Monosomy 6 in a human lymphoma line induced by selection with a monoclonal antibody

The human Epstein Barr Virus-superinfected B lymphoma cell line BJAB-B95.8.6 was mutagenized by gamma irradiation, and HLA mutants were selected with the HLA-Bw6-specific monoclonal antibody SFR8-B6. One of the mutants obtained, BM19, had lost one of the chromosomes 6 present in the wild type cells. Electrophoretic analysis of phosphoglucomutase isozyme PGM3 and erythrocyte glyoxalase 1 from both cells supports this conclusion. The HLA antigens expressed on BM19 were HLA-A2, B13, Bw4, C-, DR2 (questionable), DRw52 (weak) and DQw1. This constitutes one of the haplotypes of the wild type cells, the other (lost from BM19 cells) being HLA-A1, B35, Bw6, Cw4, DR5, DRw52 (strong) and DQw3. Possibilities to employ BM19 cells for the analysis of the major histocompatibility complex and other chromosome 6-encoded genes as well as their products are discussed.

Expression of HLA-A and -B antigens on differentiating U-937 cells

Cells from the human immature monocytoid cell line U-937 were induced with 12-O-Tetradecanoyl-phorbol-13-acetate (TPA) to differentiate towards macrophage-like cells. The expression of HLA-antigens during differentiation was examined with a panel of monoclonal antibodies directed against monomorphic and polymorphic determinants. Class II antigens could be detected neither on uninduced nor on TPA-induced U-937 cells. While the expression of HLA-A3 did not change significantly during differentiation, the "supertypic" specificities HLA-Bw4 and Bw6 as well as the "private" specificity HLA-B18 could be detected only on a drastically decreased number of cells after 4 days of exposure to TPA. This may imply a selective loss of HLA-B molecules from the cell membrane and therefore a separate regulatory control of HLA-A and -B antigens.

Divergent expression of HLA-DC/MB, -DR, and -SB region products on normal and pathological tissues as detected by monoclonal antibodies

A group of eight monoclonal antibodies directed against different monomorphic determinants of HLA-class II molecules was used to investigate the distribution of HLA-DC/DS/MB, -DR and -SB-like antigens on normal and pathological lymphoid and nonlymphoid tissues of human adult and fetal donors. HLA-MB/DC/DS-like molecules, as defined by the antibody TU 22, showed the most limited distribution as they were detected on B-lymphocytes, monocyte/macrophage subpopulations and distinct interstitial cells of various organs. HLA-DR and -SB-like antigens characterized by the other anti-HLA-class II reagents (TU34, TU35, TU37, TU39, TU43, TU58) were also present on these cell types. However, selective expression of HLA-DR and/or -SB like molecules was demonstrated with these antibodies on certain vascular endothelia, as well as different B-cell lymphomas and distinct epithelial cells in adults. Exclusive reactivity of the antibody TU39 shown on endothelial cells of fetal liver and kidney suggested specific functions of HLA-SB antigens during ontogeny. Furthermore, HLA-DR and/or -SB like molecules but not TU22+ HLA-DC/MB antigens were found to be inducible on normally Ia-like antigen negative epithelial cells of various diseased organs. Implications of this differential tissue distribution of HLA-DC/MB/DS, -DR and -SB like products in relation to organ transplantation, regulation of immune responses and cell differentiation are discussed.

Specificity of monoclonal antibodies directed against human and murine class II histocompatibility antigens as analyzed by binding to HLA-deletion mutant cell lines

The specificity of 70 monoclonal anti-Ia monoclonal antibodies (MoAbs) (18 mouse allo-induced and 52 rodent anti-human) was studied with a panel of 17 HLA-deletion mutants that were derived from a single parent line and vary in expression of Ia antigens due to deletion of different subregions of HLA. MoAb binding was analyzed both by ELISA and flow microfluorometry. Characterization of the MoAbs with respect to specificity for products of subregions of a DR1-DC1-SB2 haplotype revealed great complexity. Many antibodies were quite specific for DR-linked determinants (26 MoAbs), DC-linked determinants (5 MoAbs), or determinants indistinguishable from SB (4 MoAbs). However, many MoAbs bound to products of more than one subregion: DR + SB (+/- weak DC) (22 MoAbs); DR + DC (3 MoAbs); or DR + DC + SB (1 MoAb). Furthermore, a number of the MoAbs bound unequally to products of the two HLA haplotypes analyzed, particularly among those recognizing DC1-linked determinants and the murine alloinduced MoAbs. Finally, despite strong structural homologies of murine I-A to human DC and murine I-E to human DR, the intraspecies cross-reactions of MoAbs do not closely follow that pattern. These data: (1) illustrate the usefulness of HLA-deletion mutant cell lines for analysis of the specificity of MoAbs and for delineation of HLA subregions; (2) demonstrate the great diversity of MoAbs specific for class II molecules and the high frequency of MoAbs that bind to products of more than one Ia subregion, particularly DR and SB. In view of such complexity, many (perhaps most) MoAbs cannot be relied on to unambiguously identify products of a particular Ia subregion, without extensive characterization.

Dissection of human allostimulatory determinants with cloned T cells: stimulation inhibition by monoclonal antibodies TU22, 34, 35, 36, 37, 39, 43, and 58 against distinct human MHC class II molecules

Alloantigenic determinants causing secondary lymphoproliferative responses of primed T cells were investigated by blocking stimulation with monoclonal antibodies TU22, 34, 35, 36, 37, 39, 43, and 58 binding differentially to HLA-DR and SB or MB associated molecules. In particular, the use of cloned and functionally defined T cell responders greatly facilitated the assignment of stimulator-level inhibition caused by these antibodies. Thus, a novel way of functional "mapping" for stimulatory epitopes for sets of clones with restimulation specificities associated with HLA-D, SB, MB, or hitherto unidentified class II determinants is presented here. This considerably helps to elucidate the distinct immunoregulatory roles of the three major class II alloantigen systems thus far defined.

5'-O-Palmitoyl- and 3',5'-O-dipalmitoyl-5-fluoro-2'-deoxyuridine--novel lipophilic analogues of 5'-fluoro-2'-deoxyuridine: synthesis, incorporation into liposomes and preliminary biological results

5'-O-palmitoyl- and 3',5'-O-dipalmitoyl-5-fluoro-2'-deoxyuridine were prepared by the reaction of 5-fluoro-2'-deoxyuridine in dimethylacetamide with palmitic acid chloride. The incorporation of the synthesized prodrugs into liposomes composed of egg phosphatidylcholine/stearylamine/cholesterol/alpha-tocopherol at a molar ratio of 10:1:2:0.05 was nearly quantitative; homogeneous bilayer vesicles (75 nm diameter) were obtained. Preliminary tolerance studies revealed that the prodrug-liposome preparations are about 20-60 times more toxic than the parent drug. The prodrugs incorporated into liposomes were 10 to 30 times more active against murine colon 38 carcinoma compared to the free drug. In comparison to the administration of the prodrugs in peanut oil the liposomal preparations seem to exert improved effects and represent a valuable drug delivery system for parenteral applications.

Refinement of HLA gene mapping with induced B-cell line mutants

The lymphoma cell line BJAB.B95.8.6 was gamma-irradiated to induce mutations of major histocompatibility complex (MHC) encoded genes. Cloned "wild-type" cells were phenotyped HLA-A1, A2, B13, B35, Bw4, Bw6, Cw4, DR5, DRw52, DQw1, DQw3, DPw2, DPw4, GLO1 1, PGM3 2-1, and ME1 0 and possessed two apparently normal chromosome 6s prior to mutagenesis. Loss mutants were selected 5 days after 3 Gy gamma-irradiation employing three complement-fixing monoclonal antibodies specific for HLA-A2 (TU101) and Bw4 (TU48, TU109). Fifteen independently arising mutants were isolated and cloned. Typing with monospecific alloantisera and cell-mediated lympholysis revealed the presence of HLA-A1, B35, Bw6, Cw4, DR5, DRw52, DQw3, and DPw4 specificities on all mutant clones. HLA-A2, B13, and Bw4 were absent. Mutants differed in their expression of class II antigens. One group retained DQw1 and DPw2, another was DQw1-, DPw2+, and a third was DQw1-, DPw2-. Karyotyping of the "wild-type" line and selected mutant clones showed that the loss of HLA specificities correlated with deletions which map the HLA-A and -B loci directly to the distal part of the 6p21.33 region and the class II genes to the region 6p21.33 (proximal) to 6p21.31 (distal) on the short arm of chromosome 6.

Psychomental stress in tetraplegic man: dissociation in autonomic variables and emotional responsiveness

Tetraplegic patients with physiologically complete cervical spinal cord transsection are classic ablation models of sympathetic denervation. Therefore this study was conducted to investigate the hemodynamic response (blood pressure, cardiac rate) and the plasma catecholamine (adrenaline, noradrenaline) release induced by a standardized psychomental stress model (sonic confuser). Attention was focussed on subjective evaluation of stress experience in spinal man. During psychomental stress, typical pressure reaction was not observed, cardiac rate was elevated insignificantly, and catecholamine release was diminished. The subjective estimates of stress experience, however, did not differ from those of the control group. It appears that psychomental stress in sympathectomized man is not extinguished despite abolished peripheral autonomic feedback modifying the state of the central nervous system. Cognitive processes and cortical arousal seem to be the initial and important steps of emotional experience and they are independent from peripheral autonomic processes. These results lend support to the centralistic view of emotions and the importance of cognitive factors in emotional responsiveness.

Do monoclonal antibodies Tü15 and Tü67 detect heterogeneity of human transferrin receptor molecules?

The possible molecular heterogeneity of human transferrin receptors was analyzed using two murine monoclonal antibodies, Tü15 and Tü67. Both reagents precipitated from lysates of 125I-labeled HL-60 cells a major component of 88 kDa which could be identified as the transferrin receptor by comparison with the proteins detected by monoclonal antibody OKT9. Although sequential immunoprecipitations appeared to demonstrate molecular heterogeneity of transferrin receptors, since the Tü15-reactive species were fully included in the Tü67-positive population, but not vice versa, the possible association of Tü15-reactive molecules with transferrin receptor is also discussed.

Immature sinus histiocytes. Their identification as a novel B-cell population

The true nature of cells of "immature sinus histiocytosis" (ISH) is uncertain because they lack the typical features of normal histiocytes when analyzed by enzyme cytochemistry or electron microscopy. In the present study the antigenic profile of ISH cells has been analyzed by immunohistologic techniques in six cases of Piringer's lymphadenitis with the use of a large panel of monoclonal and polyclonal antibodies reactive with the major cell types of the hematolymphoid system. The results obtained indicate that ISH cells consistently lack markers found on cells of the monocyte/macrophage series, myeloid cells, interdigitating reticulum cells, follicular dendritic reticulum cells, T cells, or Ki-1-positive cells. They constantly express B-cell antigens and HLA-DR and (on a variable proportion of cells) surface immunoglobulin. The application of antibodies reactive with different B-cell subsets showed that the cells of ISH do not correspond to any previously described B-cell population, eg, pre-B cells, germinal center cells, follicular mantle lymphocytes, or marginal zone cells. Furthermore, ISH cells and germinal center cells are found in association with clearly different cell types. These findings indicate that ISH cells represent a B-cell population at a previously undescribed differentiation stage, occurring only under certain circumstances (eg, in toxoplasmosis or AIDS). It is proposed that the term "immature sinus histiocytosis" be replaced by "B-cell sinus reaction."

The effect of gallamine, gallopamil and nifedipine on responses to acetylcholine and carbachol in the taenia of the guinea-pig caecum

The effects of gallamine, gallopamil and nifedipine on isotonic contractions of the isolated taenia of the guinea-pig caecum produced by acetylcholine (ACh) or carbachol (CCh) were investigated. Gallamine (0.1 to 0.3 mM) inhibited contractions produced by CCh more than those produced by ACh. The difference was still present after pretreatment of the tissue with paraoxon (10 microM for 20 min) to inhibit cholinesterases or in experiments carried out in the presence of tetrodotoxin (0.3 microM) to exclude possible ganglionic stimulation by the agonists. Gallopamil or nifedipine selectively inhibited the tonic response to ACh in the absence or presence of paraoxon. The phasic response to ACh or the tonic response to CCh (0.1 or 1 microM) was much less affected. Reduction of the Ca2+ content of the bath medium reduced phasic and tonic responses to ACh more than the tonic response to CCh. These results suggest that there are differences in the interaction of ACh and CCh with muscarinic receptors in this muscle.

[Interval therapy of migraine. Pharmacological bases]

A quite heterogenous variety of drugs is used for the prophylactic treatment of patients with severe migraine. These drugs may prove effective in preventing migraine attacks due to two different pharmacological effects: a reduction of platelets' aggregability and/or an effect on blood vessels tone. The latter effect may be characterized by a decrease in reactivity, i.e. vasoconstriction as well as an overshooting vasodilation is prevented. The vascular tone is stabilized.

Cardiac glycosides with different effects in the heart

Remarkable differences exist between the effects of different cardiac glycosides (native and semi-synthetic) with respect to the affinity and to the magnitude of inotropic responses and their time courses. At glycoside concentrations which lead to identical Na-K-ATPase inhibitions, the inotropic responses vary widely. This finding contradicts the hypothesis that the increase of contractile force is the consequence of an ATPase inhibition and causally related to it. We propose the hypothesis that the inhibition of ATPase and the inotropic stimulation provoked by cardiac glycosides are two parallel events, not causally related but both mediated by the same receptor. The inhibition of the Na-K-ATPase is the consequence of the occupation and thus proportional to the concentration of the glycoside-ATPase complexes. In contrast, the inotropic response is determined by the frequency of glycoside-ATPase-interactions. Glycosides which possess high association and dissociation rate constants will interact with the ATPase with high frequencies and thus will evoke larger inotropic responses at a given ATPase inhibition than glycosides with low turnover rates.

Phenotypic heterogeneity of leukemic Sézary cells

Leukemic blood cells from eight patients with Sézary's syndrome were analyzed for enzyme cytochemical features, Fc receptors, and surface phenotype. Enzyme cytochemically the cases were heterogeneous in their activity of acid esterase, acid phosphatase and dipeptidylaminopeptidase IV (DAP IV). Only one case showed positive staining for DAP IV. The expression of Fc receptors for IgG and IgM also varied. The DAP IV-positive case exhibited Fc mu receptors. In contrast, four other cases showed only Fc gamma receptors. Analysis of the surface antigen pattern of Sézary cells with monoclonal antibodies revealed the phenotype of helper T lymphocytes (Leu-3 a/OKT4+) in all but one case. The Leu-3 a/OKT4-negative case showed a phenotypic feature of natural killer cells (Leu-7+). The results obtained with the antibodies TU14 and Anti-human Lyt-1 were more heterogeneous. The heterogeneity of Sézary cells may be interpreted as a sign of differences in functional differentiation or of proliferation of different T-cell subclones.

Human dendritic reticulum cells of lymphoid follicles: their antigenic profile and their identification as multinucleated giant cells

The B-dependent areas of human lymphoid tissue contain non-lymphoid, non-phagocytic cells known as dendritic reticulum cells (DRC). These cells can be detected only very occasionally in routinely stained histologic sections. Recently we were able to overcome this limitation by preparing a monoclonal antibody, termed R 4/23, that reacts selectively with DRC. Thus by using an optimized immunoperoxidase method applied to frozen sections, it is possible to detect DRC in situ. To determine the antigenic profile of DRC, serial frozen sections of human tonsils were immunostained with R 4/23 and a large panel of other monoclonal antibodies or conventional antisera. In addition, touch imprints of tonsils and cytocentrifuge slides of cell suspensions with increased concentrations of DRC were immunostained with these reagents. DRC proved to be positive for mu, gamma, alpha, kappa and lambda chains, complement component C3b, C3b receptors, C3d receptors, HLA-A,B,C antigens, human Ia-like antigens, common ALL antigen (cALLa), and antigens that are characteristic of the monocyte/macrophage lineages. DRC did not express delta chains, T cell antigens, or antigens that are expressed on interdigitating reticulum cells (IDC) and Langerhans cells. DRC in touch imprints and suspensions prepared from hyperplastic tonsils were found to be giant cells often with 10 or more nuclei. In certain cases of follicular hyperplasia and of centroblastic-centrocytic lymphoma, DRC with several nuclei were also detectable in situ. These results show that (1) the phenotype of DRC differs from that of all other cell types in lymphoid tissue, (2) this phenotype most nearly resembles that of cells of the monocyte/macrophage series, thus suggesting that DRC are related to these cell lineages, and (3) DRC are multinucleated giant cells.

A cytotoxic monoclonal antibody specific for the private alloantigenic determinant of the HLA-B 13 molecule

A murine monoclonal antibody (TU 110) prepared against blast cells of a patient with acute "undifferentiated" leukemia was tested in the microcytotoxicity assay on peripheral blood lymphocytes of 122 normal Caucasian donors. The TU 110 reactivity was found to show a correlation coefficient of 1.0 in population analysis for the presence of the HLA-B locus specificity B 13 as defined by alloantisera. Family segregation studies confirmed MHC linked inheritance of the TU 110 antigenic determinant strictly on HLA-B 13 positive haplotypes. As the first monoclonal reagent against the private specificity of this HLA-B locus antigen, TU 110 provides the possibility to study the structural relationships of sub- and supertypic determinants on this allotype and may help to correlate antigenic domains of HLA-B 13 with definable functional properties.

[Properties of Hodgkin cell lines. Possible significance for pathophysiology and clinical medicine]

In the last three years, five permanently in-vitro growing cell cultures with malignant properties were established from tumour material of patients with histologically confirmed Hodgkin's disease. Four cell lines have been maintained in culture. L 428 had identical characteristics in every respect with Hodgkin and Sternberg-Reed cells, tested in-vivo on biopsy tissue. The other lines--L 538, L 540 and L 591 - had certain characteristics of Hodgkin and Sternberg-Reed cells with a number of markers, but were not fully congruent. All lines reacted with a heterologous antiserum against L 428, which selectively cross-reacted with Hodgkin and Sternberg-Reed cells in fresh biopsies. Two sublines, L 428 KS and L 428 KSA, were established from L 428 by modifying the culture medium. Tests on L 428 KS cells with conventional methods and with monoclonal antibodies demonstrated that this line carried antigens of myeloid cells; however, it could not be definitely placed into any haematopoetic line. Conditioned medium of L 428 and its sublines showed CSF activity (colony-stimulating factor) and suppression of cell-mediated cytolysis.

Quantitative and qualitative differences in the distribution of HLA class I antigenic determinants in the human thymic compartments

The topographical distribution of HLA class I antigens has been investigated by the immunoperoxidase technique on normal frozen thymic tissue sections with a panel of mono- and polymorphic monoclonal anti-HLA antibodies. HLA class I framework determinants detected by the monoclonal antibody W6/32.HL were present on 80-90% of cortical thymocytes, as well as on all cortical epithelial and medullary cells. However the staining intensity of cortical thymocytes with this reagent was about threefold weaker than that of the medullary thymocytes. Labelling patterns of selected monoclonal antibodies against matching HLA-A/B allospecificities revealed striking variations in the quantitative expression of certain HLA-A vs. HLA-B locus alloantigenic determinants on cortical thymocytes compared to a consistent staining on almost all medullary cells.

Hodgkin's cell lines: characteristics and possible pathogenetic implications

In the last four years we established five long term cultures from tumor material of Hodgkin's disease. The in vitro cells have malignant characteristics and represent the in vivo H- and SR-cells. Common immunological, functional and morphological assays did not characterize the in vitro cells to be a known cell type of lymphoid, myeloid or monocytoid tissue. The in vitro Hodgkin cells are biologically active by producing factors involved in regulation and promotion of immunological response and granulopoiesis. The relevance of the findings for pathogenesis and clinical appearance of Hodgkin's disease is discussed.

A cytotoxic monoclonal IgM antibody (Tü 101) directed against an antigenic determinant shared between the HLA-A allospecificities A2 and A28

A complement-fixing murine monoclonal IgM antibody (TU 101) strictly directed against a supertypic determinant present on the HLA-A locus antigens A2 and A28 was defined from a fusion experiment employing T cell blasts as immunizing cells. The specificity of this antibody was established in the microcytotoxicity assay on 91 normal Caucasian blood donors, as well as in the SpA-Ig assay on a panel of lympho- and hematopoietic cell lines. TU 101 segregates only with its defined HLA allotypes in families. This reagent may be of particular value as a probe for analyzing a molecular relationship of different antigenic determinants on the HLA-A2 and A28 specificities in comparison with two recently defined anti-HLA-A2/A28 monoclonal antibodies and may help to characterize structural variations of these HLA-molecules on a serological and immunochemical basis.