bluuebunny/crossref_metadata_2025_split huggingface dataset:
INFLUENCE OF DIETARY POTASSIUM AND SODIUM/POTASSIUM MOLAR RATIOS ON THE DEVELOPMENT OF SALT HYPERTENSION
Authors: Dahl Lewis K. , Leitl George , Heine Martha 
Published: June 2004

Among genetically hypertension-prone rats, dietary sodium (chloride) was demonstrably hypertensinogenic and potassium (chloride) antihypertensinogenic.
On diets containing the same NaCl but different KCl concentrations, mean blood pressure was greater in rats receiving less dietary potassium, i.e., diets with a higher Na/K molar ratio.
On diets with different absolute concentrations of NaCl and KCl, but the same Na/K molar ratios, rats on the higher absolute NaCl intakes had the higher blood pressures.
On diets with different absolute concentrations of NaCl and KCl, and different Na/K molar ratios, a group on a lower absolute NaCl intake but with a higher Na/K ratio could have more hypertension than a group on a higher absolute NaCl intake but with a lower Na/K ratio.
At equivalent molar ratios, the respective effects of these two ions on blood pressure were dominated by that of sodium. It was concluded that the dietary Na/K molar ratio can be an important determinant for the severity, or even development, of salt-induced hypertension.
The mechanism of the moderating effect of potassium on sodium-induced hypertension was unclear.
THE ALLOGENEIC EFFECT IN INBRED MICE
Authors: Katz David H. , Osborne David P. 
Published: June 2004

Experimental conditions have been established for the elicitation of an allogeneic effect on the adoptive transfer secondary anti-2,4-dinitrophenyl (DNP) antibody response in mice. Thus, spleen cells from DNP-keyhole limpet hemocyanin (KLH)-primed mice manifest good secondary anti-DNP responses to a challenge with DNP-KLH, but not with DNP-bovine gamma globulin (BGG), after adoptive transfer to irradiated syngeneic recipients. However, a good adoptive transfer secondary anti-DNP response of such cells can be elicited with DNP-BGG when a second transfer of allogeneic lymphoid cells, in appropriate numbers, is carried out 24 hr before secondary challenge. The advantage to this system is that the DNP-primed cell population as well as the population of allogeneic lymphoid cells are accessible to experimental manipulation such that the T lymphocytes of one or the other can be removed.
Utilizing this model, we have established that the allogeneic effect on antibody production can operate on a population of primed B lymphocytes which have been depleted of their isologous T lymphocytes by in vitro incubation with anti-θ serum plus complement. The potential cellular interactions involved in the mechanism of this phenomenon are considered and discussed in detail.
THE MIGRATION OF LYMPHOCYTES ACROSS THE VASCULAR ENDOTHELIUM IN LYMPHOID TISSUE
Authors: Schoefl G. I. ,   With an Appendix by R. E. Miles
Published: June 2004

An electron microscope study was made of the mode of lymphocyte migration across the endothelial layer of venules in the Peyer's patches of mice and rats. Single and serial sections were examined.
Of a total of about 800 lymphocytes observed in single sections, 91% were located between endothelial cells and 9% were surrounded by endothelial cytoplasm in the particular plane of section. 62% of the lymphocytes occurred in groups of two or more. In long sequences of serial sections through 21 endothelial cells, all lymphocytes were located external to the endothelial cells though some appeared "internal" at certain levels of sectioning.
The probability that a lymphocyte which appears to be surrounded by endothelial cell cytoplasm actually lies within the cell was analyzed with a mathematical model derived from data obtained from single sections. The results of this analysis suggested that at least 93–99% of lymphocytes (within 90% limits of confidence) take an intercellular path in their migration from blood to lymph.
It is concluded that lymphocytes migrate across the vascular endothelium by insinuating themselves between endothelial cells and not by passing through them. Rather than constituting an increased barrier to cell migration, the unusual height of the endothelial cells in these vessels is interpreted to be a special adaptation which allows sustained cell traffic without excessive fluid loss taking place concomitantly.
BLOOD MICROCIRCULATION IN THE LYMPH NODE DURING THE PRIMARY IMMUNE RESPONSE
Authors: Herman Peter G. , Yamamoto Itaru , Mellins Harry Z. 
Published: June 2004

Microangiography performed after total blood replacement with contrast material provided complete visualization of the vascular structures of the lymph node.
Starting of the 2nd day, there is capillary redistribution throughout the cortex of the lymph node. The previously rather avascular nodules dissolve, and the cortical lymphoid tissue becomes uniformly vascular. Beginning on the 2nd day and reaching its peak on the 5th day, there is a significant increase in diameter and density of the subcapsular and medullary cord capillaries. 15 days after the antigenic stimulus, the appearance of the microvasculature returns to normal.
The postcapillary venules (the microvascular structures which follow the capillaries) are widely distributed throughout. Histologically, only a fraction of these venules have a high endothelial lining (HE venules). Therefore, it is suggested that among the postcapillary venules, those with high endothelial lining should be specifically denoted. Great individual variation in the number of HE venules was observed, and no correlation with the timing of the immune response could be established.
Whether the microvascular changes described lead to cellular change or are mere expressions of it cannot definitely be stated. However, the significant hypervascularity along the intranodal lymph pathways and the diffuse, even redistribution of the capillaries and postcapillary structures could greatly facilitate the humoral and cellular exchange between the circulating blood, the circulating lymph, and the tissues of the lymph node.
INITIATION OF ANTIBODY RESPONSES BY DIFFERENT CLASSES OF LYMPHOCYTES
Authors: Strober Samuel 
Published: June 2004

The life-span and migratory characteristics of rat thoracic duct cells which initiate the adoptive primary and secondary antibody response to diphtheria toxoid (DT) and horse spleen ferritin (HSF) were investigated. The experimental results show that thoracic duct lymphocytes from normal (unimmunized) donors are able to restore the adoptive response of irradiated hosts to HSF. Thoracic duct cells passaged through an intermediate host (intravenous injection and subsequent collection in the thoracic duct lymph) showed a marked reduction in their restorative action as compared with unpassaged cells. In addition, the restorative action of cells from donors treated with thymidine-3H for 48 hr before cannulation of the thoracic duct was markedly decreased. This indicates that a population of lymphocytes involved in the adoptive primary response is unable to recirculate from the blood to the lymph and is turning over rapidly (short lived). The nonrecirculating, short-lived lymphocytes are proably "B" cells, since a combination of spleen cells from neonatally thymectomized rats and passaged or thymidine-3H-treated cells restores a vigorous response to HSF.
On the other hand, passaged or thymidine-3H-treated thoracic duct cells from donors immunized to DT or HSF are able to restore a vigorous adoptive secondary antibody response. Experiments with the hapten-protein conjugate, DNP-DT, show that the majority of both helper ("T") and precursor ("B") cells are able to recirculate and are slowly turning over (long lived). The findings suggest that T lymphocytes involved in both the primary and secondary antibody response are recirculating, long-lived cells. However, B lymphocytes involved in the primary response are nonrecirculating, short-lived cells ("B1" cells) which undergo a fundamental physiological change to recirculating, long-lived cells ("B2" cells) involved in the secondary antibody response.
LIGAND-INDUCED MOVEMENT OF LYMPHOCYTE MEMBRANE MACROMOLECITLES
Authors: Karnovsky Morris J. , Unanue Emil R. , Leventhal Monika 
Published: June 2004

Anti-immunoglobulin (Ig) coupled to ferritin or hemocyanin was used to map the distribution of Ig molecules on lymphocytes derived from bone marrow (B lymphocytes) by freeze-etching. The labeled anti-Ig was distributed all over the membrane in the form of random interconnected patches forming a lacy, continuous network. This was the pattern of lymphocytes labeled at 4°C with the anti-Ig. After warming at 37°C, the labeled molecules concentrated into a single area of the cell (forming the cap) and were rapidly internalized in small vesicles Freeze-etching showed close packing of the labeled molecules in the cap area. There was evidence that in the cap area the Ig molecules were exfoliated from the plane of the membrane, suggesting that the Ig may be superficial to the bilipid layer, or weakly anchored to the membrane.
Similar studies were made using antibodies to histocompatibility antigens. Thymocytes were labeled with anti-H-2 and ferritin anti-Ig at 4°C. Freeze-etching showed large patches scattered over the membrane and separated from each other by several thousand angstroms. This distribution may, in part, explain why H-2 antigens do not readily form a cap; the large patches are beyond the reach of even a double ligand (sandwich) reaction.
The antigens that reacted with heterologous anti-lymphocyte globulin (ALG) were found in small noninterconnected clusters a few hundred angstroms apart. Such clusters presumably cannot be linked by a single antibody but can by a sandwich (ligand to ligand-antigen) reaction. In previous studies it was found that ALG antigens form a cap only after a sandwich reaction. Finally, the receptors for concanavalin A (Con A) were found in a lacy, irregular interconnected, random network. The spatial distribution of these moieties on the membrane may, in great part, determine their movement after reaction with one or two ligands.
HISTOCOMPATIBILITY STUDIES IN A CLOSELY BRED COLONY OF DOGS
Authors: Rapaport F. T. , Watanabe K. , Cannon F. D. , Mollen N. , Blumenstock D. , Ferrebee J. W. 
Published: June 2004

17 Cooperstown beagles of known DL-A genotypes were exposed to supralethal total body irradiation and received a bone marrow allograft from a DL-A-identical donor; 11 littermate and 6 nonlittermate donor-recipient pairs were studied. The recipients are surviving uneventfully for 315, 364, 424, 440, 531, 531, 584, 605, 625, 635, and 649 days in the littermate group and for 211, 279, 280, 368, 479, and 480 days in the nonlittermate group.
The radiation chimeras underwent bilateral nephrectomy and received a kidney allograft obtained from their respective marrow donor within 43–120 days after bone marrow transplantation. The renal allografts are surviving for 191, 200, 221, 234, 313, 349, 361, 377, 378, 405, 441, 444, 482, 557, 580, 581, and 586 days, respectively.
12 of 13 skin allografts obtained from the marrow donor are at present surviving in the recipients for 107, 110, 110, 110, 116, 122, 128, 143, 143, 162, 178, and 199 days, respectively; one graft was rejected at 84 days. In contrast, the radiation chimeras rejected 25 skin allografts obtained from DL-A-incompatible donors within 10.5–21 days (MST = 15.2 days). Skin transplants obtained from DL-A-identical siblings of the bone marrow donors were rejected within 20–36 days (MST = 25.8 days) in recipients of bone marrow cells obtained from littermate donors. Recipients of nonlittermate bone marrow transplants accorded such allografts a prolonged survival time of 27–76 days (MST = 56.2 days).
Prospective selection of genotypically DL-A-identical donor-recipient pairs results in the regularly reproducible long-term survival of bone marrow allografts. The radiation chimeras produced in this manner have developed a donor-specific state of unresponsiveness to kidney and skin allografts. The results are consistent with the existence in the canine species of at least three closely linked genetic systems relevant to transplantation, including DL-A, MLC, and a possible bone marrow transplantation locus.
STUDIES OF THE REGULATORY EFFECTS OF THE SEX HORMONES ON ANTIBODY FORMATION AND STEM CELL DIFFERENTIATION
Authors: Eidinger David , Garrett Thomas J. 
Published: June 2004

The primary and secondary immune responses to thymus-dependent and -independent antigens were evaluated in normal male and female mice and in castrated male mice. Both IgM antibody production in the primary response and IgG antibody production in the secondary response were enhanced in females vs. males of equivalent age. Castration of the male converted this animal to a female in terms of responsiveness to the thymus-dependent group of antigens, while inducing equivalent or even greater enhanced responsiveness over the female to the thymus-independent antigen, polyvinylpyrrolidone.
Further characteristics of the changes in lymphoid organs were determined in the castrated animal vs. normal males and females. It was shown that the spleen and thymus became markedly hyperplastic, the organ weights exceeding the female, which in turn were greater than in the male. The enhanced weight of the thymus was shown to be due to increased numbers of cortisone-sensitive cells, the absolute number of cortisone-resistant cells remaining equivalent to normal males and females. Thus, the increased thymic weight of the female also resided in the cortisone-sensitive population. Peripheral lymphocyte counts in castrated animals exceeded both normal males and females. Further experiments in gonadectomized males provided evidence that increased thymic cell activity per se played a role in enhanced response to thymus-dependent antigens, but that a thymic-derived hormone mediated the enhanced effect to the thymus-independent antigen in the castrated animal. The capacity for loss of androgenic hormone-producing tissue to generate enhanced differentiation of stem cells was denoted by experiments in which numbers of spleen colonies and uptake of 59Fe, employed as an index of hematopoiesis 1 wk after reconstitution of lethally irradiated castrated and normal recipients, were enhanced in gonadectomized male animals. Thus, in summary, changes in sex hormone levels exerted a marked influence on immune responsiveness and stem cell differentiation, by increasing numbers of functioning cells, by promoting cellular differentiation, as well as by promoting cellular function via hormonal effects.
STUDIES ON NORMAL AND IMMUNE LYMPHOCYTE TRANSFER REACTIONS IN GUINEA PIGS, WITH SPECIAL REFERENCE TO THE CELLULAR CONTRIBUTION OF THE HOST
Authors: Zakarian Siraik , Billingham R. E. 
Published: June 2004

Using guinea pigs of strains 2 and 13 and their F1 hybrids as experimental subjects, various lines of evidence have been obtained that in this species, as in all others tested, the only significant cellular antigens with which donor lymphocytes engage when normal and immune lymphocyte reactions are incited are radiosensitive leukocytes. Constitutive cells of the skin are unimportant.
(a) The intensities of these reactions in irradiated subjects are dependent upon the peripheral leukocyte concentration. When this falls below a certain threshold no reactions are incitable.
(b) Highly leukopenic animals are capable of developing immune lymphocyte transfer (ILT) reactions if normal lymphoid cells of their own genetic constitution are mixed with the putative attacking donor cells, as "supplementing antigen," before inoculation.
(c) Radiation-chimeric strain 13 animals having F1 hybrid leukocytes in their bloodstream give typical ILT reactions when challenged intradermally with strain 13 anti-2 node cells.
Exposure of strain 2 animals to 600 R does not prevent their becoming actively immunized if, 24 hr later, they are injected intradermally with strain 13 lymphocytes. However, this sensitization, revealed by the host's capacity to give delayed hypersensitivity reactions, wanes as leukopenia progresses. On the basis of this and other findings it is argued that the flare-up stage of the NLT reaction in preirradiated hosts is mainly an expression of host sensitivity against the transferred alien cells.
Two unexpected observations have been made in the course of this study: (a) F1 hybrid animals developed what appeared to be a strong delayed hypersensitivity after intradermal inoculation with parental strain lymphoid cells or antigenic extracts prepared from them. (b) If strain 13 guinea pigs which had been sensitized against strain 2 tissue antigens by intradermal injection of lymphocytes 7 days beforehand were inoculated intravenously with strain 2 antigenic extract a significant proportion of the animals developed severe delayed necrotizing reactions, recall flares, at some or all of the healed skin inoculation sites.
NATURE OF THE STIMULATING CELL IN THE SYNGENEIC AND THE ALLOGENEIC MIXED LYMPHOCYTE REACTION IN MICE
Authors: von Boehmer H. , Shortman K. , Adams Ann P. 
Published: June 2004

Thymus cells from CBA and BALB/c mice are stimulated by syngeneic peripheral lymphoid cells in a "one-way" mixed lymphocyte reaction. The stimulating cell appears to be a mature B cell.
Spleen cells from neonatal mice and thymus cells or bone marrow cells from adult mice are not able to induce DNA synthesis in syngeneic thymus cells, although they stimulate significantly allogeneic thymocytes. The ability of peripheral B cells to serve as stimulating cell in a syngeneic reaction develops with the age of the animal.
The marginal stimulation of syngeneic thymus cells when 90% pure peripheral T cells were used as stimulating cells indicated that T cells alone were ineffective in stimulating in syngeneic mixed lymphocyte reaction. However they stimulated effective allogeneic thymocytes.
On a cell-to-cell basis, light density splenic lymphocytes stimulated both syngeneic and allogeneic thymocytes better than did more dense lymphocytes.
The data obtained suggest that stimuli other than those responsible for allogeneic stimulation induce proliferation of syngeneic thymus cells under identical culture conditions.
THE ROLE OF THYMOCYTES AND BONE MARROW CELLS IN DEFINING THE RESPONSE TO THE DINITROPHENYL HAPTEN ATTACHED TO POSITIVELY AND NEGATIVELY CHARGED SYNTHETIC POLYPEPTIDE CARRIERS
Authors: Karniely Yuval , Mozes Edna , Shearer G. M. , Sela Michael 
Published: June 2004

An inverse relationship exists between the net electrical charge of immunogens and the antibodies they elicit (1). Results of an earlier study have demonstrated that the net charge phenomenon has a cellular basis, since the immune response potential of murine spleen cells to 2,4-dinitrophenyl (DNP) on a negatively charged synthetic polypeptide carrier was reduced by cell fractionation over negatively charged glass beads, whereas the response to the same hapten on a positively charged carrier was unaffected (14). To verify that the net charge correlation is expressed at the cellular level, spleen cells were fractionated over positively charged poly-L-lysine-coated glass bead columns, and their immunocompetence to DNP on positively and negatively charged carriers was tested by cell transfers in irradiated recipient mice. In this case, the fractionated cells showed reduced response potential to DNP on the positively charged carrier only. Thus, the cellular basis of the net charge phenomenon has been demonstrated for both positively and negatively charged immunogens (for the same specificity) by cell separation techniques over columns of opposite charge.
In order to establish whether the cell population relevant for the charge properties of immunogens was of thymus or marrow origin, thymocytes and bone marrow cells were selectively passed over positively or negatively charged columns and mixed with unfractionated cells of the complementary type. Transfers of the filtered and unfiltered cell mixtures in irradiated recipient mice immunized with DNP on either a positive or a negative synthetic polypeptide carrier indicated that fractionation of thymocytes, but not of marrow cells, correlated with the spleen population. Thus, thymocytes fractionated over negatively charged columns and mixed with unfractionated marrow cells exhibited reduced response to DNP on the negative carrier, but normal responses to DNP on the positive carrier. The opposite result was obtained when thymocytes were passed over positively charged columns. No effect on the anti-DNP response was detected by filtration of bone marrow cells over columns of either charge. These findings indicate that it is possible to distinguish between thymocytes on the basis of their capacity to react with more acidic or more basic surfaces and that a population of thymus-derived cells may recognize immunogens on the basis of their overall electrical charge. No evidence was found by these techniques that marrow-derived cells contribute to the net charge phenomenon.
IMMUNODEVIATION BY PASSIVE ANTIBODY, AN EXPRESSION OF SELECTIVE IMMUNODEPRESSION
Authors: Vuagnat Philippe , Neveu Thérèse , Voisin Guy André 
Published: June 2004

The effect of passively administered IgG1 and IgG2 anticarrier antibodies on the IgG1 and IgG2 antihapten response has been studied.
Guinea pigs were immunized with dinitrophenylated bovine gamma globulin mixed with purified IgG1 or IgG2 antihuman gamma globulin antibodies, i.e., antibodies directed against a limited range of the carrier determinants. Humoral IgG1 and IgG2 anti-DNP antibody contents were assayed at weekly intervals and 4 to 10 days after a booster injection of antigen in saline given on the 12th wk.
The main finding was the sustained suppressive effect of passive IgG1 anti-carrier antibodies on the active IgG1 antihapten response.
This result is compared with the enhancing effect of passive IgG1 antihapten antibodies and is discussed in the light of T cell-B cell and hapten-carrier relationships, leading to the proposal of a regulatory function of the Fc portion of the IgG1 anticarrier antibody, combined with the antigen, on the T cell.
BINDING OF ANTIGEN BY IMMUNOCYTES
Authors: Bystryn Jean-Claude , Siskind Gregory W. , Uhr Jonathan W. 
Published: June 2004

The binding of antigen to cells with antibody on their surface has been studied in a model system consisting of murine myeloma cells (MOPC 315) and DNP conjugates. Specific binding occurred between the DNP groups of DNP conjugates and cell surface immunoglobulin.
Using this model, the binding affinities of multivalent and univalent DNP conjugates were measured directly by equilibrium-binding techniques and indirectly by displacement of bound conjugate with univalent hapten. With both approaches the multivalent conjugate was shown to bind to cells with an avidity 100–300 fold greater than the univalent hapten. Nonspecific binding of unrelated protein and repeated washing of cells was found to markedly dedecrease the specific binding of univalent conjugates, presumably because the relatively weak bonds dissociate readily.
LEUKOCYTE LOCOMOTION AND CHEMOTAXIS
Authors: Zigmond Sally H. , Hirsch James G. 
Published: June 2004

Polymorphonuclear leukocyte (PMN) locomotion and chemotaxis have been evaluated by direct microscopic observation of individual cells in thin slide-cover slip preparations, and also by observations on populations of cells migrating into a Millipore filter. The direct microscopic method used the polarity of the locomoting PMNs (broad, advancing lamellipodium and knoblike constriction at the rear) to record the direction of movement. The Boyden chamber Millipore assay was made more reliable by following the front of cells advancing into the filter, rather than counting the number of cells on the lower filter surface. Special modifications of the Millipore assay were necessary in order to distinguish between influences on rate of locomotion and true chemotaxis.
In both systems the results indicate that under certain conditions leukocytes, and in particular PMNs, release into the medium a factor stimulating locomotion and exerting chemotactic action on PMNs in the vicinity. This cell-derived factor appears not to require serum factors for its release or action.