bluuebunny/crossref_metadata_2025 huggingface dataset:
A MAJOR GENETIC LOCUS AFFECTING RESISTANCE TO INFECTION WITH MURINE LEUKEMIA VIRUSES
Authors: Pincus Theodore , Hartley Janet W. , Rowe Wallace P.
Published: June 2004

Previous studies have indicated that all naturally occurring murine leukemia viruses propagate significantly more efficiently on embryo cells of either NIH Swiss or BALB/c mice.

Studies of the plaquing efficiency of representative viruses on embryo cells of various inbred and hybrid mice indicate that the pattern of sensitivity of the cells is genetically determined. All of 23 strains tested were found to resemble either NIH Swiss (N-type) or BALB/c (B-type) with respect to plaquing efficiency of these viruses. Virus growth on embryo cells derived from (N-type x B-type)F1 hybrids indicated dominance of resistance to both types of viruses. Backcross hybrid studies indicated that a single locus is the primary determinant of the host-range patterns observed. This locus has no effect on growth of certain laboratory-passaged leukemia viruses which propagate equally well on embryo cells of all mouse strains, F1, and backcross hybrids. Though other genetic and nongenetic factors influence viral growth or expression in vitro and in vivo, the genetic locus described appears of major significance in the biology of murine leukemia.
THE FUNCTIONAL DISSECTION OF AN ANTIGEN MOLECULE: SPECIFICITY OF HUMORAL AND CELLULAR IMMUNE RESPONSES TO GLUCAGON
Authors: Senyk George , Williams E. Brady , Nitecki Danute E. , Goodman Joel W.
Published: June 2004

Bovine glucagon, a polypeptide of 29 amino acids, was immunogenic in guinea pigs. The immunologic determinants of glucagon were investigated using isolated tryptic peptides of the hormone. Antibodies from virtually all of more than two dozen animals had specificity primarily for the amino-terminal heptadecapeptide (NM) and showed little or no binding with the carboxy-terminal undeca- and dodecapeptides (C). The smallest synthetic peptide of a series initiated at residue 16 which measurably bound antibody comprised residues 5–16 of glucagon.

In cellular immune assays, both NM and C elicited delayed cutaneous reactions and inhibited the migration of peritoneal cells from immune animals. However, only intact glucagon and its C fragment stimulated lymphoid cells to synthesize DNA. While glucagon was somewhat more active than C, the addition of NM to C did not enhance its transforming activity. The smallest synthetic carboxy-terminal peptide with discernible transforming activity comprised residues 19–29 of glucagon. In both native and synthetic C peptide preparations, the undecapeptide was generally more active than the dodecapeptide, although cells from different animals gave different response patterns. The difference between the two is the presence of arginine at the amino-terminus of the peptide chain. Thus, the recognition specificity of populations of antigen-reactive cells from different animals displays a variation which is at least superficially analogous to that of populations of antibody molecules.

In limited experiments using NM and C peptides as immunogens, neither gave rise to delayed hypersensitivity or to glucagon-binding circulating antibody, following a regimen which invariably provoked these responses when glucagon itself served as the immunogen.

These results indicate that glucagon was cleaved by trypsin along functional lines into two parts, one of which housed the major antigenic determinant and the other of which carried the major immunogenic determinant, and they are highly compatible with a two-cell mechanism of immune induction. An apparent dissociation between the capacity to provoke delayed hypersensitivity reactions and to transform antigen-reactive cells in culture was observed.
THE DISTRIBUTION OF ANTIGENIC DETERMINANTS IN RAT SKIN COLLAGEN
Authors: Lindsley Herbert , Mannik Mart , Bornstein Paul
Published: June 2004

Immunological studies of rat skin collagen were carried out with a sensitive and quantitative radioimmunoassay. Hyperimmune rabbit antisera to rat skin collagen and isolated α2 chains were used. Iodine-labeled α chains and CNBr-produced peptides served as test antigens, and native collagen, α chains, and CNBr peptides were employed as inhibitors in the assay.

The α1 and α2 chains were immunologically distinct. Although the α1 chain was not immunogenic, antibodies to α1 were detected in antisera to the intact collagen molecule. The major antigenic determinant of the α1 chain was located in α1-CB6 which constitutes the carboxy-terminal region of the chain. The α2 chain contained two non-cross-reacting antigenic determinants, one in the amino-terminal region (α2-CB1) and the other in the carboxy-terminal region (α2-CB5) of the chain. The native collagen molecule was less effective than isolated α chains in inhibiting binding of labeled peptides to antisera, indicating that antigenic determinants were less accessible in the triple helical molecule.

These immunologic studies are consistent with preliminary comparative biochemical data which indicate that interspecies structural differences in collagen predominate at both the amino- and carboxy-terminal ends of the chains.
CELLULAR IMMUNITY IN VITRO
Authors: Simon Harvey B. , Sheagren John N.
Published: June 2004

An in vitro model of cellular immunity in the guinea pig was established. Animals were immunized with tubercle bacilli, bovine gamma globulin, or picrylated human serum albumin in complete Freund's adjuvant. Oil-induced peritoneal exudates from immune and control animals were cultured overnight with and without specific antigen. The cultures were washed and the macrophage monolayers were infected with Listeria monocytogenes. At intervals the monolayers were lysed and the numbers of viable intracellular bacteria were quantitated by pour plate cultures. Random monolayers were also evaluated in sequence by visually counting the intracellular bacteria on Gram-stained plates. Both methods demonstrated that the macrophages from immune animals had markedly enhanced listericidal activity when the peritoneal exudates were cultured with antigen before infection. Macrophage migration inhibition was also demonstrated under these conditions.

The experiments reported here describe an in vitro model of cellular immunity which will allow separation and recombination of cell types and direct assay of cell products in efforts to elucidate further the mechanisms of the immunologically mediated enhancement of macrophage bactericidal capacity.
IN VIVO STUDIES IN C4-DEFICIENT GUINEA PIGS
Authors: Ellman Leonard , Green Ira , Judge Francis , Frank Michael M.
Published: June 2004

Guinea pigs with a genetically determined total deficiency of the fourth component of complement have been studied for various in vivo immunological functions. Passive cutaneous anaphylaxsis, contact and delayed hypersensitivity, and the cellular exudative response to a foreign body were normal. These animals also have normal direct and reverse passive Arthus reactions which suggest that they possess a mechanism to bypass C4 and directly activate late-acting complement components. This would appear to be an unequivocal demonstration of an alternate pathway in the complement sequence. Immune clearance of guinea pig erythrocytes sensitized with rabbit antibody was impaired in the deficient animals. Antibody production in C4-deficient animals was impaired for two of the three antigens studied.
ANTIBODIES TO POLYNUCLEOTIDES IN HUMAN SERA: ANTIGENIC SPECIFICITY AND RELATION TO DISEASE
Authors: Koffler D. , Carr R. , Agnello V. , Thoburn R. , Kunkel H. G.
Published: June 2004

The specificities of anti-polynucleotide antibodies found in human sera were studied using several immunological procedures. Anti-native DNA (NDNA) antibodies and certain anti-double-stranded RNA (DSRNA) antibodies were found to react with single-stranded DNA (SDNA), and anti-NDNA antibodies were observed to react more avidly with SDNA than with NDNA in most sera tested. Antibodies to NDNA showed no preferential reactivity with NDNA or SDNA derived from mammalian tissue, bacterial, or viral sources. Precipitating antibodies reactive with individual bases, with common determinants of bases, and with common determinants of SDNA and NDNA were detected utilizing synthetic polydeoxyribonucleotides. Antibodies to DSRNA were also heterogeneous and reactive with both Poly A · Poly U and Poly I · Poly C in addition to reactivity with Poly A and SDNA. In contrast, antibodies to a ribonucleo-protein determined by hemagglutination and by precipitation showed no reaction with NDNA, SDNA, or DSRNA.

Serial studies of serum specimens from patients with systemic lupus erythematosus (SLE) indicated that anti-NDNA antibodies were closely associated with disease activity. Titers of antibodies to SDNA or DSRNA were also frequently increased during these periods but in addition showed peaks during quiescent periods. Anti-NDNA antibodies were detected in most patients' sera at sometime during the course of the disease. Three patients were observed with active SLE, who did not develop anti-NDNA antibodies, even in the presence of severe renal disease. Evidence that other antigen-antibody systems may also play a role in the pathogenesis of the renal disease was particularly apparent in these patients. Anti-ribonucleoprotein antibodies were not well correlated with the peaks of antibody activity of other polynucleotide antibodies, suggesting that an independent immunogen was responsible for induction of these antibodies.

The close association of certain populations of anti-polynucleotide antibodies during the course of active SLE, the presence of cross-reacting antigenic determinants of SDNA, NDNA, and DSRNA, the preferential avidity of anti-NDNA antibodies for SDNA, and the frequent increase of anti-SDNA antibodies in SLE and other diseases associated with active tissue destruction suggest that SDNA is a ubiquitous antigen that may stimulate the formation of antibodies reactive with a variety of polynucleotides.
PECULIAR IMMUNOBIOLOGY OF BONE MARROW ALLOGRAFTS
Authors: Cudkowicz Gustavo , Bennett Michael
Published: June 2004

Mice are capable of rejecting H-2-incompatible bone marrow grafts after a single lethal exposure to X-rays. The onset of rejection begins 18–24 hr after transplantation and is completed by 96 hr. Maturation of this type of allograft reactivity does not occur until the 22nd day of life. In adult mice, the resistance to marrow allografts can be weakened by administration of cyclophosphamide or dead cultures of Corynebacterium parvum, but not heterologous anti-thymocyte serum. Sublethal exposures to X-rays 7 or 14 days before transplantation also weaken resistance. There is considerable interstrain variation in the ability of mice to resist allografts, even when H-2 differences between hosts and donor are kept identical. Although H-2 incompatibility is a necessary prerequisite for resistance, additional genetic factors influence the outcome of marrow allografts, presumably by controlling recognition. The regulator genes are determinant specific and the alleles for resistance or responder status appear to be dominant. The responder phenotype is expressed by hemopoietic cells and not by the environment. Accordingly, resistance is conferred to otherwise susceptible mice upon transfer of bone marrow cells but not of serum. The production and differentiation of effector cells for marrow graft rejection are thymus independent.

In conclusion, bone marrow allografts elicit a particular transplantation reaction, previously unknown, in irradiated mice. Peculiar features of this reaction are the lack of proliferation of host lymphoid cells, tissue specificity, thymus independence, and regulation by genetic factors which apparently do not affect the fate of other grafts.
TOXIC EFFECTS OF STREPTOCOCCAL M PROTEIN ON PLATELETS AND POLYMORPHONUCLEAR LEUKOCYTES IN HUMAN BLOOD
Authors: Beachey Edwin H. , Stollerman Gene H.
Published: June 2004

Purified M protein isolated from Group A streptococci produced cytotoxic reactions in normal human blood in vitro. In the presence of M antigen, platelets aggregated, fused, and lysed. Polymorphonuclear leukocytes (PMN) surrounded the platelet aggregates, then became highly vacuolated and lysed. In addition, PMN progressively lost their capacity to phagocytose unrelated bacteria and to migrate in glass capillary pipettes.

Platelet-PMN reactions were directly proportional to the type-specific precipitin reactivity of each M preparation and could be removed with homologous M antibody, only. Moreover, the reactivity of M protein was abolished by enzymatic digestion with trypsin, but not with lysozyme, strongly suggesting that cell-wall mucopeptide was not involved.

Preliminary studies showed that platelet-PMN reactions require heat-stable and heat-labile serum factors, presumably antibody and complement. It is suggested that cytotoxic determinants are uncovered by the extraction and purification process and are intimately associated with the type-specific M determinant, possibly in a molecular complex.
BEHAVIOR OF ATTENUATED MYCOBACTERIA IN ORGANS OF NEONATAL AND ADULT MICE
Authors: Costello Richard , Izumi Takateru , Sakurami Takehiko
Published: June 2004

The consequences of Calmette-Guérin bacillus (BCG) vaccination were followed in newborn and adult mice.

BCG failed to multiply in the organs of adult mice when administered peritoneally. In contrast, extensive multiplication of the vaccine occurred in both splenic and pulmonary tissue after its peritoneal administration to newborn mice. This absence of tuberculostasis occurred during the period when the animal's spleen, lung, and thymus were rapidly growing.

Animals achieved similar levels of resistance to virulent respiratory challenge 10 wk after vaccination irrespective of whether the vaccine had been administered when the mice were newly born and BCG had multiplied in vivo or administered when the animals were fully grown and the BCG had remained in the dormant state.

Although neonatal infection with BCG was severe, as shown by the large numbers of organisms recovered from the animals' tissues, the animals suffered no mortality or overt signs of disease. Neonatal vaccination did not significantly affect either the animal's growth rate or the gross development of its organs.
CELLULAR AND HUMORAL RESPONSE TO TRANSPLANTATION ANTIGENS
Authors: Cerottini J.-C. , Nordin A. A. , Brunner K. T.
Published: June 2004

After transfer into heavily-irradiated allogeneic mice, spleen cells were found to produce two types of effector cells directed against the recipient alloantigens, namely alloantibody plaque-forming cells (PFC) and cytotoxic lymphocytes (CL). Both types of effector cells were detectable in vitro by virtue of their lytic effect on target cells carrying the recipient alloantigens.

Alloantibody PFC activity was dependent on the presence of an exogenous source of complement and could be inhibited by the addition of heterologous antisera to mouse µ-chain or Fab fragment in the assay system. CL activity was independent of added complement, was not affected by anti-immunoglobulin antisera, but was inhibited by the addition of antibody against target cell alloantigens. Treatment of the transferred spleen cells with anti-θ-serum and complement before in vitro assays for PFC and CL completely abolished the CL activity but had no effect on alloantibody-plaque formation. These results indicate that the two types of effector cells can be differentiated in vitro by virtue of their susceptibility to anti-θ-serum and the mechanisms by which they cause cell lysis.
EXPERIMENTAL INFECTION OF THE SKIN IN THE HAMSTER SIMULATING HUMAN IMPETIGO
Authors: Dajani Adnan S. , Wannamaker Lewis W.
Published: June 2004

The interaction between staphylococci and Group A beta hemolytic streptococci in mixed lesions was investigated in an experimental impetigo model. A strain of staphylococcus of phage Type 71, which has been shown in vitro to produce a bacteriocin for streptococci and other Gram-positive organisms, eliminates or reduces Group A streptococci in mixed lesions. In contrast, staphylococcal strains of phage Types 75 and 81, which do not produce a demonstrable bacteriocin in vitro, exhibit no such effect.

Some variation was noted in the in vivo response of two different streptococcal M Types to the bactericidal effect of phage Type 71 staphylococci. Bacterial antagonism is more pronounced when staphylococci and streptococci are injected simultaneously into animals than when staphylococci are superimposed on preexisting streptococcal lesions.

Marked variations were found in the numbers of viable streptococci (colony-forming units) recovered from individual lesions containing identical mixtures of streptococci and phage Type 71 staphylococci. The frequency of a demonstrable bactericidal effect was related to the number of streptococci injected. With small inocula of streptococci, the tendency towards an all-or-none effect was particularly striking. No evidence of selection of streptococcal or staphylococcal mutants which might explain this phenomenon was obtained.

These observations suggest that the bactericidal effect of phage Type 71 staphylococci on other Gram-positive organisms, previously demonstrated in vitro, appears to operate also in vivo.
CUTANEOUS BASOPHIL (JONES-MOTE) HYPERSENSITIVITY AFTER "TOLEROGENIC" DOSES OF INTRAVENOUS OVALBUMIN IN THE GUINEA PIG
Authors: Richerson Hal B.
Published: June 2004

Cutaneous basophil hypersensitivity (CBH) was studied for tolerogenic requirements. Graded doses of intravenous ovalbumin (OA) were given to guinea pigs which were subsequently immunized appropriately to produce CBH, classic delayed hypersensitivity (classic DH), and/or antibodies of both passive cutaneous anaphylaxis (PCA) and hemolytic types.

Results showed that doses of intravenous antigen sufficient to induce subsequent tolerance for classic DH and hemolytic antibody actually stimulate CBH reactivity and PCA antibody production.

Other studies of dose-route relationships for CBH production demonstrated that optimal immunogenic dosage requirements for CBH varied widely with route of antigen employed. OA in incomplete Freund's adjuvant (IFA) injected into footpads had low dosage requirements, intravenous OA had high dose requirements, and intradermal soluble OA dosage requirements were intermediate.

The observation that blatant immunogenic responses occur during the early period of tolerance induction amplifies the significant heterogeneity of the cellular immune response and may be of importance in understanding tolerogenesis.

Similar immunogenic-tolerogenic requirements and the prime role played by the basophil suggest a developmental or functional relationship between CBH and PCA antibody response.
LYMPHOID CELL DEPENDENCE OF EOSINOPHIL RESPONSE TO ANTIGEN
Authors: McGarry M. P. , Speirs R. S. , Jenkins V. K. , Trentin J. J.
Published: June 2004

Quantitative determinations were made of the capacity of isogenic bone marrow, spleen, and thymic cells from primed and/or nonprimed mice to repopulate the hemopoietic tissues and to mount an inflammatory and antibody response to specific antigen (tetanus toxoid) in heavily irradiated and reconstituted recipients.

Spleen cells from primed mice but not from normal mice had the capacity to adoptively transfer an anamnestic antitoxin titer in irradiated animals in the absence of transplanted bone marrow cells, and during retarded myeloid regeneration.

Spleen cells alone or bone marrow cells alone produced an insignificant and a moderate peritoneal eosinophil response, respectively, to antigen.

In the presence of bone marrow cells, normal spleen cells augment the capacity of recipient animals to mount an eosinophil response to antigen. A much greater augmentation occurs in animals reconstituted with splenic or thymic cells from primed animals.

The increase in antitoxin titers appears to be independent of the response of eosinophils since: (a) marked accumulation of eosinophils can occur in animals with no measurable humoral antitoxin, and (b) high antitoxin titers can occur in animals which do not have marked eosinophil responses.

It is suggested that a thymic-derived or thymic-dependent mononuclear cell population is necessary for optimal eosinophil response to antigen. The neutrophil and mononuclear cell responses to antigen are determined by different mechanisms from those which determine the eosinophil response. These studies together with earlier findings strongly indicate that the eosinophil granulocytes play a role in the immune response to antigen.
IMMUNOCOMPETENT CELLS OF THE CHICKEN
Authors: McArthur W. P. , Chapman J. , Thorbecke G. J.
Published: June 2004

Specific antisera to chicken thymus and to bursa of Fabricius were obtained in rabbits. After appropriate absorption and dilution all four anti-thymus sera, in the presence of guinea pig C', killed >90% of thymus and ≦12% of bursa cells. They were cytotoxic for approximately 50% of spleen cells and did not affect antibody-forming cells. The surface antigen detected by these antisera was named chicken T-lymphocyte antigen (CTLA).

Two of four anti-bursa sera, under similar conditions, killed >90% of bursa cells and ≦10% of thymus cells. These antisera were cytotoxc for a large percentage of antibody-forming cells and killed approximately 30% of spleen cells The other two anti-bursa sera were somewhat less potent but showed similar specificity. The surface antigen detected by these antisera was named chicken bursa-derived lymphocyte antigen (CBuLA).

Rabbit antisera to chicken immunoglobulin were cytotoxic for bursa but not for thymus cells and killed a similar percentage of spleen cells as did anti-bursa sera. They were also cytotoxic for antibody-forming cells.
PASSIVE ANTIBODY AND THE IMMUNE RESPONSE
Authors: McBride Raymond A. , Schierman Louis W.
Published: June 2004

The isoimmune response of fowl inoculated with RBC coated with antibody was investigated. Anti-B antiserum from a single animal was used to coat different donor type RBC. With each donor type RBC the immune response to the coated determinants is suppressed. Enhancement of the immune response to noncoated determinants occurs when they are products of an allelic gene or belong to a different blood group system. Coating some B antigen determinants suppresses the response to noncoated determinants of the same antigen, i.e., determinants which are products of the same B gene. Varying the quantity of passive antibody revealed that the degree of suppression and the degree of enhancement are negatively correlated.

These findings support the concept that antibody-coated determinants function as carrier for noncoated determinants, provided a certain physical association exists between them. A further interpretation of these studies is that in certain situations an antibody to one antigen may interfere with events which lead to an immune response to a different antigen. The possibility, that the protection afforded by ABO incompatibility against Rh isoimmunization is because of a similar phenomenon, is discussed. A hypothesis is presented which states that where the immune response to certain antigens behaves as a dominantly inherited trait, and is associated with histocompatibility type, the nonresponder animals possess an antibody (perhaps cell bound) which interferes with the response to determinants for which it does not have specificity. Responders are assumed to lack this antibody because it has specificity for their major histocompatibility antigens.
TONE AND REACTIVITY OF VASCULAR SMOOTH MUSCLE IN GERMFREE RAT MESENTERY
Authors: Baez Silvio , Gordon Helmut A.
Published: June 2004

Microcirculatory observations and measurements were made by in vivo microscopy in 35 germfree and 26 conventional rats. The rate of vasomotor activity, "vasomotion," of precapillary arterioles was found markedly decreased in the germfree animals.

All precapillary vessels in the germfree rats were markedly hyporeactive to the catecholamines, epinephrine and norepinephrine, as compared to similar vessels of conventional rats. The vessels in the germfree animals were also less responsive to vasopressin but not angiotensin.

A greater lumen:wall ratio of primary arterioles, but not of secondary arterioles and metarterioles, found in germfree animals is related to change in vessel lumen alone without concomitant change in wall thickness.

The germfree rat is characterized by possessing a hypotonic, catecholamine-refractory mesoappendix microvasculature.
MACROPHAGE-MELANOMA CELL HETEROKARYONS
Authors: Gordon Saimon , Cohn Zanvil
Published: June 2004

Mouse peritoneal macrophages possess a specific plasma membrane receptor for antibody-coated particles. Sheep red cells coated with rabbit 7S antibody attach readily to the macrophage surface and are subsequently interiorized. The fusion of macrophage with nonphagocytic mouse melanoma cells produces heterokaryons in which the macrophage receptor is drastically altered. The receptor is present shortly after fusion and heterokaryons are actively phagocytic. The ability to bind and ingest red cells is, however, progressively lost over the next 12–24 hr and does not reappear thereafter.

Exposure of heterokaryons to trypsin (1–100 µg/ml for 30 min at 37°C) results in the reappearance of initial receptor activity and the unmasking of the surface receptor. This property is again lost upon subsequent cultivation. The masking process takes place when cells are cultivated in the absence of IgG so that the adsorption of antibody from the medium is not responsible for this phenomenon. Inhibition of heterokaryon protein synthesis preserves phagocytic activity in a reversible fashion and prevents the masking of macrophage receptors. Inhibition of melanoma RNA synthesis before fusion is also able to block subsequent masking, but is ineffective if delayed until after fusion. Ultraviolet irradiation of the melanoma cell before fusion prevents subsequent masking, whereas similar treatment of the macrophage has no effect.

Cells differ markedly in their ability to mask the macrophage phagocytic receptor after fusion. Ehrlich ascites tumor cells mask the receptor rapidly, primary chick fibroblasts minimally, and embryonic chick erythrocytes not at all.
BIOLOGICAL ACTIVITY OF COMPLEMENT IN VIVO
Authors: Snyderman Ralph , Phillips Jean K. , Mergenhagen Stephan E.
Published: June 2004

The importance of C5 in the generation of complement (C)-dependent chemotactic activity in vitro is well recognized. However, the actual role C5 may play in the accumulation of polymorphonuclear leukocytes (PMN) at inflammatory sites in vivo has not been established. Injection of glycogen or endotoxin into the peritoneal cavities of guinea pigs resulted, shortly thereafter, in the local accumulation of PMN. Preceding the influx of leukocytes, the peritoneal fluid became chemotactic for rabbit PMN in vitro. The majority of this activity could be attributed to a cleavage product of C5 (C5a). Similarly, injection of endotoxin into the peritoneal cavity of C5-normal mice resulted in the generation of a chemotactic factor for mouse PMN which was followed by the accumulation of PMN in the peritoneal fluid. In contrast, injection of endotoxin into the peritoneal cavity of C5-deficient mice resulted in the generation of virtually no detectable chemotactic activity and a markedly depressed accumulation of PMN during the first 24 hr after injection. The data suggest that C5 plays an important role in the early phases of PMN accumulation in response to inflammatory stimuli. The rapid accumulation of PMN in response to an inflammatory stimulus such as bacterial endotoxin would be expected to be a major factor in host defense against proliferation and dissemination of infectious agents.
STUDIES ON ANTIBODY-PRODUCING CELLS
Authors: Gudat Fred G. , Harris T. N. , Harris Susanna , Hummeler Klaus
Published: June 2004

Mice injected with sheep RBC and then, 4 days later with thymidine-3H, were sacrificed on the day of thymidine-3H injection or 1 or 2 days later. Hemolytic antibody plaque preparations were made of cells from the draining lymph nodes by a thin-plating procedure permitting collection of isolated PFC for electron microscopic examination and radioautography.

Of cells obtained on the day of thymidine-3H injections, 65% of the labeled PFC were in the lymphocytic category, in comparison with 13% found previously in the entire population of such cells. The remaining 35% were plasmablasts in early stages of differentiation. Cells obtained 1 day after the thymidine-3H injections showed a shift to a majority of labeled cells in the plasmacytic category. Also, the plasmablasts were substantially more differentiated than those of the previous day, and some mature plasma cells were now seen. The labeled PFC obtained on day 2 gave no indication of further differentiation.

Cells of rabbit lymph nodes labeled in vitro with thymidine-3H showed a range of labeled PFC. The majority were in the plasmacytic category, including some mature plasma cells.

The data from the experiments with in vivo labeling suggest a direct differentiation from antibody-synthesizing lymphocytes to plasma cells. Further, the in vivo experiments indicated that differentiation from nascent lymphocyte to plasma cell could be essentially completed within 1 day.
CELL-TO-CELL INTERACTION IN THE IMMUNE RESPONSE
Authors: Miller J. F. A. P. , Sprent J. , Basten A. , Warner N. L. , Breitner J. C. S. , Rowland G. , Hamilton J. , Silver H. , Martin W. J.
Published: June 2004

Experiments were designed to test the possibility that thymus-derived (T) cells cooperate with nonthymus derived (B) cells in antibody responses by acting as passive carriers of antigen. Thoracic duct lymphocytes (TDL) from fowl γG-tolerant mice were incubated in vitro with fowl anti-mouse lymphocyte globulin (FALG), which was shown not to be immunosuppressive in mice. On transfer into adult thymectomized, irradiated, and marrow protected (TxBM) hosts together with a control antigen, horse RBC, a response to horse RBC but not to fowl γG was obtained. By contrast, TxBM recipients of nontolerant, FALG-coated TDL responded to both antigens and the antibody-forming cells were shown to be derived from the host, not from the injected TDL. These findings suggested that, under the conditions of the experiment, triggering of unprimed B cells in the spleens of TxBM hosts was not achieved with antigen-coated tolerant lymphocytes.

Another model utilized the ability of B cells to bind antibody-antigen complexes. Spleen cells from TxBM mice, incubated in vitro with anti-fowl γG-fowl γG·NIP, were injected with or without normal TDL (a source of T cells) into irradiated hosts. Only mice given both cell types could produce an anti-NIP antibody response. In a further experiment, spleen cells from HGG·NIP-primed mice were injected together with NIP-coated B cells (prepared as above) into irradiated hosts. A substantial anti-NIP antibody response occurred. If, however, the T cells in the spleens of HGG·NIP-primed mice were eliminated by treatment with anti-θ serum and complement, the NIP response was abolished. It was concluded that antigen-coated B cells could not substitute for T cells either in the primary or secondary response.

Treatment of T cells from unprimed or primed mice with mitomycin C impaired their capacity to collaborate with B cells on transfer into irradiated hosts. Taken together these findings suggest that before collaboration can take place T cells must be activated by antigen to differentiate and in so doing may produce some factor essential for triggering of B cells.
NEW APPROACHES FOR THE LABORATORY RECOGNITION OF M TYPES OF GROUP A STREPTOCOCCI
Authors: Rotta Jiri , Krause Richard M. , Lancefield Rebecca C. , Everly William , Lackland Henry
Published: June 2004

The successful classification of Group A streptococci by the capillary precipitin technique requires a complete series of M type antisera which are sufficiently potent and specific to give unequivocal type-specific reactions with all the serotypes. Specific antisera for this purpose have been prepared by absorption with heterologous streptococci.

Unabsorbed antisera have been employed here in the Ouchterlony double-diffusion agar-gel test to identify the M type of streptococci. Techniques have been developed for making this method of M typing fully reliable. The results reported here confirm and amplify the original findings of Michael and Massell (3). With crude HCl extracts and unabsorbed M type antisera, a precipitin line due to the M protein and another to the group-specific carbohydrate are the two major reactions observed. These reactions, however, are usually readily distinguishable. There was a surprising lack of cross-reactive precipitin lines due to non-type-specific protein antigens in the extracts.

Although many of the unabsorbed M type antisera can be employed in the double-diffusion tests, the group-specific antibody must be removed from some of the unabsorbed antisera to avoid confusing cross-reactions. Absorption of these antibodies has been achieved by means of a specific immunoabsorbent column prepared from para-aminophenyl-ß-N-acetylglucosamine and cyanogen bromide-activated Sepharose. Excellent agreement was observed between the M typing results obtained on 117 field strains by the conventional capillary precipitin method and the Ouchterlony double-diffusion method.
H-2-LINKED GENETIC CONTROL OF IMMUNE RESPONSIVENESS TO OVALBUMIN AND OVOMUCOID
Authors: Vaz Nelson M. , Phillips-Quagliata Julia M. , Levine Bernard B. , Vaz Eda M.
Published: June 2004

Immune responsiveness of inbred mice to low doses of ovalbumin or ovomucoid is under control of single dominant genes closely linked to alleles of the H-2 locus. High responsiveness to ovomucoid is linked with the H-2a and H-2k alleles, and to ovalbumin with the H-2b, H-2d, and H-2q alleles.
THE INFLUENCE OF POSTNATAL DEVELOPMENT ON DRUG-INDUCED HEPATIC PORPHYRIA AND THE SYNTHESIS OF CYTOCHROME P-450
Authors: Song Chull S. , Moses Harold L. , Rosenthal Alan S. , Gelb Nancy A. , Kappas Attallah
Published: June 2004

The mitochondrial enzyme δ-aminolevulinate synthetase (ALAS) controls the rate-limiting step in the synthesis of porphyrins and heme. An experimental form of hepatic porphyria can be readily elicited in laboratory animals, such as the rat, by drugs and foreign chemicals which are known to enhance the de novo formation of this enzyme in the liver.

The present study shows that there is a striking refractoriness to the induction of ALAS during the perinatal period in the rat. Chemicals which have potent porphyria-inducing activity in adult animals have no significant inducing effect on hepatic ALAS in neonates. The ultrastructural changes which accompany the induction of ALAS by drugs and chemicals in adult liver also fail to take place in the livers of neonates. A progressive capacity for responding to the action of chemical inducers of hepatic ALAS does, however, develop in neonatal animals so that by approximately 5–6 wk of age experimental porphyria can be elicited as effectively in them as in adults.

The reasons for the refractoriness of hepatic ALAS to induction in the perinatal period are not known; but the findings of this study make it clear that ALAS belongs to that increasingly large group of liver enzymes in mammals whose appearance, increase of activity, or inducibility is developmentally determined.

The occurrence of developmental changes in the indicibility of ALAS in the liver of neonates also provided an opportunity to study the relationship of this enzyme activity to the drug-mediated induction of the hepatic hemoprotein cytochrome P-450. This inducible hemoprotein serves as the terminal oxygenase in the microsomal mixed-function oxidase system in the liver. The results of this study indicate that, in contrast to the refractoriness of ALAS to induction, significant drug-induced changes of hepatic P-450 content and of hemeprecursor incorporation into this cytochrome do take place in neonates. The synthesis of P-450 thus appears to be under a regulatory control different from that of ALAS in neonates, and the relation between ALAS activity and P-450 formation is not therefore a direct one.
CELLS MEDIATING SPECIFIC IN VITRO CYTOTOXICITY
Authors: Golstein Pierre , Svedmyr Erik A. J. , Wigzell Hans
Published: June 2004

Spleen cells from mice immunized with allogeneic tumor cells are incubated on different fibroblast monolayers. The nonadsorbed cells are tested for cytotoxicity against 51Cr-labeled target cells. The cytotoxicity of nonadsorbed cells is much lower after incubation on fibroblasts syngeneic to the immunizing tumor cells than after incubation on fibroblasts syngeneic to the immune cells. This specific decrease of cytotoxic activity depends on the duration and temperature of incubation on monolayers. After incubation the monolayers are trypsinized and pure populations of adsorbed lymphocytes isolated by density gradient fractionation. The cytotoxicity of such trypsin-eluted, gradient-purified lymphocytes is much higher when these lymphocytes are isolated from fibroblasts syngeneic to the immunizing tumor cells than when they are isolated from fibroblasts syngeneic to the immune cells. These experiments demonstrate specific adsorption of immune cells onto fibroblasts carrying the immunizing antigens, and thus prove the existence of specific receptors at the surface of these immune cells.

Spleen cells from mice immunized with two types of allogeneic tumor cells bearing different H-2 antigen alleles are incubated on different fibroblast monolayers. The results of such experiments show a differential specific adsorption pattern, suggesting independent adsorption of two populations of immune cells bearing receptors directed against either one or the other immunizing H-2 antigen. The existence of at least a majority of cells, each of which is homogeneous as to the specificity of its receptors, makes it likely that specific receptors are synthetized by the cells that bear them. The role of specific receptor-bearing cells in the killing process is discussed.
SIGNIFICANCE OF BIVALENCE OF ANTIBODY IN VIRAL NEUTRALIZATION
Authors: Rosenstein Robert W. , Nisonoff Alfred , Uhr Jonathan W.
Published: June 2004

The role of bivalence of antibody in its capacity to neutralize virus was studied with rabbit antibodies to the bacteriophage, ϕX174. Univalent Fab or Fab' fragments of IgG isolated from antiviral antisera obtained early in the immunization schedule had virtually no activity compared to that of the intact IgG. When the antibodies were isolated from antisera of the same rabbits several months later, the univalent fragments and IgG were essentially equal in activity. The results are interpreted on the basis that an IgG molecule, because of its bivalence, has a higher effective combining affinity (avidity) than a univalent fragment. After prolonged immunization, however, the affinity of univalent antibody becomes sufficiently high that it exceeds a threshold value, above which further increase in affinity, through bivalence, is no longer significant. The results could explain the variability in relative effectiveness of univalent antibodies observed in previous studies. These data, and the fact that F(ab')2 fragments from either "early" or "late" antisera were as effective as IgG, indicate that fragment Fc is not a significant factor in neutralization.

No differences in dissociation from the virus of univalent antibody from early and late antisera could be demonstrated by dilution at temperatures up to 47°C. The attachment at sites of neutralization on the virus appears to be functionally almost irreversible in this system.
SPECIFIC IMMUNE RESPONSE GENES OF THE GUINEA PIG
Authors: Bluestein Harry G. , Green Ira , Benacerraf Baruj
Published: June 2004

The lymph node cells from all L-glutamic acid and L-tyrosine (GT) responder random-bred guinea pigs were susceptible to lysis by strain 2 anti-strain 13 isoantisera in the presence of complement. These same antisera were cytolytic for lymph node cells of only some of the GT nonresponder animals. However, after absorption with cells, from a nonresponder guinea pig, susceptible to lysis, the anti-strain 13 antisera were no longer able to lyse cells from any GT nonresponder guinea pigs while retaining a large measure of their cytolytic activity for cells of all GT responder guinea pigs. Thus, at least two major strain 13 histocompatibility specificities are expressed on the cells of random-bred guinea pigs. The genetic locus controlling the expression of only one of those strain 13 histocompatibility specificities is linked to the GT immune response gene.
CHOLESTEROL METABOLISM IN THE MACROPHAGE
Authors: Werb Zena , Cohn Zanvil A.
Published: June 2004

Macrophage membrane cholesterol is present in two subcellular cholesterol pools, a rapidly exchanging compartment comprising about two-thirds of the total cholesterol, and a slowly exchanging compartment comprising one-third of the total. The morphological identification of the kinetically distinguishable pools proceeded by alteration of each compartment. Trypsin treatment markedly decreased the rate of cholesterol exchange without removing cholesterol from the membrane. Recovery of normal exchange rates took more than 7 hr and required protein synthesis. This suggested that a plasma membrane receptor is involved in positioning of lipoproteins for exchange, and is consistent with the plasma membrane localization of the rapidly exchanging compartment.

Extensive pinocytosis by nondegradable dextran, dextran sulfate, or sucrose resulted in the accumulation of many secondary lysosomes, thus increasing the relative proportion of intracellular membranes. The measurable granule membrane area, cholesterol content, phospholipid content, and the relative size of the slowly exchanging cholesterol compartment all increased. The amount of intracellular membrane altered by extensive phagocytosis of latex particles also increased the size of the slowly exchanging cholesterol compartment. This suggested that the slowly exchanging pool of cholesterol represented the intracellular membranes primarily of lysosomal origin.

Rabbit alveolar macrophages and thioglycollate-stimulated peritoneal macrophages contain many secondary lysosomes as a result of multiple bouts of in vivo phagocytosis and pinocytosis. In both of these cells the fast and slow pools are equal in size. The increased cholesterol content was attributable to the increase in the relative size of the slowly exchanging compartment. L-cells and melanoma cells also exchange their cholesterol with that of serum lipoproteins. Both cells contain few cholesterol-rich intracellular membranes, and had lower cellular cholesterol contents. In these cells the slowly exchanging pool was a minor contribution to cell cholesterol. Studies with these cells provided further evidence for the lysosomal membrane and plasma membrane localization of the slowly and rapidly exchanging cholesterol compartments.
BLOOD COAGULATION INITIATION BY A COMPLEMENT-MEDIATED PATHWAY
Authors: Zimmerman Theodore S. , Müller-Eberhard Hans J.
Published: June 2004

A variety of complement-activating substances, including inulin, immunoglobulin aggregates, bacterial endotoxins, and staphylococcal protein A, were found to initiate blood coagulation through a complement-mediated pathway. These substances markedly accelerated blood coagulation in normal rabbit blood. That this clot-promoting activity requires an intact complement system was demonstrated by an almost total lack of effect on blood from rabbits with an inherited deficiency of the sixth component of complement (C6). Small amounts of isolated C6 conferred to C6-deficient blood the ability to respond with accelerated coagulation upon activation of the complement system. In addition, it was determined that activation of complement through the previously described C3 activator system resulted in the initiation of blood coagulation. The participation of C1, C2, and C4 was not necessary.
SYNTHESIS OF PLASMA MEMBRANE-ASSOCIATED AND SECRETORY IMMUNOGLOBULIN IN DIPLOID LYMPHOCYTES
Authors: Lerner Richard A. , McConahey Patricia J. , Jansen Inga , Dixon Frank J.
Published: June 2004

The half disappearance time for detectable plasma membrane-associated and cytoplasmic immunoglobulin after treatment of continuously growing diploid lymphocytes with inhibitors of protein and RNA synthesis was studied. Also, the amount of plasma membrane-associated and cytoplasmic immunoglobulin of synchronized cells in the G1 phase of the cell cycle has been studied. Plasma membrane-associated immunoglobulin has a half disappearance time of 45 min after inhibition of protein synthesis. By contrast, after treatment of cells with actinomycin D for 24 hr, plasma membrane-associated immunoglobulin remains relatively unchanged whereas cytoplasmic immunoglobulin decreased by almost 90%. In the G1 phase of the cell cycle, plasma membrane-associated immunoglobulin and cytoplasmic immunoglobulin were 70 and 10%, respectively, of that in logarithmically growing cells, and the half disappearance of M-Ig after treatment of cells with puromycin was again 45 min. In toto, these results suggest that perhaps secreted and plasma membrane-associated immunoglobulin may be separately controlled by the cells.
REGULATION OF THE IMMUNE SYSTEM BY SYNTHETIC POLYNUCLEOTIDES
Authors: Stout Robert D. , Johnson Arthur G.
Published: June 2004

Addition of polyadenylic-polyuridylic acid in complex form (poly A:U) without antigen to a suspension of spleen cells obtained from BALB/Aj mice primed 6 wk previously with human γ-globulin (HGG) resulted in an immediate fourfold increase over background number of anti-HGG rosette-forming cells (RFC). Culture of similar cells in the presence of puromycin for 1–6 hr before poly A:U did not significantly reduce the response. Continued culture of primed spleen cells in the presence of poly A:U, resulted in a decrease of RFC to background levels within an hour followed by an increase again 6 hr later. This later increase in RFC was inhibited by addition of puromycin to the culture medium.

The nonspecific stimulation by poly A:U of antibody production by primed spleen cells also was induced in vivo. Increases in splenic RFC were detectable 6 hr after intravenous injection of poly A:U alone, without antigen, into primed mice. The response peaked at 18 hr and had dissipated completely within 3 days. A second injection of poly A:U 24 hr or later after the first injection resulted in a second response, similar to the first with respect to kinetics and intensity. Rosette formation by poly A:U-stimulated cells could not be inhibited by mitotic poisons, but was inhibited by treatment of the cells with goat anti-mouse γ-globulin serum, suggesting that the antibody involved was a 7S γ-globulin.

The decrease in RFC induced by culture of primed cells for 1 hr in poly A:U paralleled a decrease in secondary responsiveness of the cells to antigen. This poly A:U-induced inhibition of secondary responsiveness could be reversed by suspending the treated cells in supernatant fluids derived from poly A:U-stimulated cultures. The reversal was specific in that supernatant fluids removed from bovine serum albumin (BSA)-primed cells by poly A:U did not stimulate the response of HGG-primed cells to HGG. However supernatant fluids from BSA-primed cells caused the production of anti-HGG RFC if BSA rather than HGG was used as triggering antigen. The active factor in the supernatant fluids appeared to be a 7S γ-globulin since activity was lost after 45 min incubation of the supernatant fluids in the presence of goat anti-mouse 7S γ-globulin serum.