bluuebunny/crossref_metadata_2025_split huggingface dataset:
MACROPHAGE-MELANOCYTE HETEROKARYONS
Authors: Gordon Saimon , Cohn Zanvil 
Published: June 2004

High yields of mouse macrophage-melanocyte heterokaryons and macrophage-macrophage homokaryons were obtained through the virus-induced fusion of cells spread on a glass surface. After fusion there was a striking reorganization of cellular architecture by means of a colcemid-sensitive process. Heterokaryons were isolated through the use of differential trypsinization and many underwent division to form melanocyte-like hybrids. The selective uptake of dextran sulfate by macrophages served as a useful cytoplasmic marker in identifying hybrids.
Many characteristic macrophage properties were altered in the heterokaryons. Within an hour of fusion macrophage nuclei became swollen, nucleoli were more prominent, and increased nuclear RNA synthesis occurred. 3 hr after fusion, a wave of DNA synthesis took place in the previously dormant macrophage nuclei.
The fate of typical macrophage markers was examined in both heterokaryons and homokaryons. Macrophage homokaryons continued to exhibit active phagocytosis of sensitized erythrocytes, whereas this capacity was lost irreversibly in heterokaryons. The loss of phagocytic activity of heterokaryons occurred at an exponential rate and was accelerated by high concentrations of calf serum.
Another macrophage surface marker, a divalent cation-dependent adenosine triphosphatase (ATPase), could be demonstrated histochemically on heterokaryons. Shortly after fusion, it was present in discrete regions, but it became more diffuse and disappeared within a day.
Acid phosphatase-positive secondary lysosomes and retractile lipid droplets disappeared from heterokaryons but continued to accumulate in macrophage homokaryons.
These observations indicate that typical macrophage properties cease to be expressed in heterokaryons, and melanocyte functions presumably predominate in heterokaryons and hybrids.
MECHANISM OF EOSINOPHILIA
Authors: Basten Antony , Boyer Markley H. , Beeson Paul B. 
Published: June 2004

The phenomenon of eosinophilia was studied in rats using inoculation with Trichinella larvae as the experimental stimulus. Comparisons were made between the eosinophil response accompanying active infestation via the gastrointestinal tract and that resulting from parenteral inoculation of larvae or their products.
A vigorous eosinophilia could be provoked by a single intravenous injection of intact parasites. In this circumstance the larvae lodged in the lungs causing an acute inflammatory reaction which led to their disintegration within 24 hr. Intraaortic injection also produced a significant response, whereas inoculation of the same number of parasites by the intramuscular, intraperitoneal, or subcutaneous routes did not cause eosinophilia. Eosinophilia likewise failed to develop if parasites were homogenized before intravenous injection, so that they were not arrested in the lungs.
Antibody levels, as measured by a hemagglutination technique, using whole larval extract as antigen, did not correlate closely with the eosinophil response.
The findings are interpreted as suggesting that increased eosinophil production is induced under some circumstances as a consequence of interaction between intact parasites and certain host cells in blood and tissue. No evidence was found for the existence of a specific constituent of the parasite capable of stimulating eosinophil production.
Attention is directed to features of eosinophilia which fit with the concept that this phenomenon belongs in the category of immunologic reactions.
STUDIES ON THE PATHOGENESIS OF FEVER
Authors: Cheuk S. Fai , Hahn Helmut H. , Moore Douglas M. , Krause Donald N. , Tomasulo Peter A. , Wood W. Barry 
Published: June 2004

Suppression of the pyrogen-producing capacity of exudate granulocytes results from incubation of the cells in plasma, serum, or Ringer's solution. When transferred in this state and incubated in isotonic NaCl, the cells release much less pyrogen than untreated exudate cells. The suppressive effect is reversible and appears to involve the cellular uptake of calcium ions.
In contrast, regeneration of pyrogen-producing capacity in depleted exudate cells occurs only when the cells are incubated in serum. The process resembles activation and requires the cellular synthesis of protein.
A PLAQUE ASSAY FOR ENUMERATING ANTIGEN-SENSITIVE CELLS IN DELAYED-TYPE HYPERSENSITIVITY
Authors: Bloom Barry R. , Jimenez Luis , Marcus Philip I. 
Published: June 2004

A general method is described for enumerating antigen-sensitive lymphocytes obtained from individuals having delayed hypersensitivity, in this case from highly tuberculin-sensitive guinea pigs. The method is based on the observation that resting lymphocytes are generally unable to support replication of RNA viruses, whereas antigen-"activated" lymphocytes can.
Lymph node lymphocytes from individual animals were cultured in the presence or absence of tuberculin purified protein derivatives (PPD). After various periods of time, the cells were infected either with Newcastle disease virus or vesicular stomatitis virus, and plated in agar over a monolayer of cells susceptible to the virus. Wherever a lymphocyte yielded infectious virus, a discrete plaque in the monolayer could be seen. The increase in plaques of the antigen-stimulated cells over the background of the control sample was taken as the number of antigen-sensitive cells in the population. When lymphocytes from normal guinea pigs or from guinea pigs immunized to produce only circulating antibody to PPD were similarly tested, no increase in plaque-forming units (PFU) was observed.
The average increase in PFU due to antigenic stimulation varied from 1 per 1000 lymphocytes at 24 hr to 16 per 1000 lymphocytes at 96 hr. By employing inhibitors of mitosis (colchicine, vinblastine, and thymidine) it was evident that the increase in PFU at least up to 48 hr was primarily due to initial antigen-reactive cells and not their progeny.
SYNERGISTIC INTERACTION OF MACROPHAGES AND LYMPHOCYTES IN ANTIGEN-INDUCED TRANSFORMATION OF LYMPHOCYTES
Authors: Seeger Robert C. , Oppenheim Joost J. 
Published: June 2004

The role of macrophages and lymphocytes in antigen-induced transformation of lymphocytes has been investigated. Lymphocytes and macrophages were obtained from inbred strain 13 guinea pigs which were either unimmunized or immunized with complete Freund's adjuvant (CFA) or tetanus toxoid in CFA. The transformation response to PPD or tetanus toxoid was assayed by tritiated thymidine incorporation.
Addition of macrophages to immune lymphocytes significantly increased their response to purified protein derivative (PPD) or tetanus toxoid. This was observed if the macrophages were (a) "immune" or "nonimmune", (b) unirradiated or irradiated (3000 R), (c) 99% pure, and (d) peritoneal or alveolar in origin. Neither immune nor nonimmune macrophages were able to induce nonimmune lymphocytes to respond to PPD or tetanus toxoid. When macrophages were incubated with PPD or tetanus toxoid and then washed, they stimulated immune lymphocytes to transform. An incubation time of ½ hr was adequate, however, 2–4: hr was optimal.
These studies indicate (a) that antigen-induced transformation of lymphocytes is greatly enhanced by macrophages; (b) that macrophage-antigen interaction can antecede lymphocyte-antigen interaction and results in macrophages which are able to stimulate lymphocyte transformation; and (c) that the immunological memory requisite to elicit specific transformation responses is a property of the lymphocyte and not the macrophage.
SOME PHYSICAL AND RADIOBIOLOGICAL PROPERTIES OF IMMUNOLOGICALLY REACTIVE MOUSE SPLEEN CELLS
Authors: Osoba David 
Published: June 2004

Three classes of immunologically reactive cells, differing only slightly in size from each other, are required for the production of hemolysin-forming cells in culture. The three classes of cells can be detected in the normal mouse spleen by the combined use of rosette formation, velocity sedimentation, and irradiation.
One class of cells (peak sedimentation velocity, 3.2 mm per hr) forms rosettes. The capacity of these cells to participate in immune responses to foreign erythrocytes is inhibited by relatively low doses of irradiation. These cells may be the immediate precursors of hemolysin-forming cells.
A second class of cells (peak sedimentation velocity, 3.6 mm per hr) facilitates the production of hemolysin-forming cells by small numbers of normal spleen cells. Their facilitative activity is resistant to a relatively large dose of radiation. They do not form rosettes.
The requirement of a third class of cells was deduced from the results of mixing experiments. Neither rosette-forming cells nor spleen cells largely depleted of rosette-forming cells could give rise to hemolysin-forming cells when cultured either alone or in the presence of large numbers of heavily irradiated cells. However, when rosette-forming cells, cells depleted of rosette-forming cells, and heavily irradiated cells were mixed together, hemolysin-forming cells were produced. The peak responses were found in fractions sedimenting at 4 mm per hr. Thus, it is suggested that these fractions contain a third class of cells. This class of cells does not form rosettes, but its function is inhibited by relatively low doses of radiation.
PHYLOGENY OF IMMUNOGLOBULIN STRUCTURE AND FUNCTION
Authors: Clem L. W. , Small P. A. 
Published: June 2004

The giant grouper, Epinephelus itaira, was shown to synthesize 16 and 6.4S antibodies specific for the dinitrophenyl determinant (DNP). Sera obtained at various intervals between 1 month and 2 yr after initial immunization contained both species of antibody; no temporal synthesis was evident.
Equilibrium dialysis studies employing ϵ-dinitrophenyl-amino caproic acid were conducted with purified grouper antibodies specific for DNP. The 16S antibody preparations obtained at 1 and 2 months of immunization showed heterogeneity of hapten binding indicative of two populations of combining sites. One-half of these sites (an average of four sites per 16S molecule) exhibited an average intrinsic association constant (Ko) of ∼106M–1; the Ko of the remaining four-sites was ∼104M–1. Thus, the valence of the grouper 16S antibody molecule appears to be eight although the distribution of the high and low Ko sites is unknown, i.e., are they each on the same or on different molecules? The 16S antibody preparations obtained after more prolonged immunization exhibited increasingly lower Ko values; the so-called low Ko sites were no longer detectable. These findings are in contrast to reports of rabbit IgG antibodies showing an increase in Ko with increased time.
The 6.4S antibody preparations obtained from the 1 and 2 month antisera had Ko values of ∼106M–1 and a valence of one. These antibodies would not precipitate with antigen. The 6.4S antibody preparations obtained at later times showed decreasing Ko values comparable to those of the 16S antibodies from the same bleedings.
Studies on the thermodynamic parameters of the hapten-antibody interaction showed the grouper 16 and 6.4S antibodies to be similar to each other. These data also showed that the enthalpy and entropy changes of grouper antibody-hapten reactions resemble those reported for rabbit IgG antibodies to this hapten. It is thus suggested that, although considerable evolution of immunoglobulin classes has occurred between fish and rabbits, the antibody combining site may have remained relatively unchanged during a large part of evolutionary time.
STUDIES ON THYMUS FUNCTION
Authors: Stutman Osias , Yunis Edmond J. , Good Robert A. 
Published: June 2004

Significant immunological restoration of 45-day old, neonatally thymectomized C3Hf mice was obtained by the cooperation of syngeneic newborn or embryonic hemopoietic liver cells with thymic function. Thymic function or cells alone are almost ineffective or restore approximately 10% of the animals. Newborn liver cells are effective in association with thymus grafts or humoral thymic function (thymoma grafts and thymus or thymomas in diffusion chambers). Embryonic liver cells are ineffective, even in large numbers, when associated with humoral thymic function. On the other hand, embryonic liver cells are effective in the cooperative effect only in association with viable thymus grafts, preferably syngeneic, whether the grafts were placed subcutaneously, intraperitoneally, or under the kidney capsule. Dispersed viable thymic cells are ineffective in association with embryonic liver cells. Cells capable of cooperating with humoral thymic function start to appear to embryonic liver by day 19–21 of gestation and are detectable until day 5–6 postbirth. Embryonic hemopoietic liver cells from 12 to 18 days of gestation contain cells capable of cooperation only with viable free thymus grafts and not with humoral thymic function.
A prethymic cell population of partially differentiated cells of hemopoietic origin, insensitive to humoral activity of the thymus but requiring thymic stroma and traffic through the thymus is postulated to explain our results. This population of prethymic cells can become postthymic through this process and eventually develop into competent cells. Postthymic cells are characterized by their sensitivity to humoral activity of the thymus and by their wide distribution in the lymphohemopoietic tissues of newborn and young adult mice.
MORPHOLOGY AND PEROXIDASE CYTOCHEMISTRY OF MOUSE PROMONOCYTES, MONOCYTES, AND MACROPHAGES
Authors: van Furth Ralph , Hirsch James G. , Fedorko Martha E. 
Published: June 2004

Mouse promonocytes have been identified and studied in cultures of bone marrow cells. These cells have a diameter of 14–20 µ, and in stained preparations reveal a large, indented or folded nucleus, and basophilic, finely granular cytoplasm. The living promonocyte viewed by phase contrast shows additional features: nucleoli, small dense bodies, and vesicles in the cytoplasm adjacent to the nuclear hilus, and slight membrane ruffling. Prominent ultrastructural components of promonocytes include a well developed Golgi apparatus, small numbers of centrosomal granules and vacuoles, extensive ribosomal aggregates, and finger-like projections of the cell surface.
Promonocytes engage in pinocytosis and phagocytosis, but they are less active in these functions than are peripheral blood monocytes of peritoneal macrophages.
Promonocytes are positive for peroxidase, the reaction product being localized to granules most of which are centrally situated in the cell. Monocytes in blood or in inflammatory peritoneal exudates display much smaller numbers of peroxidase-positive granules, and various types of mature mouse macrophages are peroxidase negative.
IMMUNOGLOBULIN SPOTS ON THE SURFACE OF RABBIT LYMPHOCYTES
Authors: Pernis Benvenuto , Forni Luciana , Amante Luisa 
Published: June 2004

Small and medium lymphocytes from the peripheral blood and lymphoid tissues of the rabbit react in suspension with antibodies directed against different immunoglobulin determinants. Through immunofluorescence, it was possible to show that numerous discrete spots on the surface of the positive lymphocytes carry immunoglobulin molecules.
The positive lymphocytes are about one-half of all lymphocytes in the different preparations; thymus lymphocytes are all negative.
With antisera specific for rabbit IgM as well as with antisera directed against allotypic determinants specific for IgM or IgG, it was possible to show that about nine-tenths of the immunoglobulin-positive lymphocytes carry IgM molecules on their surface.
With antisera directed against a- and b-locus determinants, it was also possible to demonstrate that both heavy and light chains were present in the surface immunoglobulins. Furthermore, in animals which were heterozygous at the a or the b locus, it was found that each lymphocyte had immunoglobulins synthesized under the influence of only one of two alleles.
A very small proportion of lymphocytes could be shown to have a specific surface reaction with one antigen (horse ferritin); the proportion of these cells increased very much after immunization.
INDUCTION AND REVERSAL OF IMMUNE PARALYSIS IN VITRO
Authors: Byers V. S. , Sercarz E. E. 
Published: June 2004

Induction of the immune response can only be completed after antigen is removed from the cellular environment. Primed rabbit lymph node fragments were cultured in vitro with 5 mg/ml BSA. If antigen was removed from the fragments 2 hr later, they produced a normal anti-BSA response, which was first evident 5 days later. If antigen removal was delayed for 3 days, the onset of the response was postponed for 2 to 3 days.
Pulses with BUDR marked the periods of cell proliferation in both sets of cultures, and established that the postponement of antibody production was preceded by a postponement in the wave of proliferation among precursors of antibody forming cells.
The similarity in avidity of antibody-containing fluids from normal and postponed cultures support the idea that the same cell population produced the response in each case.
It was concluded that a reversible state of paralysis could be instituted in antigen-responsive cells, and this state did not depend upon cell-killing. The widespread incidence of temporary paralysis as an early aspect of the immune response was discussed.
COMPLEMENT AND COMPLEMENT-LIKE ACTIVITY IN LOWER VERTEBRATES AND INVERTEBRATES
Authors: Day N. K. B. , Gewurz H. , Johannsen R. , Finstad J. , Good R. A. 
Published: June 2004

A purified cobra venom factor with C-inhibiting activity also promotes lysis of erythrocytes in fresh mammalian serum. Lysis-inducing activity of purified cobra venom factor was found in sera of lower vertebrates including the cyclostome hagfish and in invertebrates. Lysis-inducing activity was most effective with frog serum. Frog serum was found to be more hemolytic for Es in the presence of CVF than when cells were sensitized with hemolysin. The hemolysis induced by CVF with frog serum, as in the higher vertebrates, was inhibited when sera were pretreated with known C inhibitors including heat, chelators, endotoxin, immune complexes, and CVF itself.
Complexes formed with CVF and either frog serum or invertebrate hemolymph promoted lysis of indicator cells in the presence of frog serum in EDTA. This lysis was most marked when the starfish-CVF complex was used and was C-dependent. Conversely, complex formed with frog serum and CVF promoted lysis of E in the presence of invertebrate hemolymph (Limulus) in EDTA. Hence, serum components were to some degree at least interchangeable between vertebrate sera and invertebrate hemolymph. Lysis-inducing activity of purified CVF occurs in a wide range of species, has revealed activities resembling those of terminal C-components in lower vertebrates and invertebrates, and provides one means for study of C and C-like activities in primitive species.
GLUCOCORTICOIDS AND CELLULAR IMMUNITY IN VITRO
Authors: Cohen Irun R. , Stavy Lary , Feldman Michael 
Published: June 2004

We studied the influence of glucocorticoids on the sensitization phase as well as on the cytolytic effector phase of an in vitro lymphocyte-mediated immune reaction. Lymphocytes obtained from the spleens or lymph nodes of unimmunized inbred rats were sensitized against foreign rat or mouse embryonic fibroblasts in cell culture. The capacity of the sensitized lymphocytes to produce a cytolytic effect was tested by transferring them to target fibroblast cultures. Injury to target fibroblasts was measured by release of radioactive 51Cr from previously labeled fibroblasts or by direct count of viable fibroblasts after incubation with sensitized lymphocytes. Various concentrations of water-soluble hydrocortisone or prednisolone were added to cell cultures during the 5 day sensitization phase and/or during the subsequent cytolytic effector phase and the influence of these hormones on the number and cytolytic capacity of the lymphocytes was measured.
During the sensitization phase, the presence of glucocorticoid hormones, at concentrations of about 1 µg/ml, led to a profound decrease in the total number of recoverable lymphocytes. However, the per cent of large transformed lymphocytes was much greater in these treated cultures. The antigen-specific cytolytic capacity per cell of the glucocorticoid-treated lymphocytes, after the hormone was removed, was several times greater than that of lymphocytes sensitized in the absence of added hormones.
Glucocorticoids influenced the effector phase of the reaction by inhibiting lymphocyte-mediated injury to target fibroblasts. The hormones, at concentrations of about 1 µg/ml, inhibited the cytolytic effect by about 50% without reducing the viability of the sensitized lymphocytes. Dose-dependent toxicity to lymphocytes and increasing inhibition of cytolytic effect appeared at higher concentrations of hormones.
Thus, hydrocortisone and prednisolone, at concentrations of about 1 µg/ml, did not suppress the induction of sensitization, a process which they seem to facilitate in vitro. However, similar concentrations of these hormones appear to inhibit the cytolytic effector mechanism of sensitized lymphocytes. These findings may be relevant to the use of glucocorticoids as immunosuppressive agents in vivo.
HETEROGENEITY OF THE CELLULAR IMMUNE RESPONSE
Authors: Bast Robert C. , Simpson Blanche A. , Dvorak Harold F. 
Published: June 2004

Antigen-mediated stimulation of thymidine incorporation was demonstrated in lymph node cells from guinea pigs immunized with 100 µg human serum albumin in either Freund's incomplete or Freund's complete adjuvant. Animals receiving HSA in IFA exhibited both cutaneous basophil (Jones-Mote) hypersensitivity and lymphocyte stimulation at 1, but not at 6 wk after immunization. Significant stimulation required ≥ 10 µg HSA/ml of culture. Sensitization with HSA in CFA produced delayed hypersensitivity and permitted lymphocyte stimulation at both 1 and 6 wk. Stimulation was observed with as little as 0.1 µg HSA/ml at the later interval.
Administration of 5 mg HSA intravenously at the time of sensitization with 100 µg HSA in IFA reduced but did not eliminate both CBH and lymphocyte stimulation at 1 wk.
Antigen-specific inhibition of macrophage migration could be demonstrated with exudates from animals immunized with HSA in CFA, but not with HSA in IFA at 3 wk after sensitization.
HSA was cleared from depots of CFA and IFA at similar rates, but significantly more antigen appeared in the plasma and subsequently in the draining lymph nodes following administration in IFA. Conversely, accumulated antigen disappeared more rapidly following CFA immunization.