The Human la System

Terminal deoxynucleotidyl transferase and HLA-DR expression appear unrelated to prognosis of acute myeloid leukaemia

Mononuclear cells from peripheral blood or bone marrow from 314 patients with acute myeloid leukaemia were examined for the presence of nuclear terminal deoxynucleotidyl transferase (304 patients), surface membrane expression of HLA-DR (314 patients) and the common acute lymphoblastic leukaemia antigen (281 patients). All patients were treated with identical remission induction chemotherapy, and morphological diagnosis was carried out in a central laboratory. The overall complete remission rate was 70%. There were no significant correlations between the immunological markers and complete remission rate, duration of remission, or survival.

Anti-Ia antibody diminishes ocular inflammation in experimental autoimmune uveitis

An experimental model of inflammatory eye disease, experimental autoimmune uveitis (EAU), was established by injecting rats in the footpad with S-antigen in complete Freund's adjuvant. This model system was used to evaluate the role of major histocompatibility complex (MHC) class II antigens (Ia) in the pathogenesis of this T cell mediated disease. One day prior to S-antigen priming, rats were injected with either anti-Ia antibodies or with mouse ascites. Clinical and histopathological analysis of eyes from rats treated with anti-Ia antibody showed less ocular inflammation as well as a delay in onset of EAU when compared to controls (p = 0.01). Furthermore, immunocytochemical evaluation demonstrated that tissue obtained from animals receiving anti-Ia therapy also expressed less Ia antigen, as well as a diminution in the number of infiltrating macrophages and lymphocytes. These data show that anti-Ia treatment significantly modifies the course of EAU in the rat. In addition, this study suggests that MHC class II antigen expression may be involved in the initiation and continuation of immune responses that results in ocular inflammatory diseases.

OKT4+ T cell abnormality in patients with active systemic lupus erythematosus: HLA-DR antigen expressions

The objective of this study was to define immunologic T cell abnormality characteristic of active systemic lupus erythematosus (SLE). Eight of nine patients who had severe clinical and laboratory manifestations of active SLE had a characteristically marked increase in OKT4+ and a decrease in OKT8+ T cells. Using OKIa1 and OKDR monoclonal antibody, we found that, in circulating blood of all patients with active SLE, an increased percentage of Ia+ and DR+ T cells is present compared to inactive SLE. Five of these active SLE patients had Tac+ antigens, an interleukin 2 receptor on OKT4+ and OKT8+ T cell subsets in resting blood. The present study demonstrates that Ia+ and DR+ antigens are selectively expressed on the majority of OKT4+ T cell subsets of all patients with active SLE, whereas Ia+ and DR+ antigens are expressed almost equally on both OKT4+ and OKT8+ T cell subsets in inactive SLE. The elevated percentage of Ia+, DR+, OKT4+ T cells in active SLE was accompanied by a highly depressed proliferative response to T cell mitogens, phytohemagglutinin and concanavalin A. However, OKT8+ T cell subsets in active SLE possessed a normal proliferative response to these T cell mitogens. We conclude that this abnormality of activated OKT4+ T cells bearing HLA-DR antigens may play a role in the development of active SLE.

T cell proliferation induced by anti-CD3 antibodies: requirement for a T-T cell interaction

In the presence of interleukin 2 (IL2), soluble anti-CD3 monoclonal antibodies can stimulate highly purified normal T lymphocytes to proliferate. In these experiments HLADR+ T cells constituted 13 to 20% of the total cell population, and other HLADR+ cells, such as monocytes and B lymphocytes, constituted less than 1% of the population. When the HLADR+ T cells were removed from the total T cell population by cytofluorometric sorting, the residual HLADR- T cells failed to respond to soluble anti-CD3 plus IL2. When the separated HLADR+ T cells were recombined with the HLADR- T cells, a response was again found. This response was dependent on the dose of HLADR+ T cells added in the mixture. Irradiation individually of the HLADR+ and DR- T cells revealed that the proliferation in the cell mixture was predominantly, if not exclusively, by the HLADR- T cells. The ability of the HLADR+ T cells to provide a signal necessary to this proliferation was radioresistant. These data indicate that under the conditions of these experiments HLADR+ ("activated") T cells provide a signal necessary to the responsiveness of previously resting T cells.

Enhancement of surface antigen expression on human breast carcinoma cells by recombinant human interferons

Eight different human breast carcinoma cell lines, as well as clonally derived cell lines, were used to study the expression of four different monoclonal antibody (MAb)-defined tumor-associated antigens (TAAs) and the ability of recombinant human (rHu)-interferon (IFN)-alpha A and rHu-IFN-gamma to increase tumor-associated and/or normal cell-surface antigen expression. The different breast tumor cell lines expressed a wide range of antigenic phenotypes with respect to four different cell-surface TAAs. The cell lines could be divided into high and low antigen-expressing groups based on their constitutive levels of the four TAAs. In general, those breast tumor cell lines that expressed high levels of carcinoembryonic antigen, the MAb DF-3-defined 290-kD antigen, and the 90-kD antigen reactive with MAb B6.2 were poor candidates for antigen augmentation by rHu-IFN-alpha A or rHu-IFN-gamma. In contrast, breast cell lines that constitutively express low levels of these TAAs were found to be highly responsive to the ability of either of the rHu-IFNs to enhance MAb binding to the cell surface. Treatment with either of the rHu-IFNs increased the level of surface binding of MAbs as much as fourfold. The relative abilities of the IFNs to increase MAb binding to the surface of human breast tumor cells thus appeared to depend on the degree of constitutive surface antigen expression of the breast tumor cells. The high-molecular-weight TAA, TAG-72, is known not to be expressed on most cell lines but is expressed on the majority of human carcinoma biopsies. Most breast tumor cell lines employed in this study did not express the TAG-72 high-molecular-weight TAA. However, rHu-IFN-alpha A did substantially increase the level of expression of TAG-72 on the surface of breast tumor cells that were isolated from a pleural effusion. These studies may thus provide an important insight into the criteria used in the selection of carcinoma patients for IFN-mediated antigen augmentation when employing MAb-guided radioimmunolocalization or MAb-guided therapy.

HLA-DR antigens in normal, inflammatory, and neoplastic salivary glands

A monoclonal antibody to HLA-DR antigens that is reactive in formalin-fixed tissues was used with the immunoperoxidase method to evaluate 212 salivary gland lesions (normal, nonspecific, and autoimmune inflammatory, benign, and malignant tumors). Results of immunostaining showed that (1) intercalated ducts, myoepithelial cells, and acinous cells of normal salivary glands express HLA-DR antigens, (2) autoimmune salivary gland disease results in greater HLA-DR expression than that seen in nonspecific inflammatory lesions or normal glands, (3) stromal cells associated with benign and malignant salivary gland tumors express HLA-DR antigens, and (4) numerous benign and malignant salivary gland tumors express HLA-DR antigens. It was of interest that lymphocyte-rich Warthin's tumors displayed epithelial immunoreactivity, whereas oncocytomas devoid of a lymphocytic component were invariably negative. This suggests a lymphocyte-mediated role in salivary epithelial HLA-DR expression. It appears that HLA-DR expression is both a normal and an inducible phenomenon in salivary glands, salivary gland neoplasia, and the desmoplastic host response. There is no discriminatory role in the immunologic detection of HLA-DR for differential diagnosis of salivary gland tumors.

Protection from autoimmune disease as the third function of the major histocompatibility gene complex

The collection of genes known as the major histocompatibility gene complex (MHC) appears to subserve three functions. Firstly, its class I genes, coding for antigens on all nucleated cells, assist clones of cytotoxic T cells to kill virus-infected cells quickly, without being muffled by the myriad numbers of free virus particles. Secondly, the absence of autoimmunity to both class I and class II MHC antigens shows that they impose unbreakable tolerances on the immune repertoire. The class II antigens, which are confined to B lymphocytes (if their apparent occurrence on other dividing cells is a cross-reaction), may have the sole function of tolerance induction, supplementing this activity of the class I antigens. Both sets of MHC antigens serve to diversify immunity-repertoire gaps among individuals of a population, thus hampering epidemic spread of infection and providing a diversity of immunoreactivity that favours survival of at least some members of a population in the face of pestilence. Thirdly, the permanence of the MHC tolerance inductions affords a powerful, adaptable mechanism for curtailment of reproductively disadvantageous autoimmune disease liable to arise through somatic mutations in lymphocytes multiplying under drive from a microbial antigenic stimulus.

Immunohistochemical analysis of experimental autoimmune uveoretinitis (EAU) induced by interphotoreceptor retinoid-binding protein (IRBP) in the rat

Experimental autoimmune uveoretinitis (EAU) was induced in rats by immunization with bovine interphotoreceptor retinoid-binding protein (IRBP) and studied by immunohistochemistry. In general, the IRBP induction of inflammatory cellular components and expression of immune-related antigens on various non-lymphoid cells resembled those provoked by S-antigen (S-Ag). However, differences were found between the two diseases, including: 1) The increase in T suppressor/cytotoxic cells occurred in IRBP EAU more rapidly than in S-Ag EAU. 2) Fewer numbers of non-lymphoid cells expressed major histocompatibility complex class II surface antigens in IRBP EAU than in S-Ag EAU. The immunopathogenic mechanism of EAU induced by these two retinal antigens are discussed.

CD4+ T cell activation in multiple sclerosis

Interleukin-2 (IL-2) production by CD4-enriched T cells from multiple sclerosis (MS) patients and normal individuals stimulated with concanavalin A (conA) and/or autologous and allogeneic B lymphoid cell lines (B-LCL) was evaluated 24, 48 and 96 h after stimulation. ConA-stimulated CD4+ cells from MS patients did not produce significantly more IL-2 than normal CD4+ cells. In contrast, autologous B-LCL-induced IL-2 production by MS CD4+ cells significantly (P = 0.026) exceeded that produced by normal CD4+ cells identically stimulated after 24 h in culture. Differences in IL-2 production by CD4+ cells from MS patients reached highest significance using allogeneic B-LCL, whose stimulatory capacity was similar, whether established from normal individuals or MS patients. This increased IL-2 production in response to B-LCL may represent a supranormal response of CD4+ cells from MS patients to class II major histocompatibility (MHC)-associated stimuli. It suggests that the deficiency of suppressor T cell functions postulated to play a role in MS does not arise from a lack of IL-2 induction and might indicate that bursts of IL-2 production could play a role in MS.

Poliovirus infection of established human blood cell lines: relationship between the differentiation stage and susceptibility of cell killing

The replication of type 1 poliovirus in 13 established human blood cell lines differing in the differentiation stage and cell lineage was investigated. Three T (CCRF-CEM, CCRF-HSB-2, and Molt-3) and three B (Raji, CCRF-SB, and RPMI 8226) cell lines showed no cytopathic effects (CPE) or virus production. CPE associated with virus production were detected in the other seven cell lines: HL-60, ML-1, and KG-1 (granulocytic lineage), U-937 and THP-1 (monocytic lineage), K-562 (erythroid lineage), and Molt-4 (T cell lineage). These susceptible cell lines greatly differed in the speed at which the CPE progressed. The progression of CPE was faster in relatively well-differentiated cell lines such as HL-60 and U-937, independently of the multiplicity of infection, than in less differentiated cell lines such as K-562, KG-1, and THP-1. Thus, for the same lineage, the speed at which CPE progressed became proportionally higher with subsequent differentiation stages. In the K-562 cell culture, CPE were not observed until at least 5 days postinfection (p.i.), while more than 80% of HL-60 cells were killed within 3 days p.i. There were no significant differences between infected HL-60 and K-562 cells in the efficiency of infection determined at 8 hr p.i. by the indirect immunofluorescent technique, the rate of virus growth, or the amount of viral capsid protein synthesized. This indicated that there were similar viral replication cycles in the two cell lines. These observations suggest that the killing function of the virus is expressed more slowly in K-562 cells than in HL-60 cells.

Congenital rubella. Monoclonal antibody-defined T cell abnormalities in young adults

In order to determine if congenital rubella infection is associated with persistent T cell abnormalities, T cell subsets were quantitated in 16 non-institutionalized subjects (ages nine to 21) with the clinical stigmata and history of congenital rubella. Flow cytometric analysis revealed a decreased T4/T8 ratio (mean +/- SEM in subjects with rubella, 1.57 +/- 0.15, p less than 0.01; in normal subjects, 2.3 +/- 0.4; in subjects with type I diabetes, 2.3 +/- 0.3), decreased percent of T4-positive "helper" cells (42.6 +/- 2.3) different from that in both normal subjects (52.6 +/- 2.4, p less than 0.01) and subjects with recent-onset diabetes (51.5 +/- 2.4), and increased percent of T8-positive "suppressor/cytotoxic" T cells (29.9 +/- 1.4, p less than 0.02) relative to that in normal subjects (24.2 +/- 1.5) and subjects with type I diabetes (23.9 +/- 1.4). Five of 16 subjects with congenital rubella had an elevation of la-positive T cells. Approximately 20 percent had antimicrosomal antibodies. One subject had diabetes mellitus and hypothyroidism, one had hypoglobulinemia, and one had previously undiagnosed hyperthyroidism. Glycosylated hemoglobin levels were normal in all except the diabetic subject, and none of the subjects was islet cell antibody-positive. The T cell abnormalities documented may predispose persons with congenital rubella to the development of organ-specific autoimmunity.

A rapid, simple method for leukemia immunophenotyping using air-dried blood and bone marrow smears

This paper describes a modification of the peroxidase technique by which immunophenotyping may be carried out on routinely air-dried blood and bone marrow (BM) smears. The method is simple and quick, requires no special equipment, can be performed on fresh or stored specimens and gives a standard of morphological detail equal to that of routine blood films. With a monoclonal anti-HLA-DR antibody as a prototype, it was possible to demonstrate reliably, the presence of positively and negatively stained cells of appropriate morphological types in the peripheral blood of leukemia patients. Although only about one-third of antibodies tested were effective with the technique, we identified monoclonal antibodies capable of demonstrating myelomonocyte, granulocyte, monocyte, pan-leukocyte, transferrin, platelet, pan-T, 'cALLA plus B cell' and other antigens. However, we have not yet found antibodies able to identify T cell subsets, nor to distinguish 'common' acute lymphoblastic leukemia from its rare B-cell counterpart. With these limitations the method is suitable for routine use alongside cytochemistry in the differential diagnosis of leukemias and lymphomas.

Monoclonal antibodies identify phenotypically and functionally distinct cell types in the bovine lymphoid system

Monoclonal antibodies were produced against bovine lymphoid cells. The reactivities of the antibodies for membrane determinants were examined on both cell suspensions and cryostat tissue sections prepared from bovine blood, thymus, spleen and lymph nodes. The antibodies were putatively grouped into sets which reacted with monomorphic and polymorphic determinants associated with bovine class I and class II major histocompatibility complex (MHC) antigens (MAbs P12 and P3, and R1 and P2 respectively), or associated with differentiation antigens expressed on T cells and monocytes (MAb P5) or exclusively on monocytes (MAb P8). The antibodies were used to identify the surface phenotypes of cells which stimulate (R1+ P5+ P8+) and proliferate (R1- P5+ P8-) in the bovine mixed leukocyte cultures, and cells which proliferate in response to the mitogen, concanavalin A (R1- P5+).

HLA-DR antigen detection in giant cell lesions

Sixty-six giant cell lesions ranging from inflammatory to neoplastic were evaluated for HLA-DR antigens using formalin/paraffin tissue and a monoclonal antibody labelled by the avidin-biotin peroxidase. HLA-DR antigens were expressed in nearly all lesions, predominantly on round, macrophage-like cells. Granulomatous inflammatory lesions were generally more immunoreactive than non-inflammatory lesions. Multinucleate giant cells were relatively unreactive in non-inflammatory lesions as compared to inflammatory lesions. Determination of HLA-DR expression does not appear to be helpful in discriminating between the various giant cell lesions.

Mononuclear cells in myopathies: quantitation of functionally distinct subsets, recognition of antigen-specific cell-mediated cytotoxicity in some diseases, and implications for the pathogenesis of the different inflammatory myopathies

Monoclonal antibodies reactive for B cells, T cells, T-cell subsets, killer (K) and natural killer (NK) cells, and the Ia antigen were used to analyze mononuclear cell subsets in scleroderma (SD), dermatomyositis (DM), polymyositis (PM), inclusion body myositis (IBM), Duchenne dystrophy (DD), and normal muscle. The analysis, which was quantitative, was performed according to diagnosis and site of accumulation. Cells at perivascular, perimysial, and endomysial sites of accumulation, and cells focally surrounding and invading nonnecrotic muscle fibers, were analyzed separately. Individual antigens were localized in 2-micron serial sections, or multiple antigens were demonstrated in a given section by sequential paired immunofluorescence. The latter approach allowed the identification of the cell phenotypes in which functional properties are defined by multiple markers, e.g., T8+ and T4+ cells that are either activated or not activated, T8+ cells that are either cytotoxic or suppressor T cells, and K/NK cells of varying maturity and killing capability. The interactions of inflammatory cells of various types with each other and the muscle fiber were further investigated by immunoelectron microscopy. In SD, the findings provide evidence for a cell-mediated immune effector response against a connective tissue and/or vascular element. In DM, the effector response appears to be predominantly humoral. In PM and IBM (but not in DM or SD), there is invasion and destruction of nonnecrotic muscle fibers by cytotoxic T cells, with or without accompanying macrophages. Because T-cell-mediated injury is antigen- and major histocompatibility complex-restricted, clones of T cells must have been sensitized previously to a muscle fiber-associated surface antigen. The identity of the putative antigen(s) remains an important, unsolved question.

Predictive value of bronchoalveolar T cell subsets for the course of pulmonary sarcoidosis

To study the value of knowing the proportions of bronchoalveolar T cell subsets when predicting the course of pulmonary sarcoidosis, we subjected 31 patients to clinical, physiologic, and radiographic evaluations, with controls, for at least 12 months. Initially, when all patients were untreated, BAL's were performed, and BAL lymphocyte subsets were marked by the following monoclonal antibodies: OKT3 (expressed by all T cells), OKT4 (to mark helper-inducer T cells), OKT8 (to mark suppressor-cytotoxic T cells), and OKIa (to mark Ia antigen-positive, activated T cells). A normal T4/T8 ratio was highly predictive of a favorable course: the conditions of 13 out of 15 patients with normal ratios remained stable or improved, and only 2 of these 15 patients had to be treated because of persistent symptoms. On the other hand, the conditions of 10 out of 16 patients with elevated T4/T8 ratios deteriorated during the follow-up period. The specificity of T cell subsets for predicting deterioration was improved by considering both the T4/T8 ratio and the number of Ia antigen-positive, activated T cells present. Deterioration occurred in 9 out of 11 patients with elevated T4/T8 ratios and elevated levels of activated T cells. These results suggest that the subtyping of BAL lymphocytes may be useful in determining prognosis in pulmonary sarcoidosis.

Expression of HLA-DR antigen on retinal pigment epithelial cells in retinitis pigmentosa

Class II (HLA-DR) antigens are cell surface molecules that play a major role in the initiation and perpetuation of immune responses. Although most cells do not constitutively express class II antigens, selected cells can be stimulated to do so in some immunologically mediated disorders. When retinal pigment epithelial cells were evaluated by either immunoperoxidase or immunofluorescent staining of frozen eye sections from normal individuals, HLA-DR antigens were not detected. In contrast, retinal pigment epithelial cells from two patients with retinitis pigmentosa did express HLA-DR antigens. These findings demonstrated that at some time during the course of retinitis pigmentosa, the retinal pigment epithelial cell is activated to express HLA-DR.

Sympathetic ophthalmia. Immunopathological findings

Ocular tissue from six patients with a clinical diagnosis of sympathetic ophthalmia (SO) was examined using immunohistochemical techniques. All patients presented with a history of bilateral panuveitis after penetrating ocular injury or multiple intraocular surgeries and clinical features of SO. In four cases, classic histopathological features of SO were observed, including granulomatous uveal tract infiltration and subretinal pigment epithelium (RPE) collections of inflammatory cells (Dalen-Fuchs nodules). Bone marrow derived monocytes were the major cellular components in these granulomas. In two cases, histopathology failed to demonstrate typical Dalen-Fuchs nodules or granulomas in the choroid. However, the choroidal infiltrates were composed primarily of T-helper and B lymphocytes, without macrophages or epithelioid cells. The eyes examined in this report indicate that a varied spectrum of immunopathological and histopathological findings may occur in clinically diagnosed SO.

Ontogenic and functional implications of the differential expression of HLA-DQ antigens on leukemic cells

We have examined the HLA class II antigenic profiles on different types of leukemic cells and have attempted to relate these findings to the normal differentiation pathways of the cells from which they have arisen. Monoclonal antibodies reacting with the different HLA class II determinants, HLA-DR, DRw52(MT), and DQ, were used to study the expression of these antigens on Epstein-Barr virus transformed cell lines, chronic lymphocytic leukemic cells, acute lymphoblastic leukemic blasts, acute myeloblastic leukemic blasts, and established leukemic cell lines by indirect immunofluorescence binding and immunoprecipitations. The results showed that whereas the HLA-DR and HLA-DRw52(MT2) antigens are normally expressed on the majority of the cells tested, there is a different expression of the HLA-DQ antigens on acute leukemic blasts, chronic lymphocytic leukemic cells, and leukemic cell lines indicating that the DQ molecules may be differentiation antigens preferentially expressed on mature cells. Furthermore, when the pre-B cell leukemic line NALM 6 was induced to differentiate with phorbol ester (TPA), normal expression of the HLA-DQ antigen was obtained after 5 days of culture. The absence of HLA-DQ antigens from the acute leukemic blasts suggests that these immature cells "froze" in the early stages of cell differentiation. We discuss these findings in relation to the role of these HLA class II antigens in cell differentiation and the immune response.

Characterization of monoclonal antibodies directed against swine leukocytes

Hybridomas were produced from fusions of the SP2/0 mouse myeloma with splenic cells from: 1) an outbred Sprague Dawley rat immunized with swine peripheral blood mononuclear (PBM) cells; 2) a (CBA/NDub X BALB/c Dub) F1 mouse immunized with concanavalin A (Con A) activated swine PBM cells and 3) a (BALB/c Dub X C3H/He Dub) F1 mouse immunized with swine thymocytes. The resulting supernatants were screened by a microcytotoxicity assay for activity against swine PBM cells. Four hybridomas (MSA1, MSA2, MSA3 and MSA4) were selected, cloned and characterized by their cell reactivity and effect on mitogenic assays. MSA1 and MSA2 belong to the rat IgG2b subclass. MSA3 and MSA4 are of the mouse IgG2a subclass. These monoclonal antibodies reacted in the following manner: MSA1 with monocytes, granulocytes, red blood cells and bone marrow cells; MSA2 with subset of T cells; MSA3 with B cells and subsets of T cells and monocytes (class II molecule) and MSA4, a pan-T cell reagent (E-rosette receptor). The involvement of the various cell types reactive to the different monoclonal antibodies in the mitogenic response of swine PBM cells to Con A, phytohemagglutinin (PHA) or pokeweed mitogen (PWM) was investigated by cellular depletion with monoclonal antibody plus complement. Cellular depletion of PBM cells with the following monoclonal antibodies plus complement treatment resulted in: MSA1, almost total reduction in the mitogenic response to low doses of Con A or PWM; MSA2, partial reduction in the proliferative responses to any concentration of Con A, PHA or PWM; MSA3, partial reduction in proliferative responses to low concentrations of Con A or PWM and 4) MSA4, total elimination of any proliferative response to Con A, PHA or PWM.

Interactions of 1,25-dihydroxyvitamin D3 and the immune system

A series of recent discoveries indicate that the hormonal form of vitamin D3, namely, 1,25(OH)2D3 plays a role in the regulation of the immune system. Cells of the monocyte/macrophage lineage possess receptors for 1,25(OH)2D3 regardless of their activation stage; cells of the lymphoid lineage also express these receptors but only at certain stages of their differentiation pathway and upon activation. Further, 1,25(OH)2D3 promotes the differentiation of monocyte precursors towards monocyte/macrophages and enhances monocyte function in antigen presentation. In addition 1,25(OH)2D3 is a potent inhibitor of interleukin-2 (IL-2) and suppresses effector functions of both T and B lymphocytes via IL-2-dependent as well as via IL-2-independent mechanisms. The theoretical and clinical implications of these discoveries are discussed.

Expression of Ia antigens on the surface of human oligodendrocytes and astrocytes in culture

Oligodendrocytes and astrocytes were isolated from normal adult human brains 3-15 h postmortem using a Percoll density gradient centrifugation and were cultured for 10-135 days. The presence of HLA-DR(Ia) antigens on the surface of these human oligodendrocytes and astrocytes was studied using double immunofluorescence procedures. Only half of separate culture series (6/12 donors) contained HLA-DR-positive oligodendrocytes, while all of the culture series (12/12 donors) revealed HLA-DR-positive astrocytes. Among the HLA-DR-positive cultures, 4-16% of galactocerebroside-positive oligodendrocytes and 9-24% of GFAP-positive astrocytes were found to immunoreact with HLA-DR antibody. The presence of Ia antigens on the surface of certain populations of oligodendrocytes and astrocytes may be important in the induction of an immune response to these cells.

HLA and genetic predisposition to lupus erythematosus and other dermatologic disorders

Human leukocyte antigen (HLA) associations with different clinical and serologic subsets of lupus erythematosus are providing important clues to genetic predisposition and pathogenesis. The evolving complexity of the HLA-D region is described, and currently recognized HLA-region associations with systemic lupus erythematosus, subacute cutaneous lupus erythematosus, homozygous C2-deficient lupus, Sjögren's syndrome, and the neonatal lupus syndrome are reviewed. The striking relationship between the Ro/SSA-La/SSB antibody responses and HLA-DR2 and DR3 are emphasized. Other dermatologic conditions associated with HLA are also noted.

The expression of Ia-antigen on nasopharyngeal carcinomas xenografted into nude mice

The expression of Ia-antigen on four different Epstein-Barr virus associated nasopharyngeal carcinomas xenografted into athymic mice could be detected by the monoclonal antibody OKIa. Xenografts of four additional head and neck tumors other than nasopharyngeal carcinoma and one xenograft of a metastatic melanoma cell line were negative for the Ia-antigen. Control antibodies OKT3, OKT4, OKT9, OKM1 and Leu7 were negative with all nasopharyngeal carcinomas and the non-nasopharyngeal carcinoma xenografts. Complement receptors as the presumed receptors for the Epstein-Barr virus could not be detected on xenografted nasopharyngeal carcinoma cells but were found on freshly prepared peripheral blood lymphocytes as well as on the Epstein-Barr virus transformed lymphoblastoid cell line QIMR-WIL. The possible role of the Ia-antigen on nasopharyngeal carcinoma cells in respect to the Epstein-Barr virus association of this malignancy is discussed.

HLA-DR expression in a human colonic carcinoma cell line

A human colonic carcinoma cell line (HCA-7) isolated from a well differentiated mucoid adenocarcinoma of the colon has been maintained in vitro for 3 years. It spontaneously synthesizes HLA-DR which is mainly intracytoplasmic. Stimulation with lymphocyte conditioned medium and recombinant gamma-interferon results in enhanced synthesis of HLA-DR and the appearance of the antigen on the cell surface. A dose response study showed that maximal stimulation of the culture was achieved with 50 units/ml of recombinant gamma-interferon. Staining for HLA-DR was uneven being confined to focal areas of the monolayer, which is similar to the focal expression of HLA-DR seen in sections of adenocarcinoma of the colon. The functional significance of this phenomenon is unclear, but it may explain the presence of lymphoid infiltrates in tumours.

A sensitive method for immunophenotyping stored leukemia and lymphoma cells with preservation of morphological detail

We describe a method by which density-separated mononuclear preparations of blood and bone marrow may be stored and batch-processed for immunophenotyping by the indirect immunoperoxidase (IP) technique. The method gives excellent preservation of cellular detail thus permitting clear morphological categorization of IP-positive and IP-negative cells. We compared the immunofluorescence (IF) and IP techniques for estimation of the proportions of cells displaying a variety of antigens; with normal blood cells the results were closely similar but with chronic lymphocytic leukemia (CLL) cells, IP was superior to conventional IF. Using 910 D7, a new anti-la antibody, we were able to observe directly the presence of la-positive lymphocytes and monocytes in normal peripheral blood and la-positive granulocyte precursor cells from 2 cases of chronic granulocytic leukemia (CGL) in transformation. The method is useful for immunophenotyping of cases of lymphoproliferative disorder (LPD) and for morphological identification of specific antigen-positive cells.

A case of T-cell chronic lymphocytic leukemia with an unusual phenotype and central nervous system involvement

A case of T-cell chronic lymphocytic leukemia is reported. The leukemic cells had the morphologic features of medium-sized, mature-looking lymphocytes, and had an affinity for the central nervous system. Cytochemically, they were positive for alpha-naphthyl acetate esterase and acid phosphatase. They formed E-rosettes (E+) and reacted with OKT11 but not with OKT3/Leu-4, OKT4/Leu-3, OKT8/Leu-2, or OKM1, and did not possess IgG-Fc receptors (Fc gamma R). Functionally, they did not respond to phytohemagglutinin or concanavalin A, were not natural killer cells or antibody-dependent as well as alloantigen-reactive killer cells. Furthermore, they did not possess a helper or suppressor T-cell function for immunoglobulin synthesis. Results of immunologic studies suggest that the leukemic cells were derived from a normal counterpart of a lymphocyte subset present as a minor component of the peripheral blood, namely an E+, OKT3-, OKM1-, Fc gamma R- subset, the function of which is not yet identified.

The modulation of membrane Ia on human B lymphocytes

Using flow cytometry techniques, changes in surface Ia (DR and DS) expression on human B lymphocytes were correlated with changes in the cell cycle following stimulation with anti-mu. The effect of interleukin (IL)-1, IL-2, B-cell growth factor (BCGF), and interferons on Ia expression on resting B cells was also examined. A population of resting B lymphocytes was cultured in vitro with 100 micrograms/ml of anti-mu and immunofluorescently stained for DR and DS at various times following stimulation. Detectable increases in DR and DS expression were found within 8 hr, and the major increases (twofold and fourfold) in DR and DS expression occurred over the next 48 hr. Using cell cycle inhibitors and propidium iodide staining, it was demonstrated that the enhanced DR and DS expression following anti-mu stimulation began during G0 to G1 transition and increased as the cells progressed through G1 phase. During S and G2/M phases, there were minimal further increases in surface Ia. Although prolonged exposure of B cells to anti-mu was required for cellular activation, cell size enlargement, and progression into S phase, a brief exposure to anti-mu, insufficient for cellular activation, markedly enhanced Ia expression. Thus anti-mu-stimulated resting human B lymphocytes rapidly increase their surface Ia expression. This increase occurs predominantly prior to entrance into S phase and can occur in the absence of significant cellular activation. Interferons have been reported to modulate surface Ia expression on a human lymphoid cell line and on monocytes and supernatants with BCGF activity to enhance surface Ia expression on murine B cells; however, neither alpha-interferon, gamma-interferon, IL-1, IL-2, nor BCGF modified surface DR expression on normal resting human B cells.

Autologous mixed lymphocyte reaction in man. XIII. Characterization of the T-T autologous mixed lymphocyte reaction

In this study we have demonstrated that in the T-TA autologous mixed lymphocyte reaction (AMLR), OKT4+ T cells are the major responders; however, in the presence of additional interleukin-2 (IL-2), OKT8+ T cells also respond by proliferation. Both OKT4+ and OKT8+ T cells, activated in the T-non-T AMLR, act as stimulators in the T-TA AMLR. OKT4+ T cells activated in the T-TA AMLR suppress the proliferative response of the fresh T-non-T AMLR; control OKT4+ cells show no immunoregulatory activity in this system. In contrast, control OKT8+ T cells spontaneously suppress the proliferation of the T-non-T AMLR, but activation of OKT8+ T cells in the T-TA AMLR does not result in a further increase in the suppressor activity of OKT8+ T cells. In summary, in the T-non-T and T-TA AMLR phenotypically similar T-cell subpopulations proliferate but express distinct immunoregulatory functions and perhaps regulate the tempo of the AMLR.

Immunohistochemical analysis of human MHC class II antigens in B-cell non-Hodgkin's lymphomas

Twenty cases of B-cell non-Hodgkin's lymphoma (NHL) were evaluated by immunohistochemical staining of frozen sections with a panel of anti MHC class II monoclonal antibodies (MCA). These studies showed marked differences in the expression of class II antigens both between different cases and within the population of cells of individual cases. In all of the cases studied the majority of the tumour cells reacted with MCAs directed against determinants common to the products of SB and DR loci. However, MCAs specific for DC determinants failed to react with 3/20 cases and in several other cases stained only a minority of cells. Absent or reduced expression of DC antigens was most marked in lymphocytic lymphoma; however, in centroblastic-centrocytic and centroblastic lymphomas, DC antigens could be detected on the majority of cells.

Osteosarcomas and Ewing's sarcomas. Comparative immunocytochemical investigation of filamentous proteins and cell membrane determinants

Primary malignant bone tumors, osteosarcomas (9 cases), and Ewing's sarcomas (10 cases) were examined for their reactivities with monoclonal and polyclonal antibodies against filamentous proteins and cell membrane determinants of the lymphoid and macrophage marker series. The reactivity of antibodies was studied on snap-frozen tissue probes by using a triple layer immunoperoxidase method. Osteosarcomas were positive for vimentin and, in part, for HLA-DR. Other types of intermediate-sized filaments were not detected in tumour cells. In a small number of cases (2/9) tumour cells were reactive with antibodies of the macrophage series (Leu M2). In Ewing's sarcomas, vimentin and HLA-DR was also demonstrated. It was particularly interesting that Leu M2 staining was found in the majority of cases (8/10). The staining pattern supports the assumption that this peculiar tumour is of mesenchymal (monocyte/macrophage) histogenesis. It was evident from the present study that, in primary osteogenic tumors, none of the examined tumour "markers" were as distinctive as they are for bone metastases. Nevertheless, the reactivity of Ewing's sarcoma cells with monoclonal antibodies of the Leu M2 type throws some highlights on the, as yet, obscure histogenesis of the neoplasm and may be of diagnostic value in conjunction with the known light and electron microscope features of the tumour.

Electrophoretic variation between class II molecules expressed on HLA-DRw8 homozygous typing cells reveals multiple distinct haplotypes

Two-dimensional (2D) gel electrophoresis of immunoprecipitated HLA-DR antigens from eight homozygous typing cells (HTC) expressing the HLA-DRw8 specificity revealed a clustering of polymorphic beta chain patterns into distinct electrophoretic variants. The variant patterns correlate with three discrete HLA-D clusters that are defined in the mixed leukocyte culture reaction (MLR) using DRw8-positive HTC. These HLA-D clusters have been provisionally designated Dw"8.1", detected primarily in Caucasoids, Dw"8.2", detected primarily in American Indians, and Dw"8.3", detected predominantly in Orientals. All three HLA-Dw"8.1" cell lines express a single DR-locus product as defined by immunoprecipitation with a DR-specific monoclonal antibody, P4.1. This DR beta chain is identical among the Dw"8.1" cell lines and different from the DR beta chains of the Dw"8.2" and Dw"8.3" cell lines. Two separate Dw"8.2" HTC express a shared DR beta chain that is slightly more basic than the 8.1 DR molecule; interestingly, one of these lines also expresses an additional DR-like beta chain not found in the other cells. Thus, the two lines defining the Dw"8.2" cluster share one distinct class II molecule, but differ in another and therefore are not biochemically HLA-identical. Cells from the Dw"8.3" cluster are likewise distinct from all other Dw8 clusters. One additional DRw8-positive HTC has been analyzed and found to be distinct from the Dw"8.1", "8.2" and "8.3" clusters by both MLR and 2D gels. Immunoprecipitates using monoclonal antibody 1B5 [anti-DR and anti-DQ(DS)] identify additional polymorphic class II variants among the cell lines tested. These data indicate that HLA-DRw8 is a public serologic specificity present on class II molecules expressed on multiple distinct haplotypes. These haplotypes differ from each other in expression of polymorphic class II molecules encoded by at least two HLA loci. They also differ in HLA-D, even though they all type as HLA-DRw8 homozygous. In Dw"8.2", variation in expressed beta chains is not reflected in variation in HLA-D, indicating that MLR, as well as serologic typing, does not detect the full degree of allelic polymorphism within HLA.

Ia-positive T lymphocytes in recently diagnosed idiopathic Addison's disease

The Ia (DR, immune-associated) antigen is absent on normal circulating T lymphocytes, but present on activated T lymphocytes. Utilizing monoclonal antibody L243, the expression of this glycoprotein on circulating T lymphocytes was studied in five patients with recent-onset idiopathic Addison's disease, one patient with recent-onset adrenal hemorrhage, and nine patients with long-standing adrenal insufficiency (five with idiopathic Addison's disease and four after bilateral adrenalectomy for Cushing's disease). The patient with adrenal hemorrhage and the nine patients with long-standing adrenal insufficiency had percentages of circulating Ia-positive T cells within the normal range. All five patients with recent-onset idiopathic Addison's disease had an elevated percentage of circulating Ia-positive T cells (7 to 29 percent). The expression of Ia antigen on T cells in recent-onset idiopathic Addison's disease probably reflects immunologic activation, which may be of pathophysiologic importance.

Adenolymphoma: an immunohistochemical study with monoclonal antibodies against lymphocyte antigens

Twenty-two adenolymphomas (Warthin's tumours) were investigated with respect to their lymphoid stroma; 4 were analyzed by monoclonal antibodies against B-cells and T-cells. A slight predominance of B-cells was found. In the T-cell fraction, the T-helper cells outnumbered the T-suppressor cells by a factor of 4. These and other cell types were found in the stroma and in the epithelium. Mast cells were associated with those adenolymphomas having a high proportion of epithelium.

Monoclonal antibody analysis of mononuclear cells in myopathies. I: Quantitation of subsets according to diagnosis and sites of accumulation and demonstration and counts of muscle fibers invaded by T cells

In 76 muscle specimens (normal controls, 9; Duchenne dystrophy, 11; scleroderma, 11; dermatomyositis, 13; polymyositis, 15; inclusion body myositis, 17), mononuclear cells were analyzed at perivascular, perimysial, and endomysial sites of accumulation. Monoclonal antibodies reactive for B cells, T cells, T cell subsets, killer (K) or natural killer (NK) cells, and the Ia antigen were used for cell typing. Macrophages were identified by the acid phosphatase reaction. Few extravascular mononuclear cells occurred in normal muscle. In all inflammatory myopathies, a mixed exudate of T cells, B cells, and macrophages was present. Mature K/NK cells were rare in all diseases. In dermatomyositis, polymyositis, and inclusion body myositis, there was a positive gradient for T cells, T8+ cells, and activated T cells and a negative gradient for B cells and T4+ cells between perivascular and endomysial sites. In scleroderma the predominant perimysial exudate consisted mostly of T cells and macrophages. The percentage of B cells at all sites, and the T4+/T cell ratio in the endomysium, were significantly higher in dermatomyositis than in the other diseases. In polymyositis and inclusion body myositis, the endomysial exudate contained a large number of T cells, T8+ cells, and activated T cells but only sparse B cells. T cells accompanied by macrophages focally surrounded and invaded nonnecrotic fibers in polymyositis and inclusion body myositis. Rare fibers in Duchenne dystrophy and a very few fibers in dermatomyositis and scleroderma were similarly affected. We infer that (1) T-B, T-T, and T-macrophage cooperativities are likely to exist in muscle in different myopathies; (2) T cell-mediated fiber injury plays a role in polymyositis and inclusion body myositis; (3) T cell-mediated fiber injury can also occur in inherited diseases, such as Duchenne dystrophy; and (4) a local humoral response may occur in muscle in dermatomyositis and possibly in polymyositis and inclusion body myositis.

Monoclonal antibody analysis of mononuclear cells in myopathies. II: Phenotypes of autoinvasive cells in polymyositis and inclusion body myositis

In 6 cases of polymyositis and 6 of inclusion body myositis, phenotypes of mononuclear cells focally surrounding and invading muscle fibers were analyzed. By localizing the T8, T4, and Ia markers with direct immunofluorescence and acid phosphatase enzyme cytochemically in the same sections, five different phenotypes were simultaneously identified in a given section: T8+ and T4+ cells that were either activated (Ia+) or not activated (Ia-), and acid phosphatase--reactive and Ia+ macrophages. This approach permitted the separate and quantitative assessment of the distributions of the different phenotypes among the invading versus the surrounding cells. In both polymyositis and inclusion body myositis, the invading cells were selectively enriched in the T8+ phenotype. One-third of all invading cells and one-half of the invading T8+ cells were activated. T4+ cells were more abundant among the surrounding than the invading cells, and only a small proportion of the T4+ cells were activated. These findings are especially significant in view of the cytotoxic capability of the T8+ cells and because histocompatibility factors permit T8+ but not T4+ cells to recognize an antigen on muscle fibers. Macrophages accounted for 21 to 31% of the cells invading or surrounding nonnecrotic fibers. For purposes of comparison, we also analyzed mononuclear cells in necrotic fibers: 80% of these cells were macrophages, and only 20% were T cells. The findings indicate that in polymyositis and inclusion body myositis, nonnecrotic muscle fibers are injured by autoinvasive T8+ cells that act in concert with macrophages. Further, the findings strongly imply previous sensitization of clones of T cells to muscle fiber-associated surface antigen(s).

Study of activated T cells in man. I. Discrepancy between Tac antigen and DR Antigen on T cells in patients with primary immunodeficiency

DR and Tac antigens are present on T cells activated in vitro with mitogens and antigens but lacking on resting T cells. Freshly prepared peripheral blood T cells from patients with common variable immunodeficiency ( CVI ) and isolated IgA deficiency ( IAD ) were examined for the presence of DR and Tac antigens, using monoclonal antibodies and a fluorescence-activated cell sorter. Both Tac+ and DR+ T cells were significantly (P less than 0.05) increased in the patient group when compared with age- and sex-matched controls; however, a discrepancy was observed in the proportions of Tac+ T cells and DR+ T cells. This study demonstrates that, in certain patients with CVI and IAD , T cells are activated in vivo, and Tac and DR antigens could be expressed during different stages of T-cell activation.

HLA and GM in insulin-dependent diabetes in the Netherlands: report on a combined multiplex family and population study

This report deals with the genetic factors involved in insulin-dependent diabetes mellitus (IDD) in The Netherlands. Twenty-two Dutch multiplex families with IDD were typed for HLA-A, -B, -C, and -DR antigens, for BF, C2, C4, and GLO polymorphisms, as well as for GM allotypes of immunoglobulins. In addition, 53 unrelated IDD children and 31 unrelated patients with adult onset IDD were typed for HLA-A, -B, -C, and -DR antigens. A significant heterogeneity for the frequency of HLA-DR4 related to age of onset was observed. A significant deviation of the Hardy-Weinberg equilibrium was observed for the HLA-DR locus with an excess in patients of heterozygotes HLA-DR3, -DR4.HLA-B8, and HLA-B15 were not only secondary associated, but constituted with HLA-DR3 and -DR4, respectively, a haplotype in association with IDD. Nonrandom segregation of HLA-haplotypes was observed in multiplex families exemplified by an excess of HLA-identical affected sibpairs . Cross- overs between HLA-DR and GLO identified the HLA-DR segment as mainly involved in the association with IDD. Three diabetic haplotypes were confirmed to occur frequently among affected sibs: (a) A1, B8, BFS, C2.1, C4AQO , C4B1 ,DR3, GLO2 ; (b) Aw30, Cw5 ,B18,BFF1,C2.1, C4A3 , C4BQO ,DR3, GLO2 ; (c) A2,Cw3, B15,BFS, C2.1, C4A3 , C4B3 , DR4,GLO1. The segregation of GM allotypes to affected sibpairs was not significantly different from random segregation. The main conclusions from this study are that significant heterogeneity for age of onset exists and that the data are not compatible with simple genetic models including dominant, recessive, and intermediate models of inheritance. The data do require more complex models, involving two different HLA-linked (sets of) susceptibility genes.

HLA-DC antigens can serve as recognition elements for human cytotoxic T lymphocytes

The specificity of four cytotoxic T lymphocyte (CTL) clones which recognize class II major histocompatibility complex (MHC) antigens was analyzed. All clones recognized antigens associated with the serologically defined HLA-DRw6 specificity. The activity of two of these clones, JR-2-2 and JR-2-10, could be inhibited by a monoclonal antibody Q 5/13 specific for a monomorphic determinant present on HLA-DR. In contrast, the activity of the two other CTL clones, JR-2-19 and JR-2-26, was not blocked by Q 5/13, but by a new monoclonal reagent, SPV-L3. This latter monoclonal antibody precipitated a two-chain structure of 28 kDa and 33 kDa and reacts with a monomorphic determinant. The molecular weight of the polypeptides precipitated with SPV-L3 was slightly less than those precipitated with a HLA-DR-specific monoclonal reagent. In addition two-dimensional gel electrophoresis showed that the antigen precipitated by SPV-L3 differed in charge from those precipitated with the anti-HLA-DR antibody. These results indicate that SPV-L3 recognizes a class II MHC product different from HLA-DR. This observation was confirmed by partial amino acid sequence analysis of the two chains which revealed that the molecule precipitated by SPV-L3 is homologous to HLA-DC/DS molecules. Therefore this report provides the first evidence that human cytotoxic T cells can recognize HLA-DC/DS antigens.

T-cell proliferation and expression of MHC class II antigens

Two monoclonal antibodies to major histocompatibility complex (MHC) class II antigens, which in combination identify beta chains encoded by the SB and DR loci, were used to investigate which of these gene products were expressed at the cell surface of unstimulated T cells and at various stages of mitogen-induced T-cell maturation. In tests on blood lymphocytes from healthy donors 12% of T cells expressed class II antigens, but only SB antigens were expressed. During activation of T lymphocytes, SB-coded antigens were expressed before DR antigens, and the kinetics of SB expression correlated with the proliferative response of T cells. These results and consideration of recent reports from other laboratories lead us to suggest that SB-coded class II antigens play a role in T-cell proliferation.

Colony assays of hematopoietic progenitor cells and correlations to clinical situations

The production of blood cells is a dynamic process that is noticeably aberrant during disease. The availability of colony assays in vitro that allow detection of hematopoietic stem and progenitor cells for the neutrophil, monocyte-macrophage, erythroid and/or megakaryocyte lineages has been of importance for the present understanding of the mechanisms controlling the proliferation, self-renewal capacity, and differentiation of morphologically nonrecognizable immature cells which give rise to the mature progeny circulating in the blood. It is through the use of these assays that the existence of potentially relevant stimulatory and inhibitory feedback interactions has been demonstrated. Abnormalities in these interactions, which may be of significance during leukemia and related disorders, have been uncovered. This communication will discuss regulatory interactions detected via the colony assays, their potential relevance physiologically and pathologically, and the use of these assays for diagnosis, prognosis, and for monitoring the clinical status of patients.