bluuebunny/crossref_metadata_2025_split huggingface dataset:
INTERGROUP PHAGE REACTIONS AND TRANSDUCTION BETWEEN GROUP C AND GROUP A STREPTOCOCCI
Authors: Wannamaker Lewis W. , Almquist Susan , Skjold Stephen 
Published: June 2004

In a study of intergroup reactions, four virulent Group A streptococcal phages were found to form plaques in high titer on lawns prepared from a number of Group C streptococcal strains. Whether the phages were propagated on the homologous (Group A) strain or a heterologous (Group C) strain did not appear to influence consistently the plaque-forming efficiency on lawns prepared from a homologous (Group A) or a heterologous (Group C) strain or to alter significantly the percent of Group C strains which showed plaque formation.
Considerable variability was found in the ability of temperate phages to lyse strains of a heterologous group. A single Group C indicator strain was lysed by a high percentage of freshly induced temperate Group A phages. A single temperate Group C phage lysed a significant proportion of Group A strains when freshly induced or when propagated on a Group A strain.
Intragroup transduction of streptomycin resistance was demonstrated between Group C strains. Intergroup transduction of streptomycin resistance and also bacitracin resistance was achieved between Group C and Group A streptococci. These observations provide evidence that Group A streptococci can serve as recipients in intergroup transmission of genetic information.
Ultraviolet irradiation of the transducing lysate and lowering the propagation temperature of the transducing lysate increased the frequency of transduction in both the intragroup and intergroup transduction systems.
REQUIREMENTS FOR PROLONGED SUPPRESSION OF AN IDIOTYPIC SPECIFICITY IN ADULT MICE
Authors: Pawlak Laura L. , Hart David A. , Nisonoff Alfred 
Published: June 2004

The appearance of an idiotypic specificity, present in anti-p-azophenylarsonate (anti-Ar) antibodies of all immunized A/J mice, ran be suppressed in adult mice by prior administration of an IgG fraction of rabbit antiidiotypic (anti-D) antiserum; anti-Ar antibodies arise but are of different idiotype. Prolonged suppression was observed in earlier experiments, but antigen was first administered to adult mice only 2 wk or 9 wk after anti-D antibodies; subsequent escape from idiotypic suppression could have been masked by the capture of antigen by large numbers of memory cells having receptors of a different idiotype. In the present experiments antigen was first administered at intervals up to 22 wk after the antiidiotypic antibody. Suppression was maintained for 6 wk in all mice and for 5 mo in about half the mice tested. It thus appears that suppression of idiotype is less reversible if antigen is administered soon after the antiidiotypic antibody. The data suggest that escape from suppression is attributable to the generation of new precursor cells rather than to reactivation of suppressed cells.
The minimum dosage of antiidiotypic IgG required for effective suppression was about 2 mg. The subcutaneous or intraperitoneal routes of inoculation of antiidiotypic IgG were equally effective. When antiidiotypic antibody was administered 3 days after antigen no suppressive effects were observed. There was partial suppression when antiidiotypic antibody was injected on the same day as the antigen. Fab' and F(ab')2 fragments of antiidiotypic IgG had no suppressive effect. Quantitative measurements revealed no significant differences among control and suppressed mice with respect to total concentration of precipitable anti-Ar antibodies produced.
IMMUNOGLOBULIN AND GLUCOSE-6-PHOSPHATE DEHYDROGENASE AS MARKERS OF CELLULAR ORIGIN IN BURKITT LYMPHOMA
Authors: Fialkow Philip J. , Klein Eva , Klein George , Clifford Peter , Singh Surjit 
Published: June 2004

Two independent marker systems, G-6-PD isoenzymes and cell membrane-associated IgM, were used to trace the cellular origin of Burkitt lymphoma. Application of the G-6-PD system is dependent upon the fact that, in accordance with inactivity of one X chromosome in each somatic cell, females heterozygous for the usual B gene (GdB) at the X-linked G-6-PD locus and the variant allele GdA (or GdA-) have two types of cells. GdB is active in one cell population, which consequently produces B type enzyme; in the other population GdA is active, producing the variant A enzyme. Therefore, tumors with a clonal origin in a GdB/GdA heterozygote should exhibit only one enzyme type (B or A) whereas those with multicellular origin may show both A and B enzymes. Utilization of the immunoglobulin system is based upon the supposition that in lymphoid neoplasms with clonal origin either all or none of the tumor cells should have surface-associated IgM and κ-reactivities.
33 of 34 relatively homogeneous (with respect to content of neoplastic cells) individual Burkitt tumors from 19 G-6-PD heterozygotes had single enzyme phenotypes. Similarly, of 95 tumors tested, 92 consisted essentially of IgM(+) or (-) cells. Two neoplasms could not be definitely classified and one tumor had two cell populations. These data suggest a clonal origin for most Burkitt tumors, but the one neoplasm with a double G-6-PD phenotype (A/B) and the one tumor that had two populations of cells with respect to surface IgM, could have originated from multiple cells.
G-6-PD was determined in each of two tumors from seven heterozygotes and in all cases both tumors had the same single enzyme phenotype. Surface-associated IgM was tested in four tumors from one patient, three from another, and in two neoplasms from 11 patients. With one exception, all tumors from the same patient were concordant with respect to IgM. These findings suggest that the entire disease has a clonal origin, i.e., it emerges at one focus and then spreads to other parts of the body.
Cells from 36 recurrent neoplasms were typed for G-6-PD (in heterozygotes) and/or IgM. In one previously reported patient, initial and recurrent tumors were discordant for G-6-PD. Two other patients had IgM phenotypes in recurrences that were discordant with those found in their initial tumors. Phenotypes from three of nine relapses which occurred after 5 mo were discordant for G-6-PD or IgM but no discordance was detected among 27 earlier recurrences. Thus, some "late" recurrences may be due to emergence of "new" maligant cell lines whereas most early relapses are due to reemergence of the original malignant clones.
The probable unicellular origin of Burkitt lymphoma and the findings in tumor recurrences are discussed in terms of the disease's putative viral etiology.
THE MEMBRANE ATTACK MECHANISM OF COMPLEMENT
Authors: Kolb William P. , Haxby James A. , Arroyave Carlos M. , Müller-Eberhard Hans J. 
Published: June 2004

Reversible interactions in free solution were demonstrated to occur (a) between C5 and C8, (b) between C5, 6, 7 and C8, and (c) between C8 and C9. No interaction was observed between C8 and C6 or C7 and between C9 and C5, 6, 7. Interactions between C8 and C9 were enhanced at lowered ionic strength (0.05) and a molar excess of C8 over C9. Complex formation was independent of pH over the range of 6.5–8.5. Under optimal conditions the C8, 9 complex had a sedimentation coefficient of 10.2–10.6S, while native C8 and C9 sedimented at 8.5 and 4.8S, respectively. Specificity and reversibility of these interactions were established.
In spite of the limited number of interactions observed, all five of the native proteins of the membrane attack mechanism interacted to form an association product that sedimented at 10.8–11.2S. Demonstration of this product in free solution supports the concept that C5-9 on acquisition of cytolytic activity assemble into a stable multimolecular complex.
PROMOTION OF REPLICATION IN LYMPHOID CELLS BY SPECIFIC THIOLS AND DISULFIDES IN VITRO
Authors: Broome J. D. , Jeng M. W. 
Published: June 2004

Numerous lines of mouse lymphoid tumors (13 of 22 tested) showed, with increased sensitivity, a property of normal mouse splenic lymphocytes, the potential for growth promotion in vitro by specific thiols added to standard culture media. For lymphoma L1210 (V), structure activity relationships were examined; 9 of 30 thiols promoted growth; the most active was α-thioglycerol, effective at 0.2 µM. Thiols became oxidized under conditions of tissue culture and had half-lives of less than 8 h. Disulfides of active thiols promoted growth of lymphoma cells.
The mitogenic response of splenic lymphocytes to lectins was increased by thiols-disulfides which promoted the growth of lymphoma cells, but the response varied with the mitogen preparation used and under some conditions thiols-disulfides were inhibitory.
LEUKEMIA-ASSOCIATED TRANSPLANTATION ANTIGENS RELATED TO MURINE LEUKEMIA VIRUS
Authors: Sato H. , Boyse E. A. , Aoki T. , Iritani C. , Old L. J. 
Published: June 2004

Two BALB radiation leukemias are strongly rejected by hybrids of BALB with certain other mouse strains, although BALB mice themselves exhibit no detectable resistance whatever. Hybrids immunized with progressively increased inocula are resistant to 200 x 106 or more leukemia cells; their serum is cytotoxic for the leukemia cells in vitro and protects BALB mice against challenge with these BALB leukemias. The antigenic system thus identified has been named X.1.
In (BALB x B6) hybrids the major determinant of resistance was shown to be a B6 gene in the K region of H-2. This is likely to be the Rgv-1 (Resistance to gross virus) locus of Lilly, which may thus be identified in this case as an Ir (Immune response) allele conferring ability to respond to X.1 antigen on MuLV and leukemia cells, and so responsible for production of X.1 antibody and the rejection of X.1+ leukemia cells by hybrid mice.
Immunoelectron microscopy with X.1 antiserum (from immunized hybrids) shows labeling both on the cell surface and on virions produced by the leukemia cells. It is not known whether X.1 comprises only one or more than one antigen.
Three radiation-induced BALB leukemias, one A strain radiation-induced leukemia, and 15/15 AKR primary spontaneous leukemias were typed X.1+ by the cytotoxicity test. Several other leukemias, including one induced by passage A Gross virus and one long-transplanted AKR ascites leukemia carried in (B6 x AKR)F1 hybrids, were X.1-. Normal mice of strains with a high incidence of leukemia and one other strain (129) express X.1 antigen, but evidently in amounts too small for certain detection in vitro; by the method of absorption in vivo, however, these strains could be typed X.1+ and other strains X.1-.
We ascribe the X.1 antigen system tentatively to a sub-type of MuLV that is not passage A Gross virus and is probably not the dominant sub-type in strains with a high incidence of leukemia.
After repeated passage in hybrids, one of the BALB leukemias became relatively resistant to rejection by the hybrid, partially lost its sensitivity to X.1 antiserum in vitro, and in electron micrographs was seen to produce fewer virions.
The serum of untreated (BALB x B6) hybrids often contains cytotoxic antibody against leukemia cells, some of it probably anti-X.1. But another commonly occurring antibody, which is cytotoxic for C57BL leukemia EL4, appears to belong to another (undefined) system.
CYTOSTATIC ELIMINATION OF SYNGENEIC RAT TUMOR CELLS IN VITRO BY NONSPECIFICALLY ACTIVATED MACROPHAGES
Authors: Keller R. 
Published: June 2004

Syngeneic tumor cell lines induced in inbred DA rats by polyoma virus, dimethylbenzanthracene, or methylcholanthrene were interacted in vitro with syngeneic effector cells. Glycogen-induced peritoneal exudate cells, predominantly polymorphonuclear leukocytes, and proteose peptone-induced peritoneal cells, principally macrophages, were the effector cells employed. Activated, nonimmune macrophages or exudative polymorphonuclear leukocytes produced pronounced morphological changes in syngeneic tumor cells as evidenced by a substantial reduction in tumor cell numbers and appearance of shrunken cells, even though there was no increase in cell debris. Polymorphonuclear leukocytes exerted a generally similar but quantitatively much diminished effect. These effector cells constantly produced a decrease in the incorporation by tumor cells of DNA precursors such as [3H]thymidine and of RNA precursors such as [3H]uridine. In this regard, the effector cells were quite refractory to high doses of X-irradiation.
Interaction of target cells with activated, nonimmune macrophages yielded low but consistent signs of cytotoxicity, whereas polymorphonuclear leukocytes gave no such effects. Elimination of functional macrophages by silica, an agent specifically toxic for macrophages, resulted in unrestricted tumor cell proliferation despite continued generation of cytotoxicity. Accordingly, cytostatic mechanisms appear to play a predominant role in the elimination of tumor cells by nonimmune phagocytes. Evidence from a variety of experimental approaches suggest that the cytostatic effect is dependent on cell-to-cell contact.
ALLOTYPE SUPPRESSION IN THE RABBIT
Authors: Harrison Michael R. , Mage Rose G. 
Published: June 2004

The ability to distinguish immunoglobulin (Ig) of paternal allotype both on lymphocyte membranes and in the serum of neonatal b4b5 heterozygous rabbits has allowed us to study the postnatal ontogeny of cells bearing endogenously synthesized Ig that could not have been derived from the mother. In normal b4b5 rabbits, such endogenously synthesized Ig of paternal allotype is present on the membranes of bone marrow-derived (B) lymphocytes from birth, but does not appear as detectable circulating Ig until ∼2 wk of age.
In the neonate, cells bearing the paternal allotype are potential targets for the induction of chronic allotype suppression. Within 24 h of exposure to anti-allotype antisera in vivo, Ig of the suppressed paternal allotype is no longer detectable on the surface of neonatal lymphoid cells. Further, this lymphocyte membrane Ig is eliminated and not simply masked by the suppressing antibodies. Finally, cells bearing the suppressed allotype are deleted from all lymphoid organs for the duration of total allotype suppression, and reappear first in bone marrow and peripheral blood at the time of spontaneous escape from suppression.
OLIGOMERIC IGA: THE MAJOR COMPONENT OF THE IN VITRO PRIMARY RESPONSE OF MOUSE SPLEEN FRAGMENTS
Authors: Nakamura Ichiro , Ray Alex , Mäkelä O. 
Published: June 2004

The primary antibody response elicited from mouse spleen explants by conjugates of the 3-nitro-5-iodo-4-hydroxyphenylacetic acid (NIP) hapten consisted mostly of the IgA class. Poly-L-lysine, pneumococcal polysaccharide Type SIII, keyhole limpet hemocyanin, and sheep erythrocytes were effective carriers in this system, whereas chicken globulin was not. The anti-NIP response against all of the immunogenic conjugates was detectable in culture media 4 days after explantation and immunization, and reached peak titers by 8–10 days. IgA was identified by sucrose gradient velocity centrifugation in conjunction with the use of a class-specific antiserum. The media collected at 4 days contained low titers of IgM antibody, whereas the peak response at 8 days consisted almost entirely of IgA.
The primary response IgA secreted by the spleen fragments was characterized as polymeric by its sedimentation rate through a sucrose gradient, and as polyvalent by its drastically greater avidity for NIP14BSA than for free NIP-aminocaproic acid. Its haptenated phage-inactivating activity was abolished by treatment with 0.1 M 2-mercaptoethanol.
These experiments indicate that precursor cells existing in the spleen before primary immunization can give rise to production of polymeric IgA.
FIBRINOLYSIS ASSOCIATED WITH ONCOGENIC TRANSFORMATION
Authors: Ossowski L. , Quigley J. P. , Kellerman G. M. , Reich E. 
Published: June 2004

Fetal bovine and dog serum were selectively freed of plasminogen by affinity chromatography. The resulting serum as well as native and reconstituted serum (obtained by the addition of purified plasminogen to the plasminogen-depleted serum) were used to examine the role of plasminogen in (a) growth of normal and SV-40-transformed hamster embryo fibroblasts in liquid medium, (b) growth of SV-40-transformed hamster embryo fibroblasts in soft agar, (c) aggregation — a characteristic morphological change of SV-40-transformed hamster cells, and (d) migration of SV-40-transformed and control 3T3 cells from a monolayer into a "wound."
The results demonstrated that exponential growth of both normal and transformed cells in liquid medium proceeded at the same rate in the presence or absence of plasminogen. In contrast, removal of plasminogen markedly depressed the plating efficiency of transformed cells in soft agar, eliminated their characteristic aggregation, and substantially reduced the extent of migration. The role of plasminogen and its activation in oncogenic transformation is discussed.
ANATOMICAL DISTRIBUTION OF T AND B LYMPHOCYTES IN THE RAT
Authors: Goldschneider Irving , McGregor D. D. 
Published: June 2004

A method is described whereby antisera raised in rabbits to rat thoracic duct lymphocytes were made specific for the plasma membrane antigens of T and B lymphocytes. These lymphocyte-specific antisera were used in immunofluorescence assays to study the distribution of B and T cells in lymphocyte containing tissues and body fluids of the rat.
Rabbit antirat B-cell serum (ALSB) reacted selectively with the surfaces of lymphocytes in the lymphoid follicles of lymph node cortex and in the follicles and marginal zones of splenic white pulp, but not with the surfaces of germinal center cells or plasma cells. An identical pattern of fluorescent staining was obtained with rabbit antirat Ig serum. It was shown by blocking, absorption, and immunoprecipitation studies that ALSB was composed in large part of antibodies to rat Ig, but that it contained antibodies to other B-cell antigens as well.
Rabbit antirat T-cell serum (ALST) reacted selectively with the surfaces of lymphocytes in the paracortex of lymph node and in the periarteriolar sheath of spleen, and with thymocytes. ALST did not display anti-Ig activity.
ALST reacted with approximately 100% thymocytes and with 90% thoracic duct, 80% lymph node, 60% blood, 50% spleen, and 10% bone marrow lymphocytes in suspensions of cells from these sources. ALSB reacted with the remainder of the lymphocytes in the suspensions, except for bone marrow in which only 59% of lymphocytes had detectable B- or T-cell surface antigens.
The population of T lymphocytes in rat bone marrow was depleted by drainage of lymphocytes from a thoracic duct fistula, thereby establishing their membership in the pool of recirculating T cells. Approximately 14% of lymphocytes issuing from the thoracic duct of TxBM donors reacted with ALST. The presence in these animals of a small number of T cells, calculated to be approximately 2% of the normal value, may account for the limited capacity of TxBM rats to respond to antigens that induce a cell-mediated immune response.
EFFECT OF RECENT ANTIGEN PRIMING ON ADOPTIVE IMMUNE RESPONSES
Authors: Sprent J. , Miller J. F. A. P. 
Published: June 2004

When thoracic duct lymphocytes (TDL) or mesenteric lymph node (MLN) cells from mice primed 1 day before with either sheep erythrocytes (SRC) or horse erythrocytes (HRC) were transferred together with both SRC and HRC to irradiated mice, antibody responses measured 7 days later could not be detected to the priming antigen but were high to the other antigen. Furthermore, this unresponsiveness of TDL and MLN to the priming antigen could not be abrogated by delaying antigen challenge of the transferred cells for 1–2 wk.
Previous work had shown that short-term priming with antigen also induced specific unresponsiveness in spleen cells on adoptive transfer. Unresponsiveness in these cells, however, was only of temporary duration, full recovery in the reactivity of the cells being observed when challenge with the priming antigen on transfer was delayed for 5 or more days. Since the present work showed that such recovery from initial unresponsiveness on transfer was unique to spleen cells and did not apply to TDL or MLN, it appeared that different mechanisms were responsible for the unresponsiveness in the three populations. It is proposed that the unresponsiveness detected in TDL and MLN cells in the present study resulted from a deficiency of antigen-reactive cells, these cells having been recruited to the spleen, i.e., a region of antigen concentration. This concept of antigen-induced selective recruitment of circulating lymphocytes was supported by evidence that 51Cr-labeled heterologous erythrocytes indeed localized largely in the spleen after intravenous injection but not in MLN.
CYTOTOXIC IMMUNE CELLS WITH SPECIFICITY FOR DEFINED SOLUBLE ANTIGENS
Authors: Schirrmacher Volker , Rubin Bent , Pross Hugh , Wigzell Hans 
Published: June 2004

Spleen cells from mice immunized against ovalbumin (OA) or dinitrophenylated mouse serum albumin (DM) were found to be specifically cytotoxic in vitro towards target cells (chicken red blood cells) coated with these antigens. Inhibition of specific cytotoxicity was observed when free soluble antigen was added to the incubation mixtures. DM-immune cell cytotoxicity could be specifically and completely inhibited by DNP-lysine and was thus shown to be hapten specific. Complete and specific inhibition was also observed for OA-immune cell cytotoxicity using OA as inhibitor, but compared with the inhibition curves obtained with DNP-lysine, the OA cytotoxicity inhibition curves were shifted by a factor of about one hundred towards lower molar inhibitor concentrations. Very similar results were observed when the serum antibodies of DM- and OA-immune animals were analyzed by passive hemagglutination inhibition. With increasing time after immunization, both cytotoxicity inhibition curves and agglutination inhibition curves, shifted to lower antigen or hapten concentrations.
Specific cytotoxicity against antigen-coated target cells was induced in nonimmune spleen cells (a) by serum from immune animals, and (b) by supernatants from in vitro immune cell cultures. In both instances, the factor which induced antigen-specific cytotoxic activity could be absorbed on anti-mouse Ig columns, thus demonstrating its immunoglobulin nature. The ability of target cell bound antibodies to induce cytotoxicity in nonimmune spleen cells was restricted to the 7S antibody class.
SEGMENTAL RESPONSE OF THE MACROPHAGE PLASMA MEMBRANE TO A PHAGOCYTIC STIMULUS
Authors: Griffin Frank M. , Silverstein Samuel C. 
Published: June 2004

A method of attaching mouse RBCs to mouse macrophages is described. Both cell types were coated with rabbit anti-mouse macrophage F(ab')2, and cross-linkage of cells was effected with sheep F(ab')2 directed against rabbit F(ab')2. 98% of macrophages attached an average of 11 RBCs each. Attachment occurred at 37°C and was stable for at least 4 h. Less than 0.1% of macrophages ingested RBCs under these conditions.
Latex particles and opsonized pneumococci were ingested as avidly by RBC-coated macrophages as by native macrophages. Ingestion of these particles did not prompt ingestion of attached RBCs. When anti-RBC IgG was added, however, over 90% of macrophages ingested an average of six RBCs each. Thus, ingestion of one particle does not trigger generalized phagocytosis of all particles attached to the cell's plasma membrane, and the phagocytic stimulus is confined to the segment of the cell's plasma membrane immediately adjacent to the particle being ingested.