Multiaperture ion beam extraction from gas-dynamic electron cyclotron resonance source of multicharged ions

Electron cyclotron resonance ion source with quasi-gas-dynamic regime of plasma confinement (ReGIS), constructed at the Institute of Applied Physics, Russia, provides opportunities for extracting intense and high-brightness multicharged ion beams. Despite the short plasma lifetime in a magnetic trap of a ReGIS, the degree of multiple ionization may be significantly enhanced by the increase in power and frequency of the applied microwave radiation. The present work is focused on studying the intense beam quality of this source by the pepper-pot method. A single beamlet emittance measured by the pepper-pot method was found to be approximately 70 pi mm mrad, and the total extracted beam current obtained at 14 kV extraction voltage was approximately 25 mA. The results of the numerical simulations of ion beam extraction are found to be in good agreement with experimental data.

Inflammatory chemokine transport and presentation in HEV: a remote control mechanism for monocyte recruitment to lymph nodes in inflamed tissues

Interstitial fluid is constantly drained into lymph nodes (LNs) via afferent lymph vessels. This conduit enables monocyte-derived macrophages and dendritic cells to access LNs from peripheral tissues. We show that during inflammation in the skin, a second recruitment pathway is evoked that recruits large numbers of blood-borne monocytes to LNs via high endothelial venules (HEVs). Inhibition of monocyte chemoattractant protein (MCP)-1 blocked this inflammation-induced monocyte homing to LNs. MCP-1 mRNA in inflamed skin was over 100-fold upregulated and paralleled MCP-1 protein levels, whereas in draining LNs MCP-1 mRNA induction was much weaker and occurred only after a pronounced rise in MCP-1 protein. Thus, MCP-1 in draining LNs was primarily derived from inflamed skin. In MCP-1(-/-) mice, intracutaneously injected MCP-1 accumulated rapidly in the draining LNs where it enhanced monocyte recruitment. Intravital microscopy showed that skin-derived MCP-1 was transported via the lymph to the luminal surface of HEVs where it triggered integrin-dependent arrest of rolling monocytes. These findings demonstrate that inflamed peripheral tissues project their local chemokine profile to HEVs in draining LNs and thereby exert "remote control" over the composition of leukocyte populations that home to these organs from the blood.

The coordinated action of CC chemokines in the lung orchestrates allergic inflammation and airway hyperresponsiveness

The complex pathophysiology of lung allergic inflammation and bronchial hyperresponsiveness (BHR) that characterize asthma is achieved by the regulated accumulation and activation of different leukocyte subsets in the lung. The development and maintenance of these processes correlate with the coordinated production of chemokines. Here, we have assessed the role that different chemokines play in lung allergic inflammation and BHR by blocking their activities in vivo. Our results show that blockage of each one of these chemokines reduces both lung leukocyte infiltration and BHR in a substantially different way. Thus, eotaxin neutralization reduces specifically BHR and lung eosinophilia transiently after each antigen exposure. Monocyte chemoattractant protein (MCP)-5 neutralization abolishes BHR not by affecting the accumulation of inflammatory leukocytes in the airways, but rather by altering the trafficking of the eosinophils and other leukocytes through the lung interstitium. Neutralization of RANTES (regulated upon activation, normal T cell expressed and secreted) receptor(s) with a receptor antagonist decreases significantly lymphocyte and eosinophil infiltration as well as mRNA expression of eotaxin and RANTES. In contrast, neutralization of one of the ligands for RANTES receptors, macrophage-inflammatory protein 1alpha, reduces only slightly lung eosinophilia and BHR. Finally, MCP-1 neutralization diminishes drastically BHR and inflammation, and this correlates with a pronounced decrease in monocyte- and lymphocyte-derived inflammatory mediators. These results suggest that different chemokines activate different cellular and molecular pathways that in a coordinated fashion contribute to the complex pathophysiology of asthma, and that their individual blockage results in intervention at different levels of these processes.

[Glycoprotein D (5-23) specific Th2-T-cell line induces HSV-1 keratitis]

BALB/c inbred Igh-1-disparate mice exhibit different susceptibility to the development of HSV-1 stromal keratitis (HSK), which may be due to the differential immune regulation. CD4+ T lymphocytes may be critical for the disease induction. A T-cell line (CD4+, T-cell receptor V beta 8+, interleukin-4+) specific for the N-terminal amino acids 5-23 of glycoprotein D from HSV-1 [gD(5-23)] was established from HSK susceptible C.AL-20 mice. HSK-resistant C.B-17 mice, and HSK-susceptible BALB/c mice were injected intraperitoneally with cells (5 x 10(5)/mouse) alone or combined with HSV-1 corneal inoculation (10(5) PFU, KOS strain). Control groups were injected with HSV-antigen-unrelated cells (PPD specific), or were only HSV-1 infected. Migration of the adoptively transferred gD(5-23) Th2 cells was analyzed by histology, by immunohistochemistry and by cell membrane labelling (PKH26). The transfer of gD(5-23) cells accelerated the disease onset (day 2, compared to day 7 without cells). The transfer of gD(5-23) cells increased the incidence of HSK (BALB/c 100%, C.B-17 20%) compared to mice that were only infected with HSV-1 (BALB/c 75%, C.B-17 0%). Keratitis was more severe in mice injected with gD(5-23) cells. In contrast, the transfer of PPD-specific cells did not influence the disease patterns. Mice injected with gD(5-23) cells and not inoculated with HSV-1 did not develop keratitis. The results suggest that CD4+ MHC class II, V beta 8+, IL-4 expressing T-cells (T helper 2) may be important for the induction of HSK.(ABSTRACT TRUNCATED AT 250 WORDS)

Experimental autoimmune encephalomyelitis-resistant mice have highly encephalitogenic myelin basic protein (MBP)-specific T cell clones that recognize a MBP peptide with high affinity for MHC class II

BALB/c mice are resistant to disease induction when experimental protocols that induce experimental autoimmune encephalomyelitis (EAE) in susceptible strains of animals are used. We have previously described a panel of myelin basic protein (MBP)-specific CD4+ T cell clones from BALB/c mice, two of which induce moderate EAE when transferred to syngeneic recipients. These clones are I-E(d) restricted and recognize residues 151-160 of mouse MBP. Here, we describe a series of 17 MBP-reactive T cell clones, which were derived from two BALB/c mice. All are I-A(d) restricted and recognize nested epitopes in peptide 59-76 of mouse MBP. Four different TCR V beta chains are used by this panel of clones; these include V beta 8.2 (10/17), V beta 8.1 (2/17), V beta 7 (3/17), and V beta 14 (2/17). Twelve of fourteen clones tested adoptively transferred severe demyelinating EAE to syngeneic recipients. Studies of relative binding affinities of MBP peptides to class II molecules I-A(d) and I-E(d) show that peptide 59-76 binds with extremely high affinity to I-A(d), whereas three peptides that contains residues 151-160 bind poorly to I-E(d). These results are consistent with a growing number of reports that show that high affinity binding to class II is required for autoantigenic stimulation. Despite encephalitogenicity of 59-76-reactive T cells, active immunization of BALB/c mice with peptide 59-76 in adjuvant failed to induce either clinical or histologic signs of EAE. The implications of these findings for mechanisms of genetically determined EAE resistance are discussed.

Experimental autoimmune encephalomyelitis-resistant mice have highly encephalitogenic myelin basic protein (MBP)-specific T cell clones that recognize a MBP peptide with high affinity for MHC class II

BALB/c mice are resistant to disease induction when experimental protocols that induce experimental autoimmune encephalomyelitis (EAE) in susceptible strains of animals are used. We have previously described a panel of myelin basic protein (MBP)-specific CD4+ T cell clones from BALB/c mice, two of which induce moderate EAE when transferred to syngeneic recipients. These clones are I-E(d) restricted and recognize residues 151-160 of mouse MBP. Here, we describe a series of 17 MBP-reactive T cell clones, which were derived from two BALB/c mice. All are I-A(d) restricted and recognize nested epitopes in peptide 59-76 of mouse MBP. Four different TCR V beta chains are used by this panel of clones; these include V beta 8.2 (10/17), V beta 8.1 (2/17), V beta 7 (3/17), and V beta 14 (2/17). Twelve of fourteen clones tested adoptively transferred severe demyelinating EAE to syngeneic recipients. Studies of relative binding affinities of MBP peptides to class II molecules I-A(d) and I-E(d) show that peptide 59-76 binds with extremely high affinity to I-A(d), whereas three peptides that contains residues 151-160 bind poorly to I-E(d). These results are consistent with a growing number of reports that show that high affinity binding to class II is required for autoantigenic stimulation. Despite encephalitogenicity of 59-76-reactive T cells, active immunization of BALB/c mice with peptide 59-76 in adjuvant failed to induce either clinical or histologic signs of EAE. The implications of these findings for mechanisms of genetically determined EAE resistance are discussed.

Analysis of an in vitro-generated signal that induces systemic immune deviation similar to that elicited by antigen injected into the anterior chamber of the eye

The selective deficit in delayed hypersensitivity that characterizes anterior chamber-associated immune deviation (ACAID) is the direct result of a blood borne, Ag-specific, cell-associated signal that is created after Ag is injected into the anterior chamber of the eye of normal mice. The cells that carry this signal via the blood to the spleen express the mature macrophage marker F4/80 and are similar to, or perhaps even arise from, F4/80+ dendritic cells found within the stroma of normal iris and ciliary body. We have recently reported that ACAID-inducing properties can be conferred upon conventional F4/80-bearing macrophages harvested from the normal peritoneal cavity by incubating these cells in vitro with the soluble protein Ag, BSA, in the presence of supernatants harvested from cultured iris and ciliary body cells. Using this in vitro induction system, we have examined the limiting conditions for conferring ACAID-inducing potential on peritoneal exudate cells. We have found that an ACAID-inducing signal can be created in vitro with several different soluble Ag, including the retinal autoantigen-interphotoreceptor retinol binding protein, and that active endocytosis and processing by peritoneal exudate cells is required because chloroquine prevents these cells from acquiring ACAID-inducing properties. In addition, we have determined that for supernatant-treated peritoneal macrophages to induce ACAID to soluble Ag the cells must be 1) alive, 2) injected i.v. or i.p. (but not s.c.), and 3) administered to recipients with an anatomically intact spleen. When these conditions are met, as few as 20 F4/80+ macrophages pulsed with Ag in the presence of iris and ciliary body supernatants are sufficient to induce ACAID. Macrophage hybridomas derived from "conventional" APC can acquire ACAID-inducing potential in vitro if exposed to iris and ciliary body supernatants, whereas macrophage hybridomas derived from "suppressor inducer" APC constitutively possess ACAID-induced potential. Peritoneal macrophages that were endowed with ACAID-inducing properties by in vitro exposure to supernatants were found to elicit splenic suppressor cells similar to those found in spleens of mice with ACAID. Moreover, the expression of experimental autoimmune uveitis in mice immunized with interphotoreceptor retinol binding protein was significantly suppressed if the animals were pretreated with peritoneal exudate cells pulsed with this Ag in the presence of iris and ciliary body supernatants.(ABSTRACT TRUNCATED AT 400 WORDS)

Analysis of an in vitro-generated signal that induces systemic immune deviation similar to that elicited by antigen injected into the anterior chamber of the eye

The selective deficit in delayed hypersensitivity that characterizes anterior chamber-associated immune deviation (ACAID) is the direct result of a blood borne, Ag-specific, cell-associated signal that is created after Ag is injected into the anterior chamber of the eye of normal mice. The cells that carry this signal via the blood to the spleen express the mature macrophage marker F4/80 and are similar to, or perhaps even arise from, F4/80+ dendritic cells found within the stroma of normal iris and ciliary body. We have recently reported that ACAID-inducing properties can be conferred upon conventional F4/80-bearing macrophages harvested from the normal peritoneal cavity by incubating these cells in vitro with the soluble protein Ag, BSA, in the presence of supernatants harvested from cultured iris and ciliary body cells. Using this in vitro induction system, we have examined the limiting conditions for conferring ACAID-inducing potential on peritoneal exudate cells. We have found that an ACAID-inducing signal can be created in vitro with several different soluble Ag, including the retinal autoantigen-interphotoreceptor retinol binding protein, and that active endocytosis and processing by peritoneal exudate cells is required because chloroquine prevents these cells from acquiring ACAID-inducing properties. In addition, we have determined that for supernatant-treated peritoneal macrophages to induce ACAID to soluble Ag the cells must be 1) alive, 2) injected i.v. or i.p. (but not s.c.), and 3) administered to recipients with an anatomically intact spleen. When these conditions are met, as few as 20 F4/80+ macrophages pulsed with Ag in the presence of iris and ciliary body supernatants are sufficient to induce ACAID. Macrophage hybridomas derived from "conventional" APC can acquire ACAID-inducing potential in vitro if exposed to iris and ciliary body supernatants, whereas macrophage hybridomas derived from "suppressor inducer" APC constitutively possess ACAID-induced potential. Peritoneal macrophages that were endowed with ACAID-inducing properties by in vitro exposure to supernatants were found to elicit splenic suppressor cells similar to those found in spleens of mice with ACAID. Moreover, the expression of experimental autoimmune uveitis in mice immunized with interphotoreceptor retinol binding protein was significantly suppressed if the animals were pretreated with peritoneal exudate cells pulsed with this Ag in the presence of iris and ciliary body supernatants.(ABSTRACT TRUNCATED AT 400 WORDS)

Rearrangement and transcription of a T-cell receptor beta-chain gene in different T-cell subsets

The functionally defined sets of T lymphocytes--helper T cells, cytotoxic T cells, and suppressor T cells--were examined for the possible involvement of a recently identified T-cell receptor beta gene locus in receptor formation. Since gene rearrangements are required for functional gene expression, cloned T-cell lines from each of the groups were surveyed for the expression of unique gene rearrangements. In addition, cell lines that showed gene rearrangements were further tested for the expression of the mature 1.2- to 1.3-kilobase mRNA transcribed from a productive gene rearrangement. The results of such experiments show that helper and cytotoxic T cells may use a common beta chain of the receptor, whereas suppressor cells do so rarely, if at all.

Determinants of antigenic molecules responsible for genetically controlled regulation of immune responses

The ability of mice bearing the H-2S haplotype to develop helper responses to the random copolymer of Glu,Ala while they developed suppressor responses to the terpolymer of Glu,Ala,Tyr suggested the crucial role of tyrosine in these peptides. On the basis of various considerations, it was postulated that many of the tyrosine residues in Glu,Ala,Tyr would be localized at the NH2-terminal end of the molecule. To verify this hypothesis, a block terpolymer composed of a short sequence of homopolymer tyrosine covalently bound to the random copolymer of Glu,Ala was synthesized. The present studies, using this block terpolymer, demonstrated that the chemical determinants stimulating helper and suppressor responses are distinct and can be present simultaneously in the same molecule. Thus, addition of COOH-terminal tyrosine residues to the Glu,Ala polypeptide converted this immunogenic molecule to an immunosuppressive molecule in mice bearing the H-2S haplotype. The mechanism by which these short sequences of tyrosine influence H-2-linked immune responses remains to be determined.

Genetic control of specific immune suppression. III. Mapping of H-2 complex complementing genes controlling immune suppression by the random copolymer L-glutamic acid50-L-tyrosine50 (GT)

Earlier studies from our laboratory demonstrated that the terpolymer of L-glutamic acid, L-alanine, and L-tyrpsine (GAT) stimulated the development of T cells capable of specifically suppressing the antibody responses in vivo and in vitro of nonresponder strains (bearing the H-2(s), H-2(q), and H-2(p) haplotypes) to GAT complexed with an immunogenic carrier, methylated bovine serum albumin, MBSA (1,2). We then extended these findings to another antigen, the copolymer of L-glutamic acid and L-tyrosine (GT). None of 19 inbred or congenic resistant mouse strains developed antibody responses to GT after immunization with this synthetic polypeptide in adjuvants. All the strains investigated, however, developed IgG plaque-forming cells (PFC) primary responses to GT complexed with MBSA (3). This permitted us to determine that: (a) preimmunization with GT suppressed the response to GT-MBSA in certain but not in all strains; (b) the suppression could be transferred by thymocytes and spleen cells from GT-primed animals; (c) the development of GT-specific suppressor cells is under dominant control of H-2- linked gene(s) which have been designated specific immune suppressor genes (Is genes); (d) the Is genes are antigen specific since GAT-MBSA responses are suppressed by GAT in strains carrying the H-2(q) haplotype, while GT-MBSA responses are not suppressed by the related polymer GT in these same strains (3,4). The experiments reported in this study map the Is genes responsible for GT-specific suppression within the H-2 complex. The data indicate that the K and D loci are not concerned with GT-specific suppression, and that this phenomenon is controlled by complementing or interacting genes which map on either side of cross-over events between the IB and IC subregions.