摘要:

SummaryImmunisation of mice with alcohol‐killedSalmonella typhimuriumC5 vaccine before infection withSalmonella enteritidis11RX enhanced the ability of these mice to control and eliminate a challenge dose ofSalmonella typhimuriumC5. compared to mice which only received liveSalmonella enteritidis11RX organisms. When alcohol‐killedSalmonella enteritidisSe795 vaccine was used instead of theSalmonella typhimurimC5 vaccine, this effect was not observed. These observations imply that both humoral and cellular responses are important in the expression of immunity to salmonella infections. The bearing of these results on the observations of other workers is discussed.

ISSN:0004-945X    

DOI:10.1038/icb.1976.22

出版商:Nature Publishing Group    

年代:1976

数据来源: WILEY

摘要:

SummaryThe ability of thymus‐derived (T) cell depleted mice to eliminate a dose of the normally avirulent 11RX strain ofSalmonella enteritidiswas compared to that of normal mice by following the fate of the challenge organisms in the liver and spleen of both types of mice. Although the mice did not require normal numbers of T cells to survive infection withSalmonella enteritidis11RX, T cell depiction reduced the ability of mice effectively to eliminate the organism from their tissues.In addition, T cell depletion abolished the ability of liveSalmonella enteritidis11RX vaccine to protect mice against a subsequent challenge with the virulent C5 strain ofSalmonella typhimurium.

ISSN:0004-945X    

DOI:10.1038/icb.1976.23

出版商:Nature Publishing Group    

年代:1976

数据来源: WILEY

摘要:

SummaryField studies during an epidemic of Murray Valley encephalitis (MVE) led to the isolation of MVE virus from a pool of mosquitoes(Culex annulirostris)and a sentinel chicken from Charleville, south‐west Queensland. A high proportion of domestic fowls at Charleville had antibody to MVE virus at the beginning of February 1974, in advance of the first case recognized in Queensland and allowing early warning from health authorities. A survey of antibody in domestic fowls in mid‐1974 suggested widespread activity of MVE virus in western and east‐central. Queensland. Virus isolation and serological studies showed activity in south‐west Queensland of three other viruses known to infect man, Ross River, Sindbis and Kunjin viruses.

ISSN:0004-945X    

DOI:10.1038/icb.1976.24

出版商:Nature Publishing Group    

年代:1976

数据来源: WILEY

摘要:

SummaryThe results given below show that, whilst it is not possible to transfer immunity to infections withNematospiroides dubiuspassively with serum from immune mice to normal adult mice, young born to immune females are resistant to this infection. The immunity is dependent on an intake of immunoglobulin via the milk for a period longer than 24 h. The passive transfer of immunity from immune mothers to neonatal mice does not appear to be dependent on a specific class of immunoglobulins.

ISSN:0004-945X    

DOI:10.1038/icb.1976.25

出版商:Nature Publishing Group    

年代:1976

数据来源: WILEY

摘要:

SummaryAnin vitroculture method was used to study secondary cellmediated responses to ectromelia virus infection in mice. Infected, syngeneic spleen cells or peritoneal cells were efficient “stimulator” cells when cultured with “responder” cells obtained from mice infected with ectromelia 4–6 weeks previously. The kinetics of generation of cytotoxic cells in cultures were determined; a peak occurred on days 4–5. A separation procedure performed on the cytotoxic cells showed that activity was associated mainly with the Ig‐negative subpopulation (T cell‐rich) and that H‐2 compatibility between cytotoxic cells and target cells was required. The secondary response was virus‐specific, at the level of both induction and target cell lysis, at least so far as ectromelia and lymphocytic choriomeningitis (LCM) viruses are concerned. Separation of responder cells prior to culture showed that a potent secondary response was generated with the Ig‐negative (T cell‐rich) subpopulation and only a weak response was observed when the responder cells were Ig‐positive (rich in B cells). Infected stimulator cells did not appear to secrete significant amounts of soluble antigen into the medium over 4 days of culture. Thus, antigenic patterns effective in memory T cell stimulation may be largely associated with the surfaces of infected cells. Pretreatment of ectromelia virus with UV‐ or γ‐irradiation did not impair its ability to induce antigenic changes in stimulator cells. Stimulator cells treated with UV‐ or γ‐irradiated virus for 1 h and then immediately treated with pactamycin to inhibit further viral protein synthesis and replication were efficient stimulators, thus indicating that antigenic changes are induced very rapidly on the surface of stimulator cells after uptake of virus. These treatments are being used to further characterize the cellular requirements in the stimulator population.

ISSN:0004-945X    

DOI:10.1038/icb.1976.26

出版商:Nature Publishing Group    

年代:1976

数据来源: WILEY

摘要:

SummaryThe kinetics of the popliteal lymph node response to an allograft of lymphoid cells injected into the foot pad were examined after challenge with strong (Ag‐B) and weak (non Ag‐B) transplantation antigens. The response to weak antigens was characterised by a lag period of 2 days. The response to strong antigens was more rapid in onset. Active immunisation against weak antigens accelerated the response so that it came to resemble the immediate response to strong antigens. Active immunisation against strong antigens depressed the response. This depression was reproduced by giving passive antiserum to normal recipients. Passive antiserum produced by immunisation against weak antigens was also suppressive. Adoptive transfer of immune lymphoid cells reproduced the effects seen with passive transfer of antiserum. These findings indicate that clonal expansion of antigen‐sensitive cells is characteristic of immunity to weak and not to strong antigens and that antibody is produced in both situations and has a similar suppressive effect on the cell‐mediated response in addition to its direct effect on the graft.

ISSN:0004-945X    

DOI:10.1038/icb.1976.27

出版商:Nature Publishing Group    

年代:1976

数据来源: WILEY

摘要:

SummaryLiver cirrhosis was produced in the rat by combined carbon tetra‐chloride‐phenobarbitone treatment, and the microcirculation in the cirrhotic liver was observed by a quantitativein vivotransillumination technique. The total sinusoidal flow in the observed region of the cirrhotic liver did not differ significantly from that in the normal liver, despite the reduced number of sinusoids and the increased portal venous pressure. The cirrhotic liver also presented a fast‐velocity population of portal and hepatic venules and sinusoids in addition to the normal slow‐velocity population. The possible mechanism of these “arterialized” microvessels is discussed.

ISSN:0004-945X    

DOI:10.1038/icb.1976.28

出版商:Nature Publishing Group    

年代:1976

数据来源: WILEY

摘要:

SummaryThe significance of the hepatic arterial supply in the intrahepatic microcirculation in normal and carbon tetrachloride‐induced cirrhotic livers was studied by dye injection method and by ligation of the hepatic artery. Thein vivodistribution of dye injected into the hepatic artery evidenced the presence of arterio‐venous shunts in the cirrhotic liver. When the hepatic artery of the cirrhotic liver was ligated, the elevated portal venous pressure dropped significantly, and the fast‐flowing population of microvessels and sinusoids in the bimodal frequency distribution plot disappeared. The fast‐flowing microvessel and sinusoids appeared to be the “arterial” microvessels and sinusoids, and they were converted into the slow‐flowing venous channels after hepatic arterial ligation. The transmission of arterial pressure via the A‐V shunts may be of greater significance in the pathophysiology of portal hypertension than previously believed.

ISSN:0004-945X    

DOI:10.1038/icb.1976.29

出版商:Nature Publishing Group    

年代:1976

数据来源: WILEY

摘要:

SummaryThe sera of 617 feral pigs, collected from three widely separated areas of northern and central New South Wales, were examined for antibody to Murray Valley encephalitis (MVE) virus and to Ross River virus. Haemagglutination‐inhibition (HI) antibody was detected to MVE in 58% of sera and to Ross River virus in 15% of sera.Neutralization tests suggested that the MVE HI antibody resulted from infection with MVE virus in the summers of 1971–1972 and 1972–1973 when the virus was not known to he active in New South Wales. These same tests suggested that more than one flavivirus infected the feral pigs in the summer of 1973–1974 and that Kunjin virus was active in the summer of 1975–1976.

ISSN:0004-945X    

DOI:10.1038/icb.1976.30

出版商:Nature Publishing Group    

年代:1976

数据来源: WILEY