bluuebunny/crossref_metadata_2025 huggingface dataset:
Bactericidal activity of the alternative complement pathway generated from 11 isolated plasma proteins.
Authors: Schreiber R D , Morrison D C , Podack E R , Müller-Eberhard H J
Published: June 2004

Exposure of E. coli K12 W1485 to the cytolytic alternative pathway assembled from the 11 isolated pathway proteins resulted in killing of the bacteria, as evidenced by loss of viability. Lysis of the bacteria required introduction of lysozyme into the reaction mixture. The time-course and dose dependency of bacteriolysis in the isolated system were identical to those in C4-depleted serum. The bacteriolytic activity of the pathway was highly dependent on the concentration of the pathway proteins and became insignificant at 1:16 physiological concentration. Electron microscopic visualization of killed and of lysed bacteria revealed numerous complement membrane lesions and partial disintegration of the outer phospholipid membrane. Scanning electron microscopy showed that killed bacteria were enlarged, partially collapsed and exhibited irregular surface protrusions. Lysed bacteria were fragmented and appeared polymorphic. This study demonstrates that the alternative pathway, in absence of immunoglobulins, has the potential or eradicating gram-negative bacteria.
Neutral protease secretion by human monocytes. Effect of surface-bound immune complexes.
Authors: Ragsdale C G , Arend W P
Published: June 2004

The effect of surface-bound immune complexes on the secretion of neutral proteases by human peripheral monocytes was examined. Monocytes cultured on 125I-fibrin secreted plasminogen activator in a continuous fashion. Monocytes incubated on 125I-fibrin with surface-bound immune complexes displayed a burst of plasminogen-independent fibrinolytic activity, whereas no release of plasminogen activator was observed through 21 h. The plasminogen-independent fibrinolytic enzymes were derived from monocytes and not from lymphocytes or contaminating polymorphonuclear neutrophils. The effects of various protease inhibitors on the secretion of plasminogen-dependent and independent enzymes were determined. Chymostatin selectively inhibited the monocyte-derived plasminogen activators. Similar effects of chymostatin were observed on human urokinase in the absence of cells. The predominant protease producing plasminogen-independent fibrinolysis exhibited responses to inhibitors characteristic of leukocyte elastase. When monocytes were cultured on 125I-fibrin with adherent immune complexes approximately equal to 40% of the solubilized radioactivity represented deiodination and not proteolysis. It was concluded that culture of human monocytes on surface-bound immune complexes stimulates the secretion of plasminogen-independent fibrinolytic proteases, primarily elastase, and of deiodinating enzymes. Under these conditions, plasminogen activator secretion is inhibited. Neutral proteases secreted from newly recruited monocytes may contribute to tissue injury in human diseases characterized by the presence of adherent immune complexes.
Cyclophosphamide eliminates suppressor T cells in age-associated central regulation of delayed hypersensitivity in mice.
Authors: Mitsuoka A , Morikawa S , Baba M , Harada T
Published: June 2004

Effect of treatment of mice with cyclophosphamide (CY) on the delayed hypersensitivity (DH) response was investigated in C57BL/6 mice. DH to methylated human serum albumin (MHSA) could be enhanced with CY in young mice but not in aged ones. DH enhancement with CY appeared to be due to elimination of suppressor T cells involved in DH. Effector T cells were also sensitive to CY, the damaging effect of CY on these latter cells was, however, transient suggesting the rapid recovery of effector T cells. The overshooting recovery of the effector T cells required the presence of the thymus. It is more probably that there are at least two distinct subpopulations of T cells in DH, effector T cells, and suppressor T cells. The distinction is already apparent in the thymus stage. The suppressor T cells, categorized as a central regulator, seem to be antigen nonspecific and regulate the more effectively the DH in young mice, thus physiological role of these cells in age-associated immune alterations is implicated.
Cytokinetic analysis of the impaired proliferative response of peripheral lymphocytes from aged humans to phytohemagglutinin.
Authors: Tice R R , Schneider E L , Kram D , Thorne P
Published: June 2004

The effect of donor age on the rate of cell entry into the proliferating pool and subsequent cell cycle duration for peripheral lymphocytes stimulated by phytohemagglutinin (PHA) were examined by using the bromodeoxyuridine incorporation-differential staining technique. Distribution curves for the appearance of metaphase cells in successive generations as a function of culture time were obtained and analyzed both graphically and by a computer simulation model. Peripheral lymphocytes from aged individuals (approximately 75 yr) were stimulated by PHA at approximately one-half of the rate of peripheral lymphocytes from young individuals (approximately 21 yr). Subsequent cell-cycle durations were estimated to range from 10.0 to 25.0 h for aged individual lymphocyte cultures and 10.6-15.6 h for young individual lymphocyte cultures. The possible significance of these findings to aging in general is discussed.
Transfer of specific unresponsiveness to organ allografts by thymocytes. Specific unresponsiveness by thymocyte transfer.
Authors: Hendry W S , Tilney N L , Baldwin W M , Graves M J , Milford E , Strom T B , Carpenter C B
Published: June 2004

Prolonged survival of vascularized organ allografts has been produced in unmodified inbred rats by transfer of thymocytes from enhanced, engrafted, syngeneic animals. For these thymocytes to increase significantly the survival of test allografts they must be harvested 6-9 d after transplantation. Thymectomy of the enhanced, engrafted animals during the same critical period causes acute rejection of othewise long surviving grafts. For optimal effect, the enhanced thymocyte donor must be actively and passively immunized and receive a cardiac allograft. The necessity for erythrocytes in the initial active immunization regimen is noted. Additionally, the antigenic specificity of the suppressor effect has been established with two histoincompatible donor rat strains. Cellular and humoral host responses mounted by test graft recipients after thymocyte transfer from enhanced, engrafted donors are different from those mounted either by unmodifed animals acutely rejecting their grafts or by enhanced rats bearing well-functioning grafts. Numbers of T lymphocytes are reduced in the grafted hearts and in the spleens of test graft recipients, a finding paralleled by the complete absence of specific direct lymphocyte-mediated cytotoxicity. In contrast, cytotoxic antibody production, although delayed, is increased in magnitude, peaking around the time of graft rejection. These studies provide evidence that different biological manipulations can modify separate pathways in the complex cellular and humoral responses towards organ allografts. They demonstrate that cellular immunity is critically involved in immunological enhancement of vascularized organ allografts, a phenomenon hitherto considered primarily humoral. It seems clear that cells with suppressor activity are present within the thymus during the early phases of immunological enhancement.
Mechanism of rejection of virus persistently infected tumor cells by athymic nude mice.
Authors: Minato N , Bloom B R , Jones C , Holland J , Reid L M
Published: June 2004

Cell lines known to be tumorigenic in the nude mouse were modified by rendering them persistently infected (P.I.) with a variety of RNA viruses, including measles, mumps, vesicular stomatitis virus, and influenza. Although as few as 100 HeLa or BHK cells produced tumors in 100% of nude mice, as many as 2 x 10(7) of the same cells P.I. with viruses failed to produce tumors. An active host response responsible for restricting the growth of the P.I. cells was suggested by the findings of marked mononuclear cell infiltrates at the inoculation sites and the inability of irradiated nude mice to reject them. An analysis of the in vitro cytotoxic activity of spleen cells from normal nude mice indicated that: (a) P.I. cell lines, but not uninfected cell lines, were susceptible to spontaneous cytotoxicity; (b) in vivo inoculation of P.I. lines induced an enhanced cytotoxic activity for P.I. targets in vitro, and this induction was not specific either for inducing virus or cell line; and (c) the effector cell had the characteristics for natural killer (NK) cells. Although the specificity of recognition of the various P.I. cell lines remains unclear, cold competition experiments indicated that blocking the killing of one P.I. cell line, e.g. HeLa-measles, could be achieved only by unlabeled homologous cells, i.e. HeLa-measles, and not by uninfected cells or other P.I. lines. A variant subline of BHK cells P.I. with VSV was selected for its ability to withstand the rejection process in nude mice. These cells formed metastatic and invasive tumors in nude mice. Although they were the most potent inducers in vivo of NK cell activity against various P.I. targets, they were the most resistant of the P.I. lines to NK cell cytotoxicity in vitro. In this system there was a good correlation between tumor rejection in vivo and susceptibility to NK cells in vitro. The present results suggest that NK cells may play a significant role in both rejection of tumor cells, and in resistance to viruses, particularly persistent infections.
Endothelial injury in scleroderma.
Authors: Kahaleh M B , Sherer G K , LeRoy E C
Published: June 2004

Functional and structural vascular lesions have been observed in the organs involved in scleroderma. The etiology of these vascular changes is poorly understood. The ability to isolate, characterize, and maintain endothelial cells in vitro provides a target cell population to study endothelial damage in scleroderma. The present report describes the effect of scleroderma serum on endothelial, smooth muscle, and fibroblast cell types. Sera from patients with scleroderma (31/52) and Raynaud's syndrome (11/19) contain cytotoxic activity, specific for endothelial cells, which is nondialyzable, heat-stable, and elutes with albumin on gel-filtration chromatography.
Rosette formation between murine lymphocytes and erythrocytes. A new locus in the H-2 region.
Authors: Primi D , Lewis G K , Triglia R , Goodman J W
Published: June 2004

More than 5% of murine splenic lymphocytes form rosettes with syngeneic erythrocytes. This property was maximally expressed when the lymphocytes were cultured for 24 h before rosetting. About 70% of the rosetting lymphocytes were B cells and 30% were T cells on the basis of surface immunoglobulin and the Thy-1-antigen. Capping surface immunoglobulin had no effect on the capacity of lymphocytes to form rosettes, indicating that the receptor in question was not immunoglobulin. The capacity of lymphocytes to form rosettes with erythrocytes from other strains of mice was H-2 restricted. Extensive pairings of congenic and recombinant strains as donors of lymphocytes and erythrocytes showed that none of the known loci within the H-2 region-controlled rosetting. The involvement of regions on chromosome 17, telomeric or centromeric to H-2, was also excluded. The data were only compatible with the conclusion that this form of self-recognition is associated with a new locus (or loci) mapping between H-2G and H-2D.
Adaptive differentiation of murine lymphocytes. II. The thymic microenvironment does not restrict the cooperative partner cell preference of helper T cells differentiating in F1 leads to F1 thymic chimeras.
Authors: Katz D H , Katz L R , Bogowitz C A , Skidmore B J
Published: June 2004

The cooperating preference of helper T cells originating from F1 bone marrow, but differentiating in adult thymectomized, lethally irradiated F1 recipients reconstituted with either f1 or homozygous parental thymus grafts was investigated. Cooperating preference was assayed by determining the levels of helper activity provided by antigen-primed T cells derived from such thymic chimeras for hapten-primed B lymphocytes obtained from conventional F1 or parental donors in adoptive secondary antibody responses in vivo. The results of these analyses revealed a tendency of helper T cells derived from parental thymic chimeras to provide better help for B cells of the same parental type corresponding to the origin of the thymus graft than for the opposite parent. Such preference was, however, only marginal and rarely were differences in levels of helper activity provided to the respective parental types statistically significant. Moreover, this marginal preference, when observed, pertained only to responses of the IgG class; no concordant preference in providing helper activity for IgE antibody responses was observed even with the same populations of thymic chimera helper T cells. Finally, in no instance was there any evidence of restriction in the classical sense of presence versus absence of help as we have routinely observed in all of our previous studies concerning genetic restrictions of T-B-cell cooperative interactions. Although the basis for differences in the studies reported here when compared to observations made in cytotoxic T-lymphocyte systems is unclear, and could reflect genuine mechanistic requirements concerning what directs H-2 restrictions in helper T cells and cytotoxic T lymphocytes, respectively, it is also possible that we are placing too much faith in our interpretations of data obtained in bone marrow chimera systems than is perhaps justified by the potentially great fragility of such systems.
Isolation and immunological characterization of a major surface glycoprotein (gp54) preferentially expressed on certain human B cells.
Authors: Wang C Y , Fu S M , Kunkel H G
Published: June 2004

A major membrane glycoprotein with mol wt of approximately 54,000 has been isolated from membrane preparations of B-type lymphoid cell lines. Antiserum prepared against the isolated material specifically precipitated this glycoprotein from membranes labeled by surface radioiodination or by metabolic labeling. This antiserum was shown by complement-mediated cytotoxicity assay, membrane immunofluorescent staining, and by quantitative absorption analysis to react preferentially with certain B-lymphoblastoid cell lines, with a minor population of peripheral blood B lymphocytes, and a major population of tonsillar B lymphocytes. Certain B-cell leukemias also expressed the antigen, whereas others did not. Considerable variability was observed among positive B cells in the intensity of fluorescent staining even among the leukemic cells from a single individual. Although T cells, including T cells, were negative by direct immunofluorescent and cytotoxicity assay, evidence for low levels of the antigen on the cells of T cell lines was obtained. The whole specific antiserum and its F(ab')2 fragments stimulated B lymphocytes to proliferate. This proliferation did not produce differentiation to plasma cells and was T-cell independent. The monovalent Fab fragments had no effect. None of these preparations timulated T cells. The possibility that this antigen, termed gp54, may play some role in B-cell activation is discussed.
Basal lamina heterogeneity in the glomerular capillary tufts of human kidneys
Authors: Huang TW
Published: June 2004

Two classes of glomerular basal laminas are identified with a newly developed guanidine technique. The electron-opaque epithelial basal lamina is the most prominent element of the glomerular basal lamina scaffold. It is a continuous layer within each glomerulus, folding into capillary tufts and loops, but never completely encircling the entire circumference of each capillary, similar to the serosa covering the intestinal loop and mesentery. The vascular space so defined is further partitioned into individual capillary lumen by an electron-lucent mesangial basal lamina, that forms a meshwork continuous with the vascular pole of the glomerulus and extends peripherally to surround capillary lumens. The latter, designated endothelial basal lamina, is extremely attenuated and appears as a vestigial structure in glomerular capillary loops. Changes in juxtamesangial epithelial basal lamina indicate that it may be the site of the bulk removal and renewal of the epithelial basal lamina.

The unique epithelial origin of glomerular capillary basal lamina and its organization provide a structural basis for understanding the glomerular physiology gained by various tracer studies. The results also suggest that the guanidine technique may be a useful new approach to the analysis of basal lamina alterations in various glomerular diseases.
Ef2: a new LY-3-linked light-chain marker expressed in normal mouse serum immunoglobulin.
Authors: Gibson D M , MacLean S J
Published: June 2004

A new light-chain marker has been detected in normal mouse serum immunoglobulin light chains by gel isoelectric focusing. The marker (Ef2) involves the presence of two major and several minor bands in the normal light-chain IF profiles. Strains expressing the marker IF bands are designated Igk-Ef2a, whereas those lacking the bands are Igk-Ef2b. The majority of inbred strains are Igk-Ef2a. Strains found to be Igk-Ef2b are NZB/BlNJ, BDP/J, C58/J, I/LnJ, CE/J, and P/J. The strain distribution of the alleles differs from the distribution of alleles at the Ly-2 and Ly-3 loci, suggesting the new marker may represent a separate locus. Genetic studies have shown that Igk-Ef2 locus is closely linked to Igk-Ef1 and Hd loci on Chromosome 6, indicating that it is also closely linked to Ly-3. The relative importance of the bands controlled by the Igk-Ef2 locus suggests that the entire normal light-chain pool could be controlled by as few as 100 such loci.
Release of arachidonic acid from human lymphocytes in response to mitogenic lectins.
Authors: Parker C W , Kelly J P , Falkenhein S F , Huber M G
Published: June 2004

After exposure to mitogenic lectins in vitro, human mononuclear cells (95% lymphocytes) that had been prelabeled with [14C]arachidonic acid rapidly released a portion of their radioactivity in the medium. Most of the released radioactivity was demonstrated to be free arachidonic acid. Although other sources are not excluded, the most important source of cell-bound radioactivity in the release reaction appeared to be phosphatidylinositol, suggesting that at least part of the response is occurring through an increase in phospholipase A2 activity. By gas liquid chromatography, other fatty acids were also shown to be released, but there was considerable selectivity in the response for arachidonic acid. The response was dependent on the availability of free Ca++ in the medium and was enhanced by serum proteins and unlabeled arachidonic acid. Most of the response appeared to be from the the lymphocytes themselves rather than from contaminating cells. The rapid generation of free arachidonic acid in response to mitogenic lectins suggests a possible role for arachidonic acid metabolites in the activation process.
Age-dependent production of IgA and IgM autoantibodies against IgG2a in a colony of 129/Sv mice
Authors: Van Snick JL , Masson PL
Published: June 2004

Although much of the basic immunological work has been done with mice, little is known about anti-IgG autoantibodies in this species. Dresser (1, 2) has reported the occurrence, in CBA mice, of anti-IgG antibody (Ab)(1) detected by a hemolytic-plaque assay after stimulation with endotoxin or immunization against sheep erythrocytes. IgM rheumatoid factor has also been described in various strains of mice with a systemic lupus erythematosus-like disease (3). Recently, we have tried to induce anti-IgG in mice of the 129/Sv strain by inoculating autologous IgG. To our surprise, we found that the sera of all the animals had, before any inoculation, anti-IgG detectable by agglutination of particles coated with autologous IgG. The possibilities to investigate the mechanism of production and the biological role of this kind of Ab prompted us to undertake a study of the nature and specificity of the mouse anti-IgG.
Evidence for two homologous, but nonidentical, Ia molecules determined by the I-EC subregion.
Authors: Delovitch T L , Barber B H
Published: June 2004

Sequential immunoprecipitation, two-dimensional gel electrophoresis and peptide mapping analyses of B10A(3R), 35S-methionine-labeled, I-EC subregion products were performed. Evidence is presented here for the presence of two structurally homologous, but nonidentical, gene products of the I-EC subregion. These two Ia molecules are independently immunoprecipitable, identical in molecular size and charge, but differ by approximately equal to 20% in their peptides obtained by partial digestion with Staphylococcus aureus protease V8.
Production of auto-anti-idiotypic antibody during the normal immune response to TNP-ficoll. II. Hapten-reversible inhibition of anti-TNP plaque-forming cells by immune serum as an assay for auto-anti-idiotypic antibody
Authors: Goidl EA , Shrater AF , Siskind GW , Thorbecke GJ
Published: June 2004

Sera taken from AKR/J mice 7 d after the intravenous injection of 2,4,6-trinitrophenyl-lys-Ficoll (TNP-F) caused a specific inhibition of anti- trinitrophenol (TNP) plaque-forming cells (PFC) in vitro. This inhibition was reversed by the incorporation of 10(-8)-10(-7) M 2,4,6-trinitrophenyl- ε-amino-n-caproic acid (TNP-EACA) into the agar during the PFC assay. The factor responsible for the hapten-reversible PFC inhibition was removed from serum by passage through an anti-immunoglobulin column or through a 2,4,-dinitrophenyl-human-serum-albumin-bromoacetylcellulose plus anti-TNP- antibody column, but not by DNP-HSA-BAC alone. It was concluded that this immunoglobulin-like substance, lacking anti-TNP activity but reacting with anti-TNP antibody of AKR/J origin, was most likely an auto-anti-idiotypie antibody that had been produced during the normal course of the response of AKR/J mice to TNP-F. Pools of anti-idiotypic-antibody-containing antisera inhibited anti-TNP plaque formation to varying degrees when tested on d-4 PFC from different mice of the same inbred strain, suggesting a variability in idiotype expression.

4 d after transfer of immune (7 d after 10 μg TNP-F, administered intravenously) AKR/J spleen cells plus 10 μg TNP-F into syngeneic mice, the number of PFC detectable in the recipients' spleens could be markedly augmented by the inclusion of TNP-EACA in the agar during the PFC assay. Incubation of spleen cells containing such hapten-augmentable PFC with TNP- EACA yielded a factor in the supernate that caused a specific, in vitro, hapten-reversible inhibition of anti-TNP PFC. Studies with immunoadsorbents indicated that this PFC-inhibiting factor was antigenically immunoglobulin- like, lacked anti-TNP-antibody activity, but reacted with anti-TNP antibody of AKR/J origin. The results are consistent with the view that this PFC inhibitor is auto-anti-idiotypic antibody that is involved in the normal regulation of the immune response.

It is proposed that hapten-reversible inhibition of plaque formation can be employed as an assay for anti-idiotypic antibody and the conditions for such an assay are described. It is further proposed that the detection of hapten-augmentable PFC suggests the presence of auto-anti-idiotypic antibody.
Different D end-dependent antigenic determinants are recognized by H-2-restricted cytotoxic T cells specific for influenza and Bebaru viruses.
Authors: Blanden R V , Müllbacher A , Ashman R B
Published: June 2004

Two different BALB/c anti-CBA (H-2k)monoclonal antibodies that bind to Kk and Dk antigens blocked Tc cell-mediated lysis of L929 (Kk, Dk) target cells, but with quite different specificity. One antibody (30R3) powerfully blocked Kk-specific lysis mediated by alloreactive or Kk-restricted Tc cells immune to ectromelia, Sendai, or influenza viruses. The other antibody (27R9) blocked these anti-Kk Tc cells much less than 30R3, but in contrast, 27R9 blocked anti-Dk lysis much more than 30R3. Most importantly, 27R9 strongly blocked Dk-restricted anti-influenza Tc cells, but did not significantly block Dk-restricted anti-Bebaru (BEB) lysis. This result indicated that different H-2 determinants coded in the D end of H-2k were recognized by influenza-and BEB-immune Tc cells. These determinants may be carried on two different molecules coded by the H-2D and H-2L loci, but other possibilities are not yet excluded.
Adaptive differentiation of murine lymphocytes. IV. (Responder × Nonresponder) F(1) T cells can be taught to preferentially help nonresponder,rather than responder, B cells
Authors: Katz DH , Katz LR , Bogowitz CA , Maurer PH
Published: June 2004

Responses to the synthetic terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) in the mouse are controlled by H-2-1inked Ir-GLTgenes. (Responder × nonresponder) F(1) hybrid mice, themselves phenotypic responders, can be primed with GLT to develop specific helper cells capable of interacting with 2,4-dinitrophenyl hapten (DNP)-primed F(1) B cells in response to DNP-GLT. Unlike the indiscriminant ability of F(1) helper T cells for conventional antigens (i.e. not Ir gene-controlled), which can help B cells of either parental type (as well as F(1)) equally well, GLT-primed F(1) T cells can only provide help under normal circumstances for B lymphocytes of responder parent origin; they are unable to communicate effectively with nonresponder parental B cells (1, and the present studies). The present studies reveal, however, that the induction of a parental cell-induced allogeneic effect during priming of F(1) mice to GLT actually dictates the direction of cooperating preference that will be displayed by such F(1) helper cells for B cells of one parental type or the other. Thus, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by parental BALB/c cells, develop into effective helpers for nonresponder A/J B cells, but fail to develop effective helpers for responder BALB/c B cells, and vice-versa. In contrast, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by either parental type, display significantly enhanced levels of helper activity for B cells derived from F(1) donors. These results are interpreted to reflect the existence of two interdependent events provoked by the allogeneic effect: one event augments the differentiation of GLT-specific helper T cells belonging to the subset corresponding to the opposite parental type; this would explain the development of increased helper activity provided to partner B cells of opposite parental type (as well as of F(1) origin). The second event, we postulate, involves the production of responses against the receptors which normally self-recognize native cell interaction determinants; this form of anti-idiotype response is restricted against self- recognizing receptors of the same parental type used for induction of the allogeneic effect, hence explaining diminished helper activity of such F(1) cells for partner B lymphocytes of corresponding parental type.
CBA/N X-linked B-cell defect prevents NZB B-cell hyperactivity in F1 mice.
Authors: Taurog J D , Moutsopoulos H M , Rosenberg Y J , Chused T M , Steinberg A D
Published: June 2004

NZB mice and their F1 hybrids produce excessive polyclonal IgM and autoantibodies of both IgM and IgG classes. CBA/N mice and CBA/N-mothered F1 males fail to make antibody to many T-independent antigens and have low levels of serum IgM; further, these mice lack a population of splenic B cells characterized by a low-to-intermediate density of surface IgM. We have studied male CBA/N, NZB, CBA/N X NZB, NZB X CBA/N, and CBA/J mice; female CBA/N X NZB mice; and males of several control crosses of NZB and CBA/N mice. We have found that the CBA/N X-linked defect of T-independent immune response is completely expressed in CBA/N X NZB mice. In marked contrast to NZB mice and to NZB mice and to NZB F1 hybrids bearing at least one normal X chromosome, the CBA/N X NZB males failed to respond to two T-independent antigens, had small numbers of splenic IgM-producing cells, barely detectable splenic IgM production, and splenic B-cell surface-Ig patterns resembling those of CBA/N mice. These data suggest that the NZB B-cell abnormality resulting in excessive IgM production occurs almost exclusively in that population of B cells affected by the CBA/N X chromome-linked defect. Preliminary studies suggest that CBA/N X chromosome retards the spontaneous development of anti-erythrocyte autoantibodies in CBA/N X NZB males. Castration, known to accelerate autoimmune disease in certain NZB F1 males, appears to have no influence on the immune functions examined in this study.
Genetic control of immunoregulatory circuits. Genes linked to the Ig locus govern communication between regulatory T-cell sets.
Authors: Eardley D D , Shen F W , Cantor H , Gershon R K
Published: June 2004

Antigen-stimulated Ly1:Qa1+ cells induce a nonimmune set of T-acceptor cells (surface phenotype Ly123+Qa1+) to participate in the generation of specific suppressive activity. The experiments reported here were designed to test the possibility that the interaction between T-inducer and T-acceptor cells might be governed by genes linked to the Ig locus. We find that inducer:acceptor interactions occur only if the inducer and acceptor T-cell sets are obtained from donor that are identical at the Ig locus and are independent of the Ig locus expressed on the B cells used for assay of T-helper activity. In addition, experiments using inducer and acceptor T cells from the congenic recombinant BAB. 14 strain show that T-T interactions are not governed by Ig-CH genes, per se. These data indicate that T-inducer: T-acceptor interactions are governed by Ig-linked genes that may control expression of VH-like structures on T cells, or control expression of as yet unidentified cell-surface molecules.
The requirement for adherent cells in the Fc fragment-induced proliferative response of murine spleen cells.
Authors: Morgan E L , Weigle W O
Published: June 2004

The proliferative response of mouse B lymphocytes induced by Fc fragments was found to be dependent upon an adherent cell population. The adherent cell is esterase positive, irradiation resistant, and not susceptible to lysis by anti-thymus serum and complement. The mechanism(s) by which Fc fragments induce B-cell proliferation could be the result of the interaction of Fc with both B cells and adherent cells or with adherent cells which then release factors that trigger the B cells to proliferate. Spleen cells from the C3H/HeJ mouse were shown to be unable to respond to Fc fragments. The addition of adherent cells from either C3H/St or C3H/HeN mice to adherent cell depleted C3H/HeJ cells enabled them to respond to Fc, indicating the defect was in the adherent cell population.
Regulation of macrophage and granulocyte proliferation. Specificities of prostaglandin E and lactoferrin
Authors: Pelus LM , Broxmeyer HE , Kurland JI , Moore MAS
Published: June 2004

Hemopoietic colony-forming cells committed to macrophage differentiation (M-CFC) are selectively and differentially inhibited by prostaglandin E (PGE). A hierarchy of sensitivity was observed among murine CFC stimulated by colony-stimulating factors (CSF) which differ in their ability to initiate proliferation of morphologically distinct colony types, or stimulated by CSF provided by macrophage feeder layers. Inhibition of macrophage colony formation to 50 percent levels occurred with PGE concentrations between 10(-8) and 10(-9) M, and was still evident at 10(-10) -10(-11) M PGE concentrations. The growth of mixed colonies containing both macrophages and neutrophils was less sensitive to the inhibitory effects of PGE, however, the monocytoid component of these colonies was reduced in the presence of PGE. Neutrophil progenitor cell proliferation was not influenced by PGE concentrations below 10(-6) M, regardless of time of addition of PGE, whereas clonal macrophage expansion, as well as clone size, was sensitive to inhibition by PGE when added as late as 3 d after culture initiation. Prostaglandin F(2α), was not inhibitory to colony formation. Experimental evidence for a selective role of macrophage PGE in the regulation of macrophage colony formation was directly provided by utilizing resident peritoneal macrophages as a source of CSF for bone marrow target cell overlays. Simultaneous morphological analysis of colonies proliferating in bilayer culture in response to increasing concentrations of macrophages, and direct measurements of PGE synthesized by an identical number of macrophages maintained in liquid culture demonstrate that a specific decline in macrophage colony formation occurs coincident with a linear increase in macrophage PGE synthesis. Inhibition of macrophage PGE synthesis by indomethacin results in the specific enhancement of macrophage colony formation. Furthermore, macrophage PGE synthesis is induced by CSF preparations with the selective capacity to differentially stimulate macrophage proliferation, but not by those which preferentially stimulate granulocyte colony formation. In comparison to the effects of PGE on M-CFC, polymorphonuclear granulocyte-derived lactoferrin (LF) reduces macrophage production of colony-stimulating activities for macrophage, mixed macrophage- neutrophil and neutrophil colony formation. The ability of LF to reduce macrophage PGE synthesis, presumably by decreasing CSF production, suggests that LF and PGE can interact in the control of macrophage and granulocyte proliferation.
Alloantigen-specific idiotype-bearing receptors on mouse T lymphocytes. I. Specificity characterization and genetic association with the heavy-chain IgG allotype.
Authors: Rubin B , Hertel-Wulff B , Kimura A
Published: June 2004

The present study describes the qualitative reactions of a xenogeneic anti-idiotype (Id) antiserum produced in a mouse-gamma-globulin-tolerant rabbit (5,936) against B6 anti-CBA IgG antibodies. The results showed that such an anti-Id antiserum reacts specifically against anti-H-2k antibodies and against H-2k alloantigen-activated T cells from the following pairs of congenic mice: B10 (H-2b) and B10.D2 (H-2d); and A.BY (H-2b) and A.SW (H-2s), but not against C3H.SW (H-2b) and C3H.OH (H-2o); and BALB/b (H-2b) and BALB/c (H-2d). CB 20 (BALB/c mice with the Ig-1b allotype) anti-CBA T blasts also express idiotypic determinants that react with rabbit 5,936 antiserum. Thus, positive reactions are obtained between rabbit 5,936 anti-Id antiserum and anti-H-2k IgG preparations and T blasts from mice carrying the Ig-1b or Ig-1e allotype, but not from mice carrying the Ig-1a allotype. These reactions are qualitatively independent of the H-2 genotype of the Id-producing mice. Such a finding strongly suggests that the Id-bearing receptor molecules on mouse T cells are coded for by genes that are associated with the Ig heavy-chain-linkage group and not to the mouse histocompatibility complex. Furthermore, the anti-Id antibodies studied react preferentially against anti-H-2k antibodies or T cells with specificity toward the IAk-region-associated serological specificities. Thus, genes associated with the Ig heavy-chain-linkage group seem to be structural genes for at least T-cell receptors with specificity for IA-region-coded membrane antigens.
Radioimmune analysis of an unexpected mouse allotype.
Authors: DeWitt C L , Bosma M J
Published: June 2004

We have used a radioimmune assay to confirm our earlier findings of an unexpected immunoglobulin allotype in Igb-congenic BALB/c mice. Although these mice were bred to exclude the IgG2a allotype of BALB/c (Ig-la), an Ig-la-like antigen was detected in the 7S Ig fraction of two (of five) pooled serum samples, it represented 0.1--0.3% of the total 7S protein and was indistinguishable from a reference Ig-la. The detection of putative Ig-la in Igb-congenic mice is inconsistent with the notion that allotypes are products of allelic structural genes. It appears rather that expression of Ig-la is controlled by allelic regulator genes and that its low and transient production in Igb-congenic mice results from incomplete negative regulation.
Reversal of nzb/nzw disease with total lymphoid irradiation.
Authors: Kotzin B L , Strober S
Published: June 2004

NZB/NZW mice spontaneously exhibit autoimmune disease similar to that seen in human systemic lupus erythematosus (SLE). We demonstrated that total lymphoid irradiation (TLI) reversed well expressed disease in 6-mo-old NZB/NZW females with a prolongation in survival, decrease in proteinuria, and decrease in anti-DNA antibodies as compared to control animals. Few side effects were observed in the treated group. TLI also prolonged survival in animals with advanced renal disease. These findings suggest that TLI may have application to the treatment of human SLE.
Lysis of measles virus-infected cells by the purified cytolytic alternative complement pathway and antibody.
Authors: Patrick Sissons J G , Schreiber R D , Perrin L H , Cooper N R , Müller-Eberhard H J , Oldstone M B
Published: June 2004

The dependence of antibody-and-complement-mediated lysis of virus-infected cells on the alternative pathway was examined utilizing the isolated cytolytic alternative pathway--a system consisting of the six purified proteins of the alternative pathway of activation (C3, factors B and D, beta 1H, C3b inactivator and properdin), and the five proteins of the membrane attack pathway (C5--9) of complement. HeLa cells acutely infected with measles virus were lysed by anti-viral IgG and the isolated cytolytic alternative pathway with an efficiency comparable to whole human serum. IgG and its F(ab')2 fragment were equally effective in inducing lysis by the isolated cytolytic alternative pathway, binding of approximately equal to 5 X 10(7) molecules per cell being required for 50% lysis; in contrast, no lysis occurred when equivalen or greater amounts of Fab' were bound to the virus-infected cell. Properdin was required for lysis. No lysis occurred if properdin was deleted from the isolated cytolytic alternative pathway, and lysis was diminished by 80% in properdin-depleted serum. Uptake of [125I]C3b from the isolated alternative pathway onto measles virus-infected cells occurred in the absence of properdin, but was accelerated in the presence of properdin. The 11 proteins of the isolated cytolytic alternative pathway are thus sufficient for lysis of measles virus-infected cells bearing anti-viral IgG or F(ab')2 without any other serum protein.
Failure of long surviving, passively enhanced kidney allografts to provoke T-dependent alloimmunity. II. Retransplantation of (AS X AUG)F1 kidneys from AS primary recipients into (AS X WF)F1 secondary hosts.
Authors: Welsh K I , Batchelor J R , Maynard A , Burgos H
Published: June 2004

Long surviving, passively enhanced (AS X AUG)F1 kidneys carried by AS recipients were retransplanted into (AS X WF)F1 second hosts. Acute graft rejection did not occur. Only one of six secondary recipients mounted a significant T-dependent IgG lymphocytotoxic antibody response. In all six, generation of cytotoxic T cells was markedly slower and depressed. These results are compatible with the hypothesis that kidney parenchyma, although carrying major histocompatibility complex specificity is able to induce T-independent but not T-dependent alloimmunity. A corollary is that passenger cells are responsible for exciting the T-dependent allimmune response normally observed after grafing. The practical difficulty of eliminating all T-dependent immunogenicity from (AS X AUG)F1 kidneys was emphasized by the observation that a 3-d residence in an intermediate AS recipient was insufficient time to prevent acute graft rejection after retransplantation.
Detection of a mediator derived from endotoxin-stimulated macrohpages that induces the acute phase serum amyloid A response in mice.
Authors: Sipe J D , Vogel S N , Ryan J L , McAdam K P , Rosenstreich D L
Published: June 2004

The mechanism by which LPS stimulates an acute phase serum amyloid A (SAA) response in C3H mice has been studied. A factor (SAA inducer) appears in the blood of C3H/HeN (lipopolysaccharide [LPS]-sensitive) mice approximately 1 h after administration of LPS, which, when passively administered, can induce C3H/HeJ mice to produce SAA although they are resistant to the LPS itself. SAA inducer has been detected in the culture medium of LPS treated C3H/HeN macrophages but not spleen cells. Thus, two stages in the induction of the acute phase SAA response are now recognized: a latent period of 2-3 h during which the SAA concentration remains at baseline values and in which SAA inducer appears, and the period of synthesis of SAA which lasts for approoximately 24 h past induction. It is proposed that a macrophage response to LPS is responsible for production of the serum mediator which induces SAA synthesis.
Augmentation of macrophage complement receptor function in vitro. I. Characterization of the cellular interactions required for the generation of a T-lymphocyte product that enhances macrophage complement receptor function.
Authors: Griffin J A , Griffin F M
Published: June 2004

The function of complement receptors of mouse peritoneal macrophages was converted in vitro from mediating only attachment of macrophage complement receptor function was achieved by treating freshly explanted macrophages with supernates from cultures containing T lymphocytes and appropriately triggered macrophages. Fc receptor-mediated phagocyctosis by macrophages was required for the production of active supernates, for neither ingestion via the cells' complement receptors nor ingestion via nonimmunologic means was a sufficient stimulus for the macrophages' participation in the generation of supernatant activity. Fc receptor-triggered macrophages interacted by a contact dependent, but histocompatibility independent, mechanism with T lymphocytes, thereby signalling the lymphocytes to elaborate the active product. The possible significance of enhanced macrophage complement receptor function in inflammation, host defense against microbial pathogens, immune complex disease, and neoplasia is discussed.
Thymic reconstitution of nude F1 mice with one or both parental thymus grafts
Authors: Zinkernagel RM , Althage A , Callahan G
Published: June 2004

Thymus-derived lymphocytes (T cells) have two outstanding characteristics that distinguish them from other lymphocytes: (a) they express two specificities, one for self-antigens, the major transplantation antigens (H) coded by the major histocompatibility gene complex (MHC), and a second specificity for foreign antigenic determinants. (b) T cells must undergo differentiation or maturation in the thymus (1, 2). Apparently, an important step in T-cell differentiation in the thymus is the selection of T-cells' restriction specificity for self-H. This interpretation stems from experiments with chimeras formed by lethally irradiating parental type mice and reconstituting them with F(1) stem cells: the maturing F(1) T cells expressed predominantly the restriction specificities for the recipient parental MHC type (3-8). Alternatively, adult F(1) mice that were thymectomized, lethally irradiated, reconstituted with bone marrow, and then engrafted with a parental thymus had T cells that were restricted predominantly to the thymus donors' H-2 (4-8).

The present study first extends these observations to nude mice that are born without a thymus and therefore do not develop functional T cells and second, attempts to study the possibility that suppression may be responsible for the apparent influence of the radioresistant portion of the thymus on T- cell restriction specificities.

We tested the immunocompetence and restriction specificities expressed by lymphocytes from F(1) nude mice reconstituted with both parental thymus grafts; our expectation was that suppression of the expression of T-cell restriction specificity should result either in complete immunoincompetence or emergence of only one of the two possible sets of restriction specificities. Nude F(1)mice that simultaneously received thymus gratis from both parents developed spleen cells restricted to both parental H-2 types. These results are compatible with the idea that the thymus' influence on T- cell restriction is via positive selection rather than by suppression.
Intracellular localization of Rickettsia tsutsugamushi in polymorphonuclear leukocytes.
Authors: Rikihisa Y , Ito S
Published: June 2004

Rickettsia tsutsugamushi (Gilliam strain) was serially propagated in BHK-21 cell cultures and incubated with guinea pig peritoneal polymorphonuclear leukocytes to study the ultrastructural features of rickettsial uptake and entry into the leukocytes. Significant numbers of rickettsiae were phagocytized selectively by these leukocytes within 30 min. About one-half of these rickettsiae remained sequestered in phagosomes but the other one-half were free from the phagosome and localized directly in the polymorphonuclear leukocyte cytoplasm. Various stages of rickettsial release from the phagosomes were observed. Once free within the polymorphonuclear leukocyte cytoplasm, the rickettsiae were preferentially localized in the glycogen-packed areas which are devoid of lysosomes and other cytoplasmic organelles. This study indicates that rickettsiae phagocytized by polymorphonuclear leukocytes can escape from the phagosome into the cytoplasm.
Lymphoid function in F1 leads to parent chimeras: lack of evidence for adaptive differentiation of B cells or antigen-presenting cells.
Authors: Sprent J , Bruce J
Published: June 2004

Information was sought on whether B cells undergo abnormal differentiation in F1 leads to parent chimeras (irradiated parental-strain mice reconstituted with F1-hybrid bone marrow cells). As assessed by collaborative responses to sheep erythrocytes in vivo, three different types of T cells restricted to interaction with strain a H-2 determinants were shown to collaborate as effectively with heterologous F1 leads to b chimera B cells as with homologous F1 leads to a chimera B cells. This applied to both primed and unprimed B cells, to IgM- and IgG-antibody formation and to production of Ig allotype. Thus, unlike T cells, B cells from F1 leads to parent chimeras behaved indistinguishably from normal F1 B cells. F1 leads to parent chimeras were also examined for their capacity to present antigen to normal F1 T cells in vivo. The results suggested that the antigen-presenting cells in these chimeras were no different than in normal F1 mice. Collectively these data imply that, at least in the situation studied, raising F1 stem cells in a parental-strain environment has a marked effect on T-cell specificity but does not discernably influence the differentiation of B cells or macrophage-like cells.