bluuebunny/crossref_metadata_2025 huggingface dataset:
Lysis of tumor biopsy cells by autologous T lymphocytes activated in mixed cultures and propagated with T cell growth factor.
Authors: Vánky F , Gorsky T , Gorsky Y , Masucci M G , Klein E
Published: June 2004

Blood lymphocytes from tumor patients were cocultivated with allogeneic lymphocytes (MLC) or autologous tumor cells (ATS), and their cytotoxicity was characterized. The main objective of the study was the lysis of autologous tumor biopsy cells by such effectors. Lymphocytes of patients activated in MLC lysed allogeneic third-party cells and in some cases also lysed autologous tumor cells. Allogeneic but not autologous PHA blasts were also damaged by these effectors. The cytotoxic potential of MLC-activated lymphocytes from healthy donors was similar; allogeneic tumors and phytohemagglutinin (PHA) blasts but not autologous PHA blasts were lysed. The cytotoxicity of lymphocytes activated in ATS were specific for the stimulator because they acted only on the autologous tumor cells. Allogeneic tumors and autologous and allogeneic PHA blasts were not lysed. The pattern of cytotoxicity with regard to this target panel was maintained when the MLC or ATS cultures were further propagated with TCGF. Results obtained in cold target competition assays suggested (a) activated lymphocyte lyse the third party tumor targets because of alloantigen recognition; (b) in MLC several different sets of alloreactive cytotoxic lymphocytes are present simultaneously; and (c) the alloreactive cells are different than those that act on the autologous tumor cells. Thus, the lysis of allogeneic tumor cells by lymphocytes of the patient is not due to recognition of cross-reacting tumor-related antigens, and the autotumor cytotoxicity of the patients' MLC-activated lymphocytes if performed by specifically reacting cells.
Participation of the major histocompatibility complex in antibody recognition of viral antigens expressed on infected cells.
Authors: Wylie D E , Sherman L A , Klinman N R
Published: June 2004

The capacity of the antibody repertoire to recognize complex antigens on viral-infected cells was investigated at the level of monoclonal B cell responses. A majority of primary B cells responsive to PR8(H1N1)-infected H-2 syngeneic cells produced antibody that bound viral determinants only in the context of infected cells and not the isolated virion. An examination of the fine specificity of such antibodies revealed that most could be distinguished by a panel of cells infected with closely related heterologous H1 influenza strains. Indeed, most antibodies bound hemagglutinin determinants of PR8 exclusively, and few were broadly cross-reactive. An examination of the same antibodies for their recognition of cell surface antigens revealed that the majority recognized MHC-encoded antigenic determinants. Thus, most BALB.K (H-2k) primary B cells responsive to PR8-L919 (H-2k) cells produced monoclonal antibodies that bound PR8-antigens only in the context of H-2Dk-infected cells. Most C57BL/10 (H-2b) B cells responsive to PR8-EL4 (H-2b) cells produced monoclonal antibodies that bound PR8 antigens only in the context of H-2Kb-infected cells. These latter antibodies were further shown to recognize that H-2Kb molecule by virtue of their capacity to be discriminated by a panel of PR8-infected H-2Kb mutant cells. These findings demonstrate that much of the antibody repertoire is capable of highly specific complex recognition of viral antigenic determinants in the context of the appropriate MHC alloantigen.
Resting macrophages produce distinct metabolites from exogenous arachidonic acid
Authors: Scott WA , Pawlowski NA , Andreach M , Cohn ZA
Published: June 2004

Resident mouse peritoneal macrophages rapidly metabolize free arachidonic acid (20:4) in the absence of a discernible trigger. After a 20-min incubation in serumless medium, one-third of the fatty acid was found esterified in cell phospholipid and two-thirds was metabolized to oxygenated products which were recovered in the culture medium.

The 20:4 oxygenated metabolites were identified by reverse-phase high performance liquid chromatography as hydroxyeicosatetraenoic acids (HETEs) and 6-keto prostaglandin F(1a) (6-ketoPGF(1a)), the stable form of prostacyclin, together with prostaglandin E(2) (PGE(2)) in proportions of 67:24:9. Inhibitor studies using indomethacin, nordihydroguaiaretic acid, and 5,8,11,14-eicosatetraenoic acid confirmed these metabolites to be lipoxygenase and cyclo-oxygenase products. The proportion of products differs considerably from those generated from phospholipid 20:4 in response to a phagocytic stimulus (HETEs:6-ketoPGF(1a):PGE(2):leukotriene C, 15:25:40: 15-20). Cornyebacterium parvum-elicited macrophages incorporated a higher percentage (70 percent) of exogenously supplied 20:4 and converted less than 20 percent of the fatty acid to oxygenated metabolites. Cyclo-oxygenase products (PGE(2), PGF(2a), TXB(2), and 6-ketoPGF(1a)) represented the major 20:4 metabolites (74 percent) synthesized by these activated macrophages.

Esterification of 20:4 into cell phospholipids appeared not to be an initial obligatory step for synthesis of 20:4 oxygenated products by this route. To the contrary, incorporation of 20:4 into cell lipids and metabolism via the cyclo-oxygenase and lipoxygenase pathways represent distinct metabolic fates of exogenously supplied 20:4.

These observations establish that resting macrophages contain high levels of cyclo-oxygenase and lipoxygenase activity and suggest macrophages can synthesize lipid mediators of inflammation in the absence of an inflammatory stimulus.
Mechanisms of syngeneic tumor rejection. Susceptibility of host-selected progressor variants to various immunological effector cells.
Authors: Urban J L , Burton R C , Holland J M , Kripke M L , Schreiber H
Published: June 2004

The ultraviolet radiation-induced fibrosarcoma 1591 generally is rejected by normal syngeneic mice and only rarely exhibits progressive growth. We isolated five of these rare progressor tumors from normal animals to determine the selective pressures that had been exerted upon the parental tumor by normal immunocompetent hosts. We found that the variant tumor cell lines could neither induce nor be killed by tumor-specific lymphocytes, suggesting that selection had been exerted against tumor cells expressing the tumor-specific antigen. In contrast, no selection against natural killer cell activity or against nonspecific T cell-mediated immunity seems to have occurred because progressor tumor cells were highly sensitive to these types of effector cells and in fact induced these effector cells more effectively than did the parental tumor. Nude mice were found to be as capable as normal mice in generating natural killer activity in response to a challenge with progressor tumor cells, but they were unable to mount a nonspecific T lymphocyte response. This may account for the fact that the progressor tumors grew at a significantly faster rate in nude animals than in normal mice. Thus, our study shows that in this tumor system nonspecific T cell-mediated immunity may play a role in retarding tumor growth, but the absolute resistance of normal animals to progressive tumor growth critically depends upon the presence of T cell-mediated tumor-specific immunity. Furthermore, neither NK cells nor nonspecific cytotoxic T lymphocytes appear to play a role in immunoselection against this tumor in normal immunocompetent hosts.
Concomitant induction of the cell surface expression of Ia determinants and accessory cell function by a murine macrophage tumor cell line.
Authors: Walker E B , Lanier L L , Warner N L
Published: June 2004

This study demonstrates that an uncharacterized soluble factor produced in concanavalin A-induced rat spleen cell suspensions has the capacity to induce the increased expression of cell surface H-2K and H-2D molecules and the expression of I-region gene products on murine monocyte-macrophage lineage tumors that are not Ia positive in the absence of the factor. In parallel with induction of serologically defined Ia specificities, Ia-induced WEHI-3 macrophage tumor cells are capable of providing accessory cell function in stimulating IL-2 production by T-T hybridomas that are activated in a major histocompatibility complex-restricted, antigen-dependent fashion. The uninduced Ia-negative WEHI-3 tumor cells do not trigger a comparable response in this assay system.
Immunoregulation of murine myeloma in vitro. II. Suppression of MOPC-315 immunoglobulin secretion and synthesis by idiotype-specific suppressor T cells.
Authors: Milburn G L , Lynch R G
Published: June 2004

In previous studies, BALB/c mice immunized with trinitrophenyl-specific IgA protein (M315) produced by MOPC-315 developed idiotype (Id315)-specific T cells that suppressed M315 secretion in vivo. In the present in vitro studies, we show that inhibition of M315 secretion is mediated by a theta,Lyt-1-2+ cell that expresses a surface membrane receptor for Id315. The suppressor signal is a diffusable product that acts directly on M315-secreting myeloma cells. Inhibition of M315 secretion is T cell dose-dependent, Id315-specific, reversible, and occurs without any effect on MOPC-315 growth, viability, or surface membrane expression of M315. Inhibition of M315 secretion results from a selective inhibition of M315 synthesis in the myeloma cell. These studies provide new insight into the mechanisms of direct B cell regulation by idiotype-specific T cells.
T cell regulation of immunoglobulin class expression in the antibody response to trinitrophenyl-ficoll. Evidence for T cell enhancement of the immunoglobulin class switch.
Authors: Mongini P K , Paul W E , Metcalf E S
Published: June 2004

In the absence of T cells, B cells were found to respond to the type 2 T-independent (TI-2) antigen, trinitrophenyl (TNP)-Ficoll, with a characteristic hierarchy of IgM and IgG subclass Ab production which directly correlated with 5' to 3' Igh-C gene order, i.e., IgM greater tha IgG3 greater than IgG1 greater than IgG2b greater than IgG2a. This was evident when immune serum Ab titers were analyzed, when in vitro secretion of antibody from immune cells was measured and when TNP-Ficoll-stimulated clones in a splenic focus assay were analyzed for isotype production. T cells were found to cause a preferential relative increase in the amount of IgG2a antibody produced to TNP-Ficoll. The T cell responsible was present in anti-IgM neonatally suppressed mice and was needed early in the response, i.e., on the day of immunization or earlier. T cells were found to increase the frequency of TNP-Ficoll-responsive B cell clones that produced IgG2a in the splenic focus assay. The great majority of these IgG2a-positive clones also produced IgM and all or nearly all of the IgG isotypes whose genes are encoded 5' to the Igh-gamma 2a gene. The data are discussed in terms to T cell enhancement of IgG2a Ab synthesis being mediated through T cell enhancement of the Igh-C gene switching mechanism within TNP-Ficoll-responsive B cell clones. Thus, isotypes encoded by genes on the 3' end of the Igh-gamma gene complex, which in the absence of T cells have a low probability of being switched to, are the most influenced by T cell help.
Hybridoma antibodies against protective and nonprotective antigenic determinants of a structurally defined polypeptide fragment of streptococcal M protein.
Authors: Hasty D L , Beachey E H , Simpson W A , Dale J B
Published: June 2004

Hybridoma technology was used to produce a set of monoclonal antibodies against a purified polypeptide fragment of type 24 streptococcal M protein to delineate the protective determinants of M protein exposed on the surface of the virulent streptococci. Several hybridoma antibodies were found to be opsonic against the homologous type streptococci. At least two of these antibodies (IIC3.7 and IIC4.6) protected mice against challenge infections with the homologous, but not a heterologous, serotype of bacteria. One of the hybridoma antibodies that reacted in high dilution (1:204,800) with the isolated M protein failed to react with the M protein on the surface of type 24 streptococci, and thus did not opsonize the homologous organisms or protect mice against challenge infections. Because hybridoma antibodies are directed against a single distinct immunodeterminant, these results indicate that protective immunity may be directed at any one of several distinct antigenic determinants of M protein exposed on the surface of virulent group A streptococci.
Chromosomal location of a human alpha interferon gene family.
Authors: Slate D L , D'Eustachio P , Pravtcheva D , Cunningham A C , Nagata S , Weissmann C , Ruddle F H
Published: June 2004

To determine the chromosomal location of the human alpha interferon genes, we scored a series of human/rodent somatic cell hybrids for the presence of DNA sequences hybridizing to an alpha 1 interferon DNA probe. The presence of human chromosome 9 in a hybrid correlated with the presence of a family of alpha interferon genes.
B lymphocyte immune response gene phenotype is genetically determined.
Authors: Tse H Y , Mond J J , Longo D L
Published: June 2004

We examined the effects of the developmental milieu on the capacity of B cells to undergo immune response gene-controlled, T cell-dependent polyclonal proliferation. Although I-Aq poly(Glu60 Ala30 Tyr10)n (GAT)-nonresponder T cells developing in a responder environment become phenotypic GAT-responders, I-Aq B cells remain unresponsive to GAT, even after maturation in a GAT-responder animal. Conversely, (B10.A x B10.Q)F1 ([GAT responder x GAT nonresponder]F1) T cells developing in a B10.Q GAT nonresponder host fail to respond to GAT, but F1 B cells from the same F1 leads to parent chimeras make excellent proliferative responses in the presence of GAT and responder T cells. Thus, by this assay, B cell immune response gene function is genetically determined and is not affected by the developmental milieu.
Antigen-specific T lymphocyte clones. III. Papain splits purified T suppressor molecules into two functional domains.
Authors: Fresno M , McVay-Boudreau L , Cantor H
Published: June 2004

Purified molecules (70,000 mol wt) from a T-suppressor (Ts) clone bind to sheep erythrocyte glycophorin and specifically suppress the response to this antigen. Papain splits purified 70,000-mol wt Ts molecules into two peptides: mol wt 45,000 and 24,000. The 45,000-mol wt peptide nonspecifically suppresses antibody response to several antigens and lacks antigen-binding activity. The 24,000-mol wt peptide does not suppress but retains antigen-binding activity. The results indicate that papain splits the Ts molecule into a "constant" region responsible for function and a "variable" region responsible for antigen-binding. Since binding of the 70,000-mol wt molecule to antigen also results in release of the 45,000 mol wt subunit, this cleavage may allow Ts molecules specific for one determinant to suppress immunity to complex foreign proteins.
Evidence that Lyb-2 is critical to specific activation of B cells before they become responsive to T cell and other signals.
Authors: Yakura H , Shen F W , Bourcet E , Boyse E A
Published: June 2004

The generation of plaque-forming cells (PFC) to T-dependent antigen, but not to T-independent antigen, is reduced in vitro by Lyb-2 antibody. Monoclonal Lyb-2 antibody, added to Mishell-Dutton cultures within the first 2 d, but not later, greatly reduces the generation of alpha-sheep erythrocyte (SRBC) PFC from T-depleted spleen cells whether help is provided in the form of intact T cells or as soluble factors contained in mixed lymphocyte culture (MLC) supernatants. Generation of alpha-SRBC PFC from purified B cells, assisted by soluble factors in MLC and macrophage (P388D.1 cell) supernatants, is similarly reduced by Lyb-2 antibody. The initial 2-d period, during which cultures are diminishingly sensitive to reduction of PFC generation by Lyb-2 antibody, is not affected by the time at which such soluble factors are added. Thus, Lyb-2 cell surface molecules evidently do not function as receptors for these differentiative signals. Reduction of PFC generation by Lyb-2 antibody is antigen dependent in the sense that reduction of the PFC response to one antigen (SRBC) does not affect subsequent generation of PFC to a second antigen (horse erythrocytes) from the same cell population. These findings accord with the view that the Lyb-2 molecule participates in a B cell differentiative phase, probably proliferative, which begins with binding of antigen and precedes the phase in which B cells become fully receptive to signals from T and other cells.
HLA-Dw2: a genetic marker for human immune response to short ragweed pollen allergen Ra5. I. Response resulting primarily from natural antigenic exposure.
Authors: Marsh D G , Hsu S H , Roebber M , Ehrlich-Kautzky E , Freidhoff L R , Meyers D A , Pollard M K , Bias W B
Published: June 2004

Ultra-pure short ragweed pollen allergen Ra5 (5,000 mol wt) was used to investigate the relationship between human leukocyte antigen (HLA) type and IgE and IgG antibody (Ab) responses to Ra5 in two groups of Caucasian subjects, totaling 447 people. Using highly sensitive radioimmunoassay procedures to measure serum IgE and IgG Ab, qualitative responses to Ra5 in both groups were found to be strongly associated with HLA-Dw2 (P less than 0.0001). For example, 95% of 38 people with IgE Ab vs. 22% of 139 ragweed-allergic persons having no detectable IgE Ab to Ra5 were Dw2+. Quantitative log [IgE Ab] and log[IgG Ab] responses to Ra5 were highly correlated with Dw2 (P = 10(-5) to 10(-14)) in four separate multiple regression analyses, examining the relationship between HLA type (and other variables) and Ab levels in the two study groups. Further studies showed that the primary association of Ra5 response was with Dw2 rather than DR2 and that various combinations of A3, B7, and Dw2 were less strongly associated than Dw2 alone.
Murine lymphoid procoagulant activity induced by bacterial lipopolysaccharide and immune complexes is a monocyte prothrombinase
Authors: Schwartz BS , Levy GA , Fair DS , Edgington TS
Published: June 2004

Murine lymphoid cells respond rapidly to bacterial lipopolysaccharide or antigen-antibody complexes to initiate or accelerate the blood coagulation pathways. The monocyte or macrophage has been identified as the cellular source, although lymphocyte collaboration is required for the rapid induction of the procoagulant response. This procoagulant activity is identified in the present study as a direct prothrombin activator, i.e., a prothrombinase. Studies with plasmas deficient in single coagulation factors demonstrate that the induced murine procoagulant activity effector molecule does not require factors XII, VIII, VII, X, or V, but does require prothrombin to transform fibrinogen to fibrin. This enzyme(s) produces limited proteolysis of prothrombin to yield thrombin or thrombinlike products that are functionally capable of converting fibrinogen to fibrin. The prothrombinase is undetectable in freshly isolated Murine lymphoid cells respond rapidly to bacterial lipopolysaccharide or antigen-antibody complexes to initiate or accelerate the blood coagulation pathways. The monocyte or macrophage has been identified as the cellular source, although lymphocyte collaboration is required for the rapid induction of the procoagulant response. This procoagulant activity is identified in the present study as a direct prothrombin activator, i.e., a prothrombinase. Studies with plasmas deficient in single coagulation factors demonstrate that the induced murine procoagulant activity effector molecule does not require factors XII, VIII, VII, X, or V, but does require prothrombin to transform fibrinogen to fibrin. This enzyme(s) produces limited proteolysis of prothrombin to yield thrombin or thrombinlike products that are functionally capable of converting fibrinogen to fibrin. The prothrombinase is undetectable in freshly isolated
Human B cell differentiation. II. Pokeweed mitogen-responsive B cells belong to a surface immunoglobulin D-negative subpopulation.
Authors: Kuritani T , Cooper M D
Published: June 2004

Surface immunoglobulin D (IgD)-positive lymphocytes precoated with monoclonal anti-delta antibody were selectively removed from blood mononuclear cell preparations by "panning" and by fluorescence-activated cell sorter. The depletion of sIgD+ cells did not significantly affect plasma cell responses to pokeweed mitogen PWM). PWM-responsive B cells lacking sIgD and mouse erythrocyte receptors preferentially sedimented in lower density fractions of a discontinuous Percoll gradient, and sIgD-negative B cells were found to have a larger mean diameter than IgD-positive cells. We conclude that PWM-responsive B cells represent a distinct subpopulation of relatively large cells that have ceased to express receptors for mouse erythrocytes and surface IgD.
Major histocompatibility complex-restricted H-Y-specific antibodies and cytotoxic T lymphocytes may recognize different self determinants.
Authors: Goulmy E , van Leeuwen A , Blokland E , van Rood J J , Biddison W E
Published: June 2004

Previous studies have shown that influenza virus-immune cytotoxic T lymphocytes can recognize virus in conjunction with self HLA-A2 antigens. Nevertheless, the virus-infected target cells from one HLA-A2-positive male donor (designated M7) could not be lysed by the virus-immune cytotoxic lymphocytes from any HLA-A2-matched unrelated donors. Although extensive serological analyses showed no difference between the HLA-A2 antigens of donor M7 and other HLA-A2-positive donors, isoelectric focusing of the HLA-A2 molecule from donor M7 revealed a clear difference in the heavy polypeptide chains when compared with the HLA-A2 molecules of other donors. The present study demonstrates that the HLA-A2-restricted anti-H-Y cytotoxic T lymphocytes obtained from a female aplastic anaemia patient fail to lyse the male M7 target cells, whereas the HLA-A2-restricted anti-H-Y antibodies from the same patient react with the cells of donor M7. These results suggest that: (a) HLA-A2-restricted anti-H-Y antibodies can recognize self determinants on the HLA-A2 molecule that are distinct from those that are recognized by HLA-A2-restricted anti-H-Y cytotoxic T cells; and (b) HLA-restricted T and B cells may use different receptor repertoires for the recognition of foreign antigens such as H-Y.
Formation of Charcot-Leyden crystals by human basophils.
Authors: Ackerman S J , Weil G J , Gleich G J
Published: June 2004

Charcot-Leyden crystals (CLC) are currently believed to be unique to the eosinophil and a hallmark of active eosinophilic inflammation or proliferation. The distinctiveness of the CLC to the eosinophil was questioned in 1965 by Archer and Blackwood (9), but their demonstration of CLC formation in basophils was ignored and later dismissed (1) as being the result of eosinophil contamination of basophil-enriched cell suspensions. We reexamined this question and showed that basophils obtained from the peripheral blood of normal individuals form CLC and that basophils contain a protein that is immunochemically indistinguishable from eosinophil CLC protein. These conclusions are based upon the findings that (a) crystal formation in basophils was demonstrated by specific histochemical staining of crystal-containing cells in highly enriched basophil suspensions prepared by fluorescence-activated cell sorter (FACS) purification of surface IgE-positive cells, (b) that enrichment for surface IgE-positive cells (primarily basophils) by the FACS also enriched for cells staining positively by immunofluorescence for eosinophil CLC protein, and (c) that CLC protein was measured by radioimmunoassay in cell extracts prepared from purified basophil suspensions containing 97-99% basophils and absolutely no contaminating eosinophils. These basophil extracts contained a protein immunochemically indistinguishable from eosinophil CLC protein. Based upon these findings, the CLC or the protein comprising the crystal (lysophospholipase) can no longer be considered as distinctive to the eosinophil. We must now consider the possibility that the presence of CLC in tissues, sputum, or stool may also represent basophil involvement in disease processes.
Tolerance of thymocytes to allogeneic i region determinants encountered prethymically. Evidence for expression of anti-Ia receptors by T cell precursors before their entry into the thymus
Authors: Bradley SM , Morrissey PJ , Sharrow SO , Singer A
Published: June 2004

The present study has assessed whether precursor T cells express receptors specific for the recognition of allogeneic I region-encoded determinants before their entry into the thymus. Because the ability of thymocytes to proliferate in response to allogeneic stimulator cells was shown to primarily result from the recognition of allogeneic I region determinants, thymocytes must already express anti-Ia receptors. In contrast, the expression of anti- Ia receptors by functionally immature thymocyte precursors could not be directly assessed by mixed lymphocyte reaction reactivity. However, expression of anti-Ia receptors by thymocyte precursors could be assessed by their ability to be specifically tolerized by the allogeneic Ia determinants that they encountered during their differentiation.

To determine whether T cell precursors could specifically recognize and be tolerized to allogeneic Ia determinants expressed prethymically, thymus- engrafted radiation bone marrow chimeras were constructed [A {arrow} A x B (Tx + A Thy)] such that strain A T cells would be differentiating within a syngeneic strain A thymus but would have been previously exposed to the allogeneic strain B Ia determinants of the irradiated A x B host. The strain A thymocytes from these experimental animals were indeed tolerant to the extrathymic allogeneic strain B Ia determinants expressed by the irradiated host. Such tolerance was not mediated by detectable suppression and was not explained by the presence intrathymically of extrathymic allogeneic Ia determinants. Thus, these results suggest that T cell precursors can be specifically tolerized entry into the thymus. In addition, the failure to detect the generation of thymocytes with specificity for the allogeneic Ia determinants of the irradiated host, which were not deleted prethymically, argues that novel anti-allo Ia receptor specificities are not generated intrathymically.
Streptococcal cell walls and synovial cell activation. Stimulation of synovial fibroblast plasminogen activator activity by monocytes treated with group A streptococcal cell wall sonicates and muramyl dipeptide.
Authors: Hamilton J A , Zabriskie J B , Lachman L B , Chen Y S
Published: June 2004

Group A streptococcal peptidoglycan has previously been shown to be arthritogenic in rats and has been implicated as a structure present in a class of possible etiologic agents for rheumatoid arthritis. The present study reports that conditioned medium from human monocytes, after interaction with cell wall sonicates of four group A streptococcal strains, stimulates the plasminogen activator (PA) activity of nonrheumatoid synovial fibroblasts. Low concentrations of N-acetylmuramyl-L-alanyl-D isoglutamine (muramyl dipeptide) can also generate this synovial activator (SA) activity from human monocytes. Preliminary biochemical data suggest that the SA activity is distinct from interferon-gamma, interleukin 1, and interleukin 2. These results indicate that agents that are arthritogenic in rats can modulate human synovial fibroblast functions via monocytes. The findings are proposed to have possible significance for an understanding of the cellular interactions involved in the formation and function of the rheumatoid pannus, because PA has been invoked as possibly being generally important for the processes of cell migration, tissue remodeling, and inflammation.
Germ cell-induced immune suppression in mice. Effect of inoculation of syngeneic spermatozoa on cell-mediated immune responses.
Authors: Hurtenbach U , Shearer G M
Published: June 2004

Spleen cells from mice injected intravenously with syngeneic male germ cells exhibited reduced immune functions as determined by natural killer cell activity, mixed lymphocyte reactivity and cytotoxic lymphocyte (CTL) function. The decrease in CTL responses to trinitrophenyl-modified self (TNP-self) was detected as early as 4 d after sperm injection and was observed to H-2 alloantigens 3 wk after injection. Radiosensitive suppressor T cells were found to suppress the CTL response to TNP-self. Suppression lasted for a period of at least 7 wk after a single inoculation of the germ cells. Some variability in immune suppression capability was observed using different preparations of germ cells which are not yet completely understood. Sperm were more effective in inducing suppression than testicular cells derived from the seminiferous tubules. Furthermore, sperm from older animals were more effective than those from younger mice. These findings are discussed with respect to possible regulatory influences of germ cells on the immune system when the blood-testes barrier is broken.
Epitope-specific regulation. I. Carrier-specific induction of suppression for IgG anti-hapten antibody responses
Authors: Herzenberg LA , Tokuhisa T
Published: June 2004

The epitope-specific regulatory system selectively controls IgG antibody production to the individual (haptenic) determinants on a complex antigen. This system can be specifically induced to suppress primary and secondary IgG antibody responses to dinitrophenyl hapten (DNP) without interfering with antibody responses to epitopes on the carrier molecule on which the DNP is presented. Furthermore, once induced, it will specifically suppress responses to DNP presented on unrelated carrier molecules. Results summarized here obtained using widely different immunization conditions, and a variety of haptens and carrier molecules indicate that this regulatory system controls antibody production in most T-dependent antibody responses.

Carrier-specific suppressor T cells (CTs) that arise shortly after priming with a carrier molecule such as keyhole limpet hemocyaninin (KLH) induce the epitope-specific system to suppress in situ and adoptive antibody responses to epitopes (e.g., DNP) presented subsequently on the priming carrier. These well-known regulatory T cells are commonly believed to regulate antibody production by interfering with carrier-specific help; however, by repeating the original CTs transfer experiments with additional controls that define the specificity of the mechanism mediating suppression in CTs recipients, we show that KLH-specific CTs regulate responses by inducing typical isotope- specific suppression for anti-DNP responses when the recipients are immunized with DNP-KLH. Thus, whether KLH-primed animals are immunized directly with DNP-KLH (KLH/DNP-KLH immunization sequence) or whether T cells from these animals are challenged with DNP-KLH in (nonirradiated)recipients, anti-DNP responses are persistently suppressed while anti-carrier responses proceed normally.

The aqueous KLH-priming protocols usually used to generate CTs are marginally more effective in priming for in situ suppression-induction than the alum KLH-priming protocols commonly used to generate KLH-specific helper T cells and used here in KLH/DNP-KLH immunizations. Thus, studies presented show that priming with an antigenic (carrier) molecule simultaneously prepares the animal for the production of typical secondary (anamnestic) antibody responses to epitopes on the priming antigen and for the induction of epitope-specific suppression for antibody production to determinants presented subsequently on the same antigenic molecule. We discuss the mechanism(s) responsible for this duality and its significance for antibody responses in an accompanying publication that describes the bistable regulatory capabilities of the epitope-specific system.
Hapten-specific responses to the phenyltrimethylamino hapten. III. Mice whose delayed-type hypersensitivity responses cannot be abrogated by the presence of anti-idiotypic suppressor T cells lack a critical modulatory T cell function.
Authors: Jayaraman S , Bellone C J
Published: June 2004

A single intraperitoneal injection of the monovalent synthetic antigen, tyrosinated trimethylaminoaniline [tyr(TMA)] in Freund's complete adjuvant induces an antiidiotypic second-order T suppressor (Ts2) cell population 6 wk later. This population was able to suppress TMA-specific delayed-type hypersensitivity (DTH) responses when adoptively transferred into normal syngeneic recipients. However, they failed to function intrinsically. The inability of the Ts2 to function intrinsically was not caused by compensating idiotype-negative T cells that mediate DTH. Rather, this paradoxical observation was found to be caused by the absence or loss of function of a critical modulatory T cell population in the suppressor cell-bearing mice. This cell is functionally active in normal mice immunized for DTH responses and is sensitive to cyclophosphamide treatment. In addition, this cell type bears idiotype on its surface and is Thy-1+ and Lyt-1-,2+. It was demonstrated that by adoptively transferring the activated modulatory T cells from normal mice into tyr(TMA)-immune recipients, it was possible to observe suppressor cell function intrinsically. The potential importance of modulatory T cell function in the regulation of antibody and DTH responses is discussed.
Establishment of long-term monocyte suspension cultures from normal human peripheral blood.
Authors: Salahuddin S Z , Markham P D , Gallo R C
Published: June 2004

The long-term suspension growth of normal, immature myeloid cells from fresh human cord blood was recently reported and required cells separated on supplemented discontinuous Percoll gradients, growth in media containing hydrocortisone and vitamins D3, and gentle, continuous agitation (13). When normal adult bone marrow (six donors) or blood from Epstein-Barr virus (EBV)-seropositive donors (nine donors) was used as a source of fresh human leukocytes, only short-term proliferation of myeloid cells was achieved with the same techniques. However, when leukocytes prepared from EBV seronegative normal adult peripheral blood were used, pure populations of monocytes and macrophages that replicate slowly in liquid suspension culture for greater than 5 mo were repeatedly obtained from three independent donors. These cultures consists of several morphologically distinguishable monocytic cell types, including an approximately 20% adherent macrophage population. The monocytic nature of these cultures was confirmed by cytochemical, immunological, and functional criteria. These monocytes retain a normal chromosome pattern and can be induced to differentiate to phagocytic cells by treatment with tetradecanylphorbal acetate. Eventually, the cultures terminate as nonreplicating mature macrophages. These liquid suspension cultures should be a valuable resource for morphological, biochemical, and functional studies of developing monocyte-macrophages and their interaction with other cell types in normal and various pathological situations.
Low dose radiosensitivity of alloimmune cytotoxic T cells.
Authors: Spellman C , Anderson R E
Published: June 2004

Low dose radiosensitivity of in vitro generated alloimmune murine cytotoxic T lymphocytes (CTL) was studied. It appears that a subset of CTL exists that can be killed with 10-25 rad of x rays. These radiosensitive CTL are Lyt-1,2+ T lymphocytes. Analyses of cytotoxicity by chromium release assays indicate that the radiosensitive CTL are present in responder spleen cell cultures from all strains of mice tested. The generation of these effector cells is most pronounced in animals of the C57BL background. The mechanism of low dose radiosensitivity appears to be interphase death.
T cells from fully H-2 allogeneic (A replaced by B) radiation bone marrow chimeras are functionally competent and host restricted but are alloreactive against hybrid Ia determinants expressed on (A x B)F1 cells.
Authors: Kruisbeek A M , Hathcock K S , Hodes R J , Singer A
Published: June 2004

In this communication it is demonstrated that T cells from fully allogeneic A replaced by B radiation bone marrow chimeras are alloreactive against the hybrid Ia molecules expressed on the surface of heterozygous A X B cells. These results suggested that previous failures to generate cytotoxic T lymphocyte (CTL) responses from fully allogeneic chimeras by sensitizing the chimeric T cells to antigen in an (A X B)F1-priming environment might have been confounded by an ongoing alloreaction against determinants created by hybrid Ia molecules expressed on F1 cells. Consequently, the ability to generate CTL responses from fully allogeneic chimeras was re-examined by sensitizing the chimeric T cells to antigen presented by homozygous rather that F1 stimulator cells. It was found that T cells of donor bone marrow origin that mediate cytotoxic responses to trinitrophenyl-modified self determinants do differentiate into functional competence in an H-2-incompatible host environment and are restricted to the host H-2 haplotype.
Mitogen-reactive B cell subpopulations selectively express different sets of V regions.
Authors: Primi D , Mami F , Le Guern C , Cazenave P A
Published: June 2004

The experiments presented here were designed to investigate whether the idiotypic repertoire is equally distributed among B cells subpopulations as defined by mitogen reactivity. To this end we used lipopolysaccharides (LPS) and Nocardia delipidated cell mitogens (NDCM), which are two mitogens that have been described to act on different B cell subsets. The repertoire can be defined in quantitative terms as the frequency of B cells that are precursors for clones secreting immunoglobulin with a given specificity or with a determinate idiotype. We determined, therefore, the absolute frequency of LPS- and NDCM-sensitive B lymphocytes secreting immunoglobulin molecules that bear three idiotopes originally found on a monoclonal anti-beta galactosidase antibody. Because the frequencies of B cells carrying one of these idiotypes are dramatically different in the LPS- and NDCM-sensitive B cells subsets, we conclude that the idiotypic repertoire is not randomly distributed among mitogen-reactive B cell subpopulations.
Cytotoxic T cell response to minor histocompatibility antigens: apparent lack of H-2 restriction in killers stimulated by membrane fragments.
Authors: Pilarski L M , Vergidis D
Published: June 2004

The secondary cytotoxic T cell response of BALB/c to B10.D2 or DBA/2 minor histocompatibility antigens in vitro requires the participation of an adherent cell. Nylon wool-passed spleen cells were only able to respond to nonadherent intact stimulator cells, or to membrane fragments derived from those cells, if a syngeneic adherent cell were present in the cultures. When the H-2 restriction properties of cytotoxic cells generated in response to various types of stimulation were analyzed, it was found that responses to B10.D2 or DBA/2 intact cells were always H-2 restricted. Responses to syngeneic adherent cells presenting B10.D2 or DBA.2 freeze-thaw antigen were either entirely or predominantly lacking in H-2 restriction as defined by efficient competition by B10 (H-2b) cold target cells. These unrestricted killers appeared to recognize minor histocompatibility as an independent determinant rather than as an H-2d/minors moiety cross-reaction with H-2b, because they were not absorbed by BALB.B (H-2b) macrophage monolayers, but were absorbed by B10 monolayers. Similarly, B10 but not BALB.B cold targets were able to compete for the anti-B10.D2 killers. These experiments eliminate the possibility that the lack of restriction was due to an H-2b restricted receptor cross-reactive with H-2b. Possible models to explain these findings are discussed.
Immunologic studies on the influenza A virus nonstructural protein NS1.
Authors: Shaw M W , Lamon E W , Compans R W
Published: June 2004

We purified the major influenza virus nonstructural protein, designated NS1, from cytoplasmic inclusions that were solubilized and used to raise antisera in rabbits. One of the antisera was found to be specific for NS1 by complement fixation tests and analyses of immune precipitates. Antiserum to NS1 isolated from cells infected with A/WSN/33 virus specifically precipitated NS1 from extracts of cells infected with seven distinct isolates of influenza A virus representing five different antigenic subtypes. These included A/WSN/33, A/PR/8/34, A/FW/5/50, A/USSR/90/77, A/RI/5+/57, A/Victoria/3/75, and A/Swine /1977/31; however, NS1 from cells infected with B/Lee/40 virus was not precipitated. Radioimmunoassays using radioiodinated NS1 protein from A/WSN virus-infected cells and unlabeled cytoplasmic extracts of cells infected with various strains of influenza virus as competitors indicated significant antigenic cross-reactivities for the NS1 proteins of all influenza A viruses tested. The results suggest a gradual antigenic drift over the 45 yr separating the earliest and most recent virus isolates examined. Thus, compared with the virion neuraminidase and hemagglutinin antigens, NS1 appears to be highly conserved in different influenza A virus isolates.
Hapten-specific T cell lines mediating delayed hypersensitivity to contact-sensitizing agents.
Authors: Thomas W R , Mottram P L , Miller J F
Published: June 2004

Continuous cultures of T cells from the lymph nodes of mice sensitized to the contact sensitizers 4-ethoxymethylene-2-phenyl oxazolone or picryl chloride have been established. For continuous proliferation, the lines required specific antigen, syngeneic antigen-presenting cells, and growth factors from the supernatant of concanavalin-A-stimulated lymphoid cultures. Cells from the lines showed antigen specificity and major histocompatibility complex restriction in proliferation assays and in delayed hypersensitivity. They could mediate delayed hypersensitivity to the sensitizer presented as a reactive hapten or coupled to keyhold limpet hemocyanin.
T-T cell interactions during in vitro cytotoxic T lymphocyte responses. V. Precursor frequencies and specificity of alloreactive helper T cells.
Authors: Krönke M , Scheurich P , Pfizenmaier K , Röllinghoff M , Wagner H
Published: June 2004

We assessed the quantitative representation and specificity of alloreactive helper T lymphocytes (HTL) within murine spleen cells by three different limiting dilution systems. For the induction of primary cytolytic T lymphocyte (CTL) responses towards alloantigens, a Lyt-1+23- HTL precursor (HTLp) could be defined, which occurred at frequencies of 1/2.000-1/50,000, depending on the alloantigen in question. The HTLp limiting for interleukin-2 (Il-2) production also expressed the Lyt-1+ phenotype and occurred in similar frequencies. This cell type was concluded to be the limiting HTLp for the overall helper activity required for the induction of primary CTL responses. HTLp reactive to Mlsa -encoded antigens occurred at higher frequencies (1/500) than those reactive towards whole allogeneic H-2 haplotypes (1/4,000-1/7,000). Within the H-2 complex, I region-encoded alloantigens activated approximately 10 times more HTLp than did H-2K or H-2D regions. When alloreactive HTL were tested for antigen specificity at the clonal level, approximately 80% of the HTL clones proved to be specific to the alloantigen used for immunization, whereas approximately 20% reacted also towards third-party alloantigens. The data are discussed with respect to putative T-T interactions within the helper T cell population and the precision of alloantigen recognition by HTL.
Lymphocytic choriomeningitis virus killer T cells are lethal only in weakly disseminated murine infections.
Authors: Pfau C J , Valenti J K , Pevear D C , Hunt K D
Published: June 2004

Two types of lymphocytic choriomeningitis (LCM) viruses were studied which, upon intracerebral injection into adult C3H mice, provoked either (a) acute fatal central nervous system (CNS) disease or (b) life-long persistent infection. Both virus types, (a) aggressive and (b) docile, had been found to induce LCM-specific lymphocytes with comparable in vitro lytic activity (11). Because the requirement for T cells in the development of adult LCM disease has been extensively documented, we sought other reasons for the lack of acute disease in mice infected with docile virus. A striking correlation was found between the outcome of the infection and spread of virus to visceral organs. Adoptive transfer experiments showed that a 300-plaque forming unit inoculum of docile virus induced a population of T cells in donor mice fully capable of causing CNS disease in identically infected recipients. This disease causing ability was lost if the interaction was delayed beyond 3 d after infection of the recipients, but could be preserved by lowering the size of the viral inoculum in the recipients. Furthermore, without adoptive transfer, very low intracerebral doses of docile virus (which mimicked the normally slow spread of aggressive virus) were lethal. On the other hand, very high doses of aggressive virus, which mimicked the normally rapid spread of docile virus, did not induce fatal CNS disease. The results suggest that rapid dissemination of the LCM infection creates multiple target organs which divert the focused lethal T cell attack on the brain.
Idiotype-anti-idiotype network. II. Activation of silent clones by treatment at birth with idiotypes is associated with the expansion of idiotype-specific helper T cells.
Authors: Rubinstein L J , Yeh M , Bona C A
Published: June 2004

BALB/c mice immunized with bacterial levan (BL) produce a vigorous antibody response that fails to include antibodies expressing the idiotype of the beta 2 leads to 6 fructosan-binding myeloma protein ABPC48 (A48). Treatment of newborn BALB/c mice at 1 d of age with 0.1-10 microgram of either the A48 myeloma protein or monoclonal proteins that share idiotopes with the A48 family, followed by immunization with BL 2-4 wk later, produces an anti-BL response that is dominated by the A48Id. Various degrees of activation of the A48Id BL response were observed by injecting mice with A48 monoclonal protein only up until 3 wk of age. Activation of the A48Id clones by treating with A48 monoclonal protein was ineffective in mice who were older than 4 wk. Elicitation of an A48Id BL response required specific antigenic stimulation with either beta 2 leads to 6 or beta 2 leads to 1 fructosan epitopes, because it does not occur after injection with TNP-Ficoll in spite of the A48 treatment. The expansion of A48Id clones in mice treated at birth with A48 monoclonal protein is associated with an increase in A48Id-specific helper T cells. The binding specificity of these cells was demonstrated by infusing them into nu/nu BALB/c mice and observing that they rendered help that enalbed the animal to mount an anti-TNP response after immunization only with A48-TNP, but not with MOPC384-TNP conjugates. The helper activity of these cells is sensitive to the effects of treatment with anti-Lyt-1.2 antibodies plus complement. A predominantly A48Id BL-specific response can be transferred into lethally irradiated mice by infusing them with purified T and B cells from A48-treated mice. The transfer of this response can be ablated by treating the T cells with anti-Lyt-1.2 antibodies plus complement. These results indicate that A48Id-specific helper cells possess the ability to select the A48Id-bearing B cell precursors for expression, thus exerting a fine-tuning effect on the idiotypic expression of the anti-BL repertoire. We propose that this idiotype-induced idiotype response, which can be, in principal, induced by idiotypes provided by the mother, plays an important role in the expansion of precursors of antibody-forming cells during embryonic as well as postnatal life.