Mechanism of a reaction in vitro associated with delayed-type hypersensitivity

The cell type responsible for inhibition by antigen of migration in vitro of peritoneal exudate cells obtained from tuberculin-hypersensitive guinea pigs was studied. Exudate populations were separated into component cell types, the lymphocyte and the macrophage. Peritoneal lymphocytes from sensitive donors were the immunologically active cells in this system, the macrophages, being merely indicator cells which migrate. Sensitized peritoneal lymphocyte populations, upon interaction with specific antigen in vitro, elaborated into the medium a soluble material capable of inhibiting migration of normal exudate cells.     

Immunologic enhancement of tumor xenografts by pepsin-degraded immunoglobulin

The serums from guinea pigs previously injected with mouse Ehrlich ascites tumor cells were fractionated to obtain gamma(2)-immunoglobulin. This immunoglobulin was degraded with pepsin to obtain an F(ab')(2) fragment. Fresh tumor cells were incubated with immunoglobulin or the fragment and injected into normal guinea pigs. The growth of these cells as tumor xenografts was inhibited by the gamma(2)-immunoglobulin and enhanced by the F(ab')(2) fragment. Similar incubation of tumor cells with normal guinea pig gamma(2)-globulin or its derived F(ab')(2) fragment did not alter subsequent tumor growth.     

Leukotactic factor produced by sensitized lymphocytes

Lymph node lymphocytes obtained from guinea pigs exhibiting delayed hypersensitivity are stimulated in vitro by specific antigen to produce a soluble factor that is chemotactic in vitro for mononuclear macrophages. The material is nondialyzable, relatively heat stable, and elutes from Sephadex G-100 in the fraction containing molecules smaller than immunoglobulins.     

Plague bacillus: survival within host phagocytes

Pasteurella pestis within nelutrophiles and macrophages removed from the peritoneal cavity of guinea pigs dutring experimental plague were shown to be viable by direct microscopic observation of the infected phagocytes incubating in sutitable bacteriologic media. The time-honored hypothesis that the major determinanit of the virulence of the plague bacillius is its ability to resist ingestion by phagocytes mutst be reevaluated.     

Tumor immunity produced by the intradermal inoculation of living tumor cells and living Mycobacterium bovis (strain BCG)

The intradermal inoculation of mixtures containing living tumor cells and living Mycobacterium bovis (strain BCG) into unimmunized syngeneic guinea pigs results in an inflammatory reaction to the BCG, and there is no progressive tumor growth. In the absence of BCG the tumor grows progressively, metastasizes, and kills the animal. By conventional methods, it has not been possible to immunize syngeneic guinea pigs to the tumor used. Guinea pigs that receive mixtures of BCG and tumor cells, however, develop specific systemic tumor immunity as measured by delayed cutaneous hypersensitivity and by suppression of tumor growth.     

Agglutinating specificity for LW factor in guinea pig and rabbit anti-Rh serums

Serums produced in guinea pigs or rabbits inocutlated with monkey (rhesuts or baboon) or human red cells contain the same high-incidence agglutinating activity found in human antiLW serumls. After one absorption with LW-negative blood cells. anti-LW specificity, was observed with stronger reactions on Rh-positive than Rh-megative cells. The 85-percent specificity was obtained after complete absorption with Rh-negative blood.     

五味地龙汤的止咳作用研究

目的:探讨五味地龙汤水煎液的止咳作用.方法:用小鼠氨水引咳法、豚鼠枸橼酸引咳法及电刺激豚鼠引咳法进行实验.结果:五味地龙汤水煎液对氨水所致小鼠咳嗽及枸橼酸所致豚鼠咳嗽均有显著的止咳作用(P﹤0.01);对电刺激豚鼠所致咳嗽有显著的抑制作用(P<0.01).结论:五味地龙汤水煎液有显著的止咳作用.     

Rejection of tumor cells in vitro

The emergence of lymphoblast-like cells, capable of rapidly destroying tumor cells, was observed in primary cultures of an antigenic sarcoma transplantable in strain 13 guinea pigs. It is likely that these cytotoxic cells represent the progeny of lymphocytes sensitive to tutmor antigens that had infiltrated the tumor tissue.     

Sterility in female guinea pigs induced by injection with testis

Adult virgin female guinea pigs were injected with an emulsion of homologous adult testis and Freund's adjuvant before exposure to males. The fertility of this group was only 24 percent while the fertility of the control group was 84 percent. The testis-injected guinea pigs had also a high titer of antibodies against testis.     

Evaluation of an attenuated vaccine candidate based on the genotype C of bovine parainfluenza virus type 3 in albino guinea pigs

Bovine parainfluenza virus type 3(BPIV3) is considered as one of the most important respiratory tract pathogens of both young and adult cattle, and widespread among cattle in the world. BPIV3 was first reported in China in 2008 and four strains of BPIV3 were isolated from Shandong Province, known as genotype C(BPIV3c). Pathogen investigations had shown that BPIV3 c infection was very common among cattle in China. To date, BPIV3 can be classified into genotypes A, B and C based on genetic and phylogenetic analysis. Serological survey also demonstrates that BPIV3 infection is widespread in China, however, there is still no available vaccine for BPIV3 prevention in China nowadays. In the present study, the BPIV3 c strain SD0835 was continuously passaged on Madin-Darby bovine kidney(MDBK) cells for hundreds of times, and the pathogenicity of passage 209 was reduced in guinea pigs. The passage 209 of BPIV3 c strain SD0835 was used as a live vaccine candidate to immunize the guinea pigs. The vaccination results revealed that two vaccinations could induce excellent serum neutralizing antibody responses as well as proliferation of T lymphocytes. The vaccinated guinea pigs were well protected against challenge with a low passage of BPIV3 c strain SD0835. Additionally, the percentages of CD4~+ and CD8~+ T cell subsets of animals in vaccinated group increased after immunization; T cell subsets on day 2 after challenge in both groups decreased, and the decline of CD4~+ and CD8~+ T cell subsets levels of four guinea pigs in vaccinated group was relatively moderate, comparing with that of the control group. These data support further testing of the attenuated virus as an effective candidate vaccine.     

Immunotherapy of metastases enhances subsequent chemotherapy

In many multimodal therapies of cancer, postsurgical chemotherapy is administered before immunotherapy for treatment of micrometastatic disease. This sequence may not be the most efficacious. Experiments in which strain 2 guinea pigs bearing syngeneic L10 hepatocarcinomas were given immunotherapy showed that infiltrating immune effector cells not only were tumoricidal but disrupted the characteristically compact structure of metastatic foci. When cytotoxic drugs were administered at the peak of this inflammatory response, the survival rate of the guinea pigs increased significantly. We conclude that postsurgical immunotherapy can enhance the effect of cytotoxic drugs administered subsequently.     

Diarrhea toxin obtained from a waterbloom-producing species, Microcystis aeruginosA Kützing

A diarrhea-producing toxin from a blue-green alga, Microcystis aeruginosa Kützing, was obtained from standing laboratory cultures. The non-dialyzable fraction of the lysate from whole cells produced fluid accumulation in the ligated small intestinal loops in guinea pigs.     

Dioxin in soil: bioavailability after ingestion by rats and guinea pigs

Soil environmentally contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was given by gavage to guinea pigs and rats. The development of a characteristic clinicopathologic syndrome in guinea pigs, the induction of aryl hydrocarbon hydroxylase in rats, and the presence of TCDD in the livers of both species show that TCDD in soil exhibits high biological availability after ingestion.     

Transfer of experimental autoimmune renal cortical tubular and interstitial disease in guinea pigs by serum

Guinea pigs injected with rabbit tubular basement membranes and Freund's adjuvant develop progressive renal cortical tubulointerstitial disease and deposit autoantibodies in their cortical tubular basement membranes. The identical, even fatal, disease may be produced in normal guinea pigs by a single intraperitoneal injection of serums obtained from guinea pigs with this tubulointerstitial disease, provided such serums contain sufficient amounts of autoantibodies against tubular basement membranes.     

Tumor immunity: tumor suppression in vivo initiated by soluble products of specifically stimulated lymphocytes

Supernatant fluids of specifically stimulated lymphocyte cultures were purified. Fractions containing migration inhibition factor when injected intra-dermally into strain-2 guinea pigs produced a reaction similar in appearance to delayed cutaneous hypersensitivity. There was an accumulation of mononuclear cells at the injection sites and the growth of syngeneic tumor grafts at the sites was suppressed.     

Biosynthesis of C4 (fourth component of complement) by hybrids of C4-deficient guinea pig cells and HeLa cells

Peritoneal exudate cells from guinea pigs homozygous for a genetic deficiency of the fourth component of complement (C4) were fused in vitro with a cell line of human origin (HeLa). The resulting hybrid cells, derived from cell lines each incapable of C4 synthesis by themselves, synthesized functionally active human C4.     

A transgenic model for listeriosis: role of internalin in crossing the intestinal barrier

Listeria monocytogenes is responsible for severe food-borne infections, but the mechanisms by which bacteria cross the intestinal barrier are unknown. Listeria monocytogenes expresses a surface protein, internalin, that interacts with a host receptor, E-cadherin, to promote entry into human epithelial cells. Murine E-cadherin, in contrast to guinea pig E-cadherin, does not interact with internalin, excluding the mouse as a model for addressing internalin function in vivo. In guinea pigs and transgenic mice expressing human E-cadherin, internalin was found to mediate invasion of enterocytes and crossing of the intestinal barrier. These results illustrate how relevant animal models for human infections can be generated.     

Tumor cells secrete a vascular permeability factor that promotes accumulation of ascites fluid

Tumor ascites fluids from guinea pigs, hamsters, and mice contain activity that rapidly increases microvascular permeability. Similar activity is also secreted by these tumor cells and a variety of other tumor cell lines in vitro. The permeability-increasing activity purified from either the culture medium or ascites fluid of one tumor, the guinea pig line 10 hepatocarcinoma, is a 34,000- to 42,000-dalton protein distinct from other known permeability factors.     

GENETIC DIFFERENCES IN ANTIBODY PRODUCTION TO DETERMINANT GROUPS ON INSULIN

Highly inbred strain 2 guinea pigs can produce antibodies to portions of the insulin molecule to which strain 13 guinea pigs cannot produce antibodies. Such differences were not observable within either strain. Consequently it is probable that genetic factors regulate antibody production with respect to the determinant groups toward which antibodies are directed.     

PENICILLIN IN EXPERIMENTAL SPOTTED FEVER

Guinea pigs infected with a virulent strain of spotted fever received large doses of penicillin intramuscularly every 4 hours. The injections were begun 48 hours after the onset of fever. Controls included untreated animals and others that received one dose of spotted fever rabbit immune globulin. The penicillin had no effect on the classic symptoms of this disease and all the treated animals died. (The toxicity of penicillin for guinea pigs probably was a contributing factor.) Eight out of 16 controls died; all guinea pigs receiving globulin survived. Penicillin plasma determinations led to the belief that the treatment was adequate to bring about recovery had the agent been of any value.