous lymphocyte binding to peripheral lymph node or to mucosal HEV, also inhibit lymphocyte interactions with xenogeneic HEV in a tissue-specific fashion. Similarly, anti-HEV antibodies against organ-specific mouse high endothelial cell "addressins" involved in lymphocyte homing to peripheral lymph node or mucosal lymphoid organs, not only block the adhesion of mouse lymphocytes but also of human lymphocytes to target mouse HEV. The results illustrate a remarkable degree of functional conservation of elements mediating these cell-cell recognition events involved in organ-specific lymphocyte homing.

Animals↗
PubMed1988

Immunohistologic and functional characterization of a vascular addressin involved in lymphocyte homing into peripheral lymph nodes.

The tissue localization or "homing" of circulating lymphocytes is directed in part by specialized vessels that define sites of lymphocyte exit from the blood. In peripheral lymph nodes, mucosal lymphoid tissues (Peyer's patches and appendix), and sites of chronic inflammation, for example, lymphocytes leave the blood by adhering to and migrating between those endothelial cells lining postcapillary high endothelial venules (HEV). Functional analyses of lymphocyte interactions with HEV have shown the lymphocytes can discriminate between HEV in different tissues, indicating that HEV express tissue-specific determinants or address signals for lymphocyte recognition. We recently described such a tissue-specific "vascular addressin" that is selectively expressed by endothelial cells supporting lymphocyte extravasation into mucosal tissues and that appears to be required for mucosa-specific lymphocyte homing (Streeter, P. R., E. L. Berg, B. N. Rouse, R. F. Bargatze, and E. C. Butcher. 1988. Nature (Lond.). 331:41-46). Here we document the existence and tissue-specific distribution of a distinct HEV differentiation antigen. Defined by monoclonal antibody MECA-79, this antigen is expressed at high levels on the lumenal surface and in the cytoplasm of HEV in peripheral lymph nodes. By contrast, although MECA-79 stains many HEV in the mucosal Peyer's patches, expression in most cases is restricted to the perivascular or ablumenal aspect of these venules. In the small intestine lamina propria, a mucosa-associated site that supports the extravasation of lymphocytes, venules do not stain with MECA-79. Finally, we demonstrate that MECA-79 blocks binding of both normal lymphocytes and a peripheral lymph node-specific lymphoma to peripheral lymph node HEV in vitro and that it also inhibits normal lymphocyte homing to peripheral lymph nodes in vivo without significantly influencing lymphocyte interactions with Peyer's patch HEV in vitro or in vivo. Thus, MECA-79 defines a novel vascular addressin involved in directing lymphocyte homing to peripheral lymph nodes.

Animals↗
PubMed1988

Recombinant gamma interferon increases the binding of peripheral blood mononuclear leukocytes and a Leu-3+ T lymphocyte clone to cultured keratinocytes and to a malignant cutaneous squamous carcinoma cell line that is blocked by antibody against the LFA-1 molecule.

Because keratinocytes (KCs) express HLA-DR in a wide variety of skin diseases in which mononuclear leukocytes are observed in close apposition to KCs (i.e., graft-versus-host disease), and since gamma interferon (IFN-gamma) induces HLA-DR expression on KCs, we asked whether IFN-gamma treatment of KCs would influence the adherence of mononuclear leukocytes. When allogeneic peripheral blood mononuclear leukocytes (PBML) and a Leu-3+ T cell clone were coincubated with IFN-gamma-treated KCs (300 U/ml, 3 days), there was a marked increase in binding compared with nontreated KCs. Similar binding results were obtained using a cutaneous squamous carcinoma cell line (SCL-1) after IFN-gamma treatment. The IFN effect was relatively specific for IFN-gamma, as neither IFN-alpha nor -beta had any effect. Tumor necrosis factor exposure (500 U/ml, 3 days) increased the binding of the Leu-3+ T cell clone to both KCs and SCL-1 cells. Neutrophils displayed a less marked (but statistically significant) increase in binding to IFN-gamma-treated KCs. Using the Leu-3+ cell clone and SCL-1 cells, detailed kinetic analysis of the effect of IFN-gamma on binding was performed. The increased adherence between the cells began to appear after only 7 hours of treatment with r-IFN-gamma (300 U/ml) and reached a plateau at 48 hours, with significantly enhanced binding continuing for at least 48 hours after removal of IFN-gamma. The mechanism of binding was explored by preincubation of the PBML/Leu-3+ T cells with anti-LFA-1 (lymphocyte function-associated antigen) antibody (0.6-6.0 micrograms/ml), which totally inhibited the binding with no effect by anti-LFA-2 or -3 or class I or II antibodies despite documented binding of these antibodies to the cells. These results suggest that, after exposure to IFN-gamma, the ability of KCs to bind mononuclear leukocytes is strongly enhanced, and this adherence may be important in leukocyte trafficking in the skin as well as contributing to altered KC-leukocyte interaction, which may be of fundamental importance in a variety of skin disease.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1988

Expression of lymphocyte homing receptor antigen in non-Hodgkin's lymphoma.

In man, lymphocyte binding to high endothelial venules (HEVs) involves specific 85-95 kd cell surface glycoprotein(s) recognized by the monoclonal antibodies Hermes-1 and Hermes-3. These putative "homing receptor" molecule(s) are believed to play an important role in the normal regulation of lymphocyte circulation. To investigate the possibility that homing receptors also play a role in the biology of lymphoid malignancies, the authors studied over 300 cases of non-Hodgkin's lymphoma by immunohistologic staining with Hermes-1 and -3, antibodies that define two distinct epitopes on the gp 85-95 putative homing receptor molecules. Furthermore, they directly compared expression of the Hermes-3 antigen with clinical extent of disease in 57 patients with diffuse large cell lymphoma. They found that staining of the various subtypes of lymphoma was heterogeneous, and in general correlated with patterns of expression seen in benign lymphoid populations. Essentially all normal lymphoid populations examined, except germinal center B cells and most cortical thymocytes, bear a high level of homing receptor antigen. Similarly, nearly all peripheral T-cell lymphomas, diffuse small cell lymphomas of B lineage, and plasma cell tumors were positive for homing receptor antigen (95%, 97%, and 100%, respectively). Small noncleaved cell, follicular, and diffuse large cell lymphomas of B lineage, tumors having morphologic or immunologic features resembling germinal center cells, frequently failed to express Hermes-defined epitopes (81%, 41%, 25% Hermes-3-, respectively). Antigen expression in T-lymphoblastic lymphomas strongly correlated with immunophenotypic subtypes: only 8% of CD4+/CD8+ were Hermes-1+ versus 86% of CD4-/CD8- and 43% of CD4+/CD8-. Hermes-3 expression by cases of diffuse, large cell lymphoma which showed generalized lymph node involvement (a pattern strongly suggestive of HEV-mediated spread; 100% Hermes-3+, mean intensity 3.4) was higher than that of cases with localized or multifocal, contiguous involvement (consistent with lymphatic spread; 69% Hermes-3+, mean intensity 2.2), but these differences did not achieve statistical significance. The results indicate that homing receptor antigen expression, although perhaps necessary for wide-spread blood-borne lymphoma dissemination to lymphoid sites, is not in and of itself sufficient to predict such behavior in this subtype of lymphoid malignancy.

Antibodies, Monoclonal↗
PubMed1988

High endothelial differentiation in human lymphoid and inflammatory tissues defined by monoclonal antibody HECA-452.

Lymphocyte traffic into lymph nodes and into mucosa-associated lymphoid tissues is regulated by specialized postcapillary high endothelial venules (HEVs). The authors have produced a rat monoclonal antibody, HECA-452, that detects a human endothelial cell differentiation antigen selectively expressed on high endothelium. In immunoperoxidase studies, HECA-452 intensely stains all HEVs within lymphoid organs. In normal nonlymphoid tissues the antibody stains no vascular endothelium. The antibody, in addition to reacting with high endothelium, cross-reacts with a set of monocytic cells. In pathologic states such as autoimmune thyroiditis and Crohn's disease, known for the development of dense, frequently organized, lymphocytic infiltrates, HECA-452 detects HEV-like vessels containing luminal and intramural lymphocytes, presumably in the process of extravasating. The antigen was not expressed at detectable levels by venules in less heavily infiltrated chronic inflammatory sites nor in acutely inflamed tissues. In lymphoid malignancies, the only vessels stained were morphologically characteristic HEVs in association with areas of residual normal lymphoid tissue or reactive lymphocytic infiltrates. The specificity of HECA-452 for high endothelial cells confirms the highly specialized nature of these vessels and will permit studies of the regulation of high endothelial cell differentiation in vivo and in vitro. The HECA-452 antigen is preserved in paraffin sections of sublimate formaldehyde- and also routinely formalin-fixed tissues. Thus, HECA-452 will be widely applicable for the immunohistologic detection of endothelium specialized for the support of highly increased lymphocyte extravasation in inflammatory sites.

Animals↗
PubMed1987

High endothelial venule binding as a predictor of the dissemination of passaged murine lymphomas.

It has long been postulated that normal lymphocyte homing mechanisms help determine the metastatic spread of lymphoid neoplasms. The traffic of normal lymphocytes is controlled in part by the regulated expression of surface receptors for high endothelial venules (HEV), specialized venules that mediate the extravasation of circulating lymphocytes from the blood into lymphoid organs and sites of chronic inflammation. Here we have compared the in vivo growth patterns of HEV-binding vs. nonbinding murine lymphomas passaged intramuscularly into syngeneic recipients. We report that lymphomas that bind well to HEV (as assessed in a quantitative in vitro assay) disseminate widely via the blood, involving all lymph node groups symmetrically. Although both HEV-binding and nonbinding lymphomas gain access to the blood, gross involvement of lymph nodes by nonbinding lymphomas is limited to nodes draining local tumor at the site of injection, a prominent feature of these lymphomas; distant lymph nodes are not enlarged. The results suggest that the expression of functional receptors for HEV either controls the hematogenous dissemination of malignant lymphocyte populations to HEV-bearing organs, or is coregulated with factors determining this metastatic behavior. The findings support the concept that normal lymphocyte homing mechanisms are important to the spread of leukemias and lymphomas.

Animals↗
PubMed1987

Leukocyte-endothelial cell recognition: evidence of a common molecular mechanism shared by neutrophils, lymphocytes, and other leukocytes.

The interaction of leukocytes with endothelial cells is intrinsic to the process of leukocyte extravasation, whether during the entry of blood polymorphonuclear leukocytes and monocytes into sites of acute and chronic inflammation, or during the homing of lymphocytes to lymphoid organs. A lymphocyte surface glycoprotein, defined by monoclonal antibody MEL-14, has been described that appears to mediate lymphocyte recognition of postcapillary venules in peripheral lymph nodes, and to control the migration of lymphocytes from the blood into these lymphoid organs. We now report that the antigenic determinant recognized by MEL-14 is present at high levels on other leukocytes as well, including neutrophils, monocytes, and eosinophils; and we demonstrate involvement of the MEL-14 antigen in neutrophil-endothelial cell interactions. MEL-14 immunoprecipitates a neutrophil surface protein of Mr approximately 100,000, similar in m.w. to the 80,000 to 90,000 dalton lymphocyte surface MEL-14 antigen, and it blocks the interaction of neutrophils with endothelial cells in an in vitro model of adhesion to postcapillary venules in lymph node frozen sections. Neutrophil binding to lymph node venules is also inhibited by PPME, a mannose-6-phosphate-rich yeast polysaccharide that is thought to mimic the endothelial cell ligand for the MEL-14-defined lymphocyte receptor. Interestingly, neither MEL-14 nor PPME exhibit a major effect on neutrophil binding to postcapillary venules in Peyer's patches, suggesting that as for lymphocytes, the neutrophil MEL-14 antigen is involved in recognition of tissue-specific endothelial determinants. Finally, we show that MEL-14 inhibits the capacity of neutrophils to migrate from the blood into sites of acute inflammation in the skin. These observations lead us to propose that receptors for tissue-specific endothelial determinants are utilized by neutrophils and lymphocytes and probably other leukocytes during the physiologic process of leukocyte extravasation in vivo.

Animals↗
PubMed1987

Lymphoid tissue- and inflammation-specific endothelial cell differentiation defined by monoclonal antibodies.

Endothelial cells play an essential role in immune responses by regulating the entry of leukocytes into lymphoid tissues and sites of inflammation. As an initial approach to analyzing endothelial cell specialization in relation to such immune function, we have produced monoclonal antibodies (MAB) against mouse lymph node endothelium. Three antibodies were selected: MECA-20, recognizing the endothelium of all blood vessels in lymphoid as well as non-lymphoid organs; MECA-217, which stains the endothelium lining large elastic arteries, but among small vessels is specific for post-capillary venules within lymphoid organs and tissues exposed to exogenous antigen, such as skin and uterus; and MECA-325, an antibody that demonstrates specificity for the specialized high endothelial venules (HEV) that control lymphocyte homing into lymph nodes and Peyer's patches. MECA-325 failed to stain vessels in any non-lymphoid organs tested. Immunoperoxidase studies of HEV in lymph node frozen sections, and of isolated high endothelial cells in suspensions, demonstrated that the antigens recognized by all three antibodies are expressed at the cell surface; those defined by MECA-20 and MECA-325 are also present in the cytoplasm. To study the regulation of the antigens defined by these MAB in relation to extra-lymphoid immune reactions, we assessed their expression in induced s.c. granulomas as a model for chronic inflammation. Small vessels in the granulomas were already stained by MECA-217 in the first days of development. In contrast MECA-325 detected postcapillary venules (which frequently displayed the morphologic characteristics of HEV) only from approximately 1 wk, in parallel with the development of a persistent mononuclear cell infiltrate including numerous lymphocytes. The selective appearance of the MECA-325 antigen on vascular endothelium supporting lymphocyte traffic in both lymphoid and extra-lymphoid sites suggests that this antigen may play an important role in the process of lymphocyte extravasation. The demonstration of lymphoid organ- and inflammation-specific microvascular antigens offers direct evidence for a complex specialization of endothelium in relation to immune stimuli, and supports the concept that microvascular differentiation may play an important role in local immune responses.

Animals↗
PubMed1987

The correlation of lectin-stimulated proliferation and cytotoxicity in murine thymocytes with expression of the MEL-14-defined homing receptor.

The relationship between the expression of the MEL-14-defined lymphocyte homing receptor and the proliferation and functional differentiation of thymocytes in response to lectin stimulation was examined. Two-color fluorescent staining with MEL-14 in various combinations with PNA and anti-Ly-2 and anti-L3T4 was used to separate thymocyte populations for functional analysis. A high cloning-efficiency limit-dilution culture system was used to determine the frequency of all cells responsive to concanavalin A (PTL-p) or of all precursors of lectin-enhanced cytolytic lymphocytes (CTL-p). As expected from earlier studies, PTL-p and CTL-p were concentrated in the PNA- thymocytes, PTL-p were in both the Ly-2- L3T4+ and the Ly-2+ L3T4- subpopulations, and CTL-p were predominantely in the Ly-2+ L3T4- subpopulation. Within the PNA- thymocytes, two distinct peaks of PTL-p were found in cells stained with MEL-14, corresponding to MEL-14- and MEL-14medium-to-high cells, whereas the CTL-p frequency increased in fractions showing increasing expression of the MEL-14-defined antigen. Within the Ly-2- L3T4+ subpopulation, two distinct peaks of PTL-p were found corresponding to groups of MEL-14- and MEL-14medium-to-high cells, with the intermediate fraction of MEL-14low cells displaying a very low PTL-p frequency. The Ly-2+ L3T4- subpopulation included fewer MEL-14- cells and more MEL-14high cells than the Ly-2- L3T4+ subpopulation. Within the Ly-2+ L3T4- subpopulation, the few MEL-14- cells expressed a relatively low but definite frequency of CTL-p and PTL-p. The more numerous MEL-14+, Ly-2+ L3T4- cells included a high frequency of CTL-p and PTL-p, which did not vary over the medium-to-high MEL-14 expression range. These results indicate that the correlation of MEL-14 expression with CTL-p frequency among thymocytes is largely a consequence of the relative frequency of Ly-2+ L3T4- cells in the separated fractions, rather than a direct link between MEL-14 expression and function. Nevertheless, MEL-14 does define significant heterogeneity in both the Ly-2+ L3T4- and the Ly-2- L3T4+ subpopulations. In particular, there is a reduced functional response among the small subgroup of Ly-2+ L3T4- MEL-14- cells, suggesting this population includes either immature cells or cells of a different functional type.

Animals↗
PubMed1987

Receptors involved in lymphocyte homing: relationship between a carbohydrate-binding receptor and the MEL-14 antigen.

Blood-borne lymphocytes extravasate in large numbers within peripheral lymph nodes (PN) and other secondary lymphoid organs. It has been proposed that the initiation of extravasation is based upon a family of cell adhesion molecules (homing receptors) that mediate lymphocyte attachment to specialized high endothelial venules (HEV) within the lymphoid tissues. A putative homing receptor has been identified by the monoclonal antibody, MEL-14, which recognizes an 80-90-kD glycoprotein on the surface of mouse lymphocytes and blocks the attachment of lymphocytes to PN HEV. In a companion study we characterize a carbohydrate-binding receptor on the surface of mouse lymphocytes that also appears to be involved in the interaction of lymphocytes with PN HEV. This receptor selectively binds to fluorescent beads derivatized with PPME, a polysaccharide rich in mannose-6-phosphate. In this report we examine the relationship between this carbohydrate-binding receptor and the putative homing receptor identified by the MEL-14 antibody. We found that: MEL-14 completely and selectively blocks the activity of the carbohydrate-binding receptor on mouse lymphocytes; the ability of six lymphoma cell lines to bind PPME beads correlates with cell-surface expression of the MEL-14 antigen, as well as PN HEV-binding activity; selection of lymphoma cell line variants for PPME-bead binding by fluorescence-activated cell sorting (FACS) produces highly correlated (r = 0.974, P less than 0.001) and selective changes in MEL-14 antigen expression. These results show that the carbohydrate-binding receptor on lymphocytes and the MEL-14 antigen, which have been independently implicated as receptors involved in PN-specific HEV attachment, are very closely related, if not identical, molecules.

Animals↗