摘要:

SummaryA host‐versus‐graft reaction initiated by the intravenous injection of F1(Balb/c × C57 Black) spleen cells into Balb/c mice is characterized by hepatosplenomegaly and a marked increase in the phagocytic activity of the reticuloendothelial system. Although the host‐versus‐graft reaction is accompanied by changes in reticuloendothelial organs which are also found in the graft‐versus‐host reaction, viz., phagocytic stimulation, splenomegaly and hepatomegaly, significant differences exist in the onset, duration and nature of the functional and morphological changes produced. They occur much earlier in the host‐versus‐graft reaction and persist for shorter periods. No increase in the relative number of liver macrophages occurs in the host‐versus‐graft reaction, and splenic enlargement is due to white pulp hyperplasia with prominent germinal centre development. In a situation where the potential exists for host‐versus‐graft and graft‐versus‐host reactions to occur simultaneously, such as that created by injecting CBA spleen cells into Balb/c mice, the host‐versus‐graft reaction develops and is of sufficient intensity to prevent the transplanted cells from mounting a graft‐versus‐host reaction against the recipient animal.

ISSN:0004-945X    

DOI:10.1038/icb.1970.56

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY

摘要:

SummaryThe existence and predominantly 7S nature of macrophage‐cytophilic antibody in rabbit anti‐mouse lymphocyte serum has been confirmed. Absorption of rabbit anti‐mouse lymphocyte serum with homologous cells reduced the titre of cytophilic activity determined by both direct and indirect methods, while most of the cytotoxic and agglutinating activity was retained. This suggests the antibodies responsible for cytophilia exist as a separate class in rabbit anti‐mouse lymphocyte serum. Cytophilic antibody also promoted the attachment of thymus cells to Balb/c macrophages bothin vitroandin vivo, the attachment in the latter instance occurring only when the thymocytes were pre‐incubated with low antibody concentrations. Absorption of rabbit anti‐mouse lymphocyte serum with rabbit cells also reduced its ability in increase the localisation in the liver of injected thymocytes, while eluates of cytophilic antibody could promote significant uptake of these cells by the liver when incubated with themin vitro.The results generally confirm the opsonizing properties of rabbit anti‐mouse lymphocyte serum and indicate that rabbit cytophilic antibody is biologically active in mice.

ISSN:0004-945X    

DOI:10.1038/icb.1970.57

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY

摘要:

SummaryThe immunity of the crayfish (Parachaeraps bicarinatus) to infection by a pathogenic species of Pseudomonas following vaccination is not dependent on the production of bactericidins. Data indicate that immunity may be related to an altered activity of the phagocytic cells.

ISSN:0004-945X    

DOI:10.1038/icb.1970.58

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY

摘要:

SummaryData presented indicate that the most important change in the adaptive immune response of the crayfish (Parachaeraps bicarinatus) to infection following immunisation resides in a change in the activity of phagocytic cells. However, the activity of the cells as measured by the phagocytosis of erythrocytes can lie demonstrated only if the erythrocytes are first treated with haemolymph.

ISSN:0004-945X    

DOI:10.1038/icb.1970.59

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY

摘要:

SummaryAntigen stimulated cells leaving the lymph node by way of the efferent lymph are predominantly low density cells. 80–90% of the antibody producing cells accumulating in the density region 1·020 to 1·042 g./cc. Although 85% of the cells in this fraction were classified as antigen stimulated cells on morphological grounds, only 8% of them were synthesizing detectable antibody at the time of collection. Density gradient fractionation provides an effective means for separating these cells from the unstimulated cells in the lymph stream. Plaque‐forming cells isolated from the lymph node cover a much wider density range; some 70% of these cells have a density greater than 1·042 g./cc. Morphological analysis indicates that the low density cells produced in the lymph node by antigenic stimulation can readily leave the rode via the efferent lymph, while the high density cells, which include the plasma cells, tend to remain associated with the lymph node.

ISSN:0004-945X    

DOI:10.1038/icb.1970.60

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY

摘要:

SummaryBlood plasma of man, rabbit, mouse, rat and guinea‐pig contains 3 groups of thiol compounds. Non‐protein thiols are present to the extent of approximately 52%. The albumin fraction contains 75% thiols as determined with di‐(5‐carboxy‐4‐nitrophenyl) disulphide and about 10% higher values are obtained when determinel with 4,4′‐dipyridyldisulphide. Approximately 20% of the plasma thiols are present in proteins other than albumin.The reaction of the plasma thiols with the disulphides is mainly due to mercaptalbumin, and the reactivity of plasma thiols and the isolated albumins with di‐(5‐carboxy‐4‐nitrophenyl) disulphide and 4,4′‐dipyridyldisulphide varies according to species and pH. Human and guinea‐pig mercaptalbumin react slowly with di‐(5‐carboxy‐4‐nitrophenyl) disulphide at pH 6·5 whereas a fast reaction takes place with rat's mercaptalbumin. Intermediate reaction rates are seen with rabbit and mouse plasma.Species differences are also noted in the unmasking of thiol groups of plasma and isolated albumins by urea, guanidine hydrochloride and lauryl sulphate.Certain positions of the thiol groups in the mercaptalbumin structures are suggested and genetic considerations and evolutionary aspects of mercaptalbumin coding are discussed.

ISSN:0004-945X    

DOI:10.1038/icb.1970.61

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY

摘要:

SummaryAnaesthetized dogs, which had undergone previous splenectomy, were subjected to mild (10% blood volume), moderate (30% blood volume) and severe (46% blood volume) haemorrhage. The arterial and central venous pressures, blood volume and haematocrit were measured before and after haemorrhage. In the mild and moderately bled dogs there was a return of all observed parameters to their control, prebleed values. All of these animals survived the duration of the experiment. In the severely bled animals there was a negligible return of both arterial and central venous pressures, an absence of blood volume repletion and no significant changes in large vessel haematocrit. All of these animals died. It is suggested that these observations might result from a gross reduction in the area of the vascular bed being perfused following severe haemorrhage.

ISSN:0004-945X    

DOI:10.1038/icb.1970.62

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY

摘要:

SummaryThe action of 20 selected phages on 1187 strains ofStaphylococcus aureusfrom dairy cattle was studied. The phage patterns of 933 strains were analysed; 45 simple patterns accounted for 69·3% of strains and 6·9% were non‐typable. The phages were separated into lytic groups and the staphylococci classified into the following phage groups: group I 11·4%, group II 0·8%, group III 2·2%, group III/IV 20·9%, group IV 51·4%, miscellaneous 5·8%, others 7·5%.

ISSN:0004-945X    

DOI:10.1038/icb.1970.63

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY

摘要:

SummaryThein vivotitration curve of CO2measured in five subjects during rebreathing of 7% CO2in O2for 3 minutes was not significantly different from the correspondingin vitrotitration curve measured on arterial blood from each subject. The buffering of CO2m vivowhen measured by other methods is known to be less than it isin vitro. CO2in vivois thought to equilibrate with a well buffered compartment (intravascular) and a poorly buffered compartment (interstitial fluid). It has been suggested that HCO3—shift takes place from the intravascular compartment. During rebreathing there may be insufficient time for HCO3—shift to occur. This would explain the identical CO2titration curvesin vivoandin vitroshown by this study.

ISSN:0004-945X    

DOI:10.1038/icb.1970.64

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY

摘要:

SummaryEstimates were obtained in unanaesthetized rabbits during arterial hypoxia of the relationship between arterial PO2and (i) respiration, and (ii) autonomic effects on heart rate and total peripheral resistance. The contributions to the reflex effects made by the arterial chemoreceptors, by the arterial baroreceptors and by the lung inflation reflex were also assessed. The respiratory response was almost entirely mediated through the arterial chemoreceptors and became maximal at PaO235 mm. Hg. The autonomic effect on total peripheral resistance increased moderately at PaO250 mm. Hg, but did not change further until the PaO2fell below 35 mm. Hg following attainment of the respiratory maximum, and then increased sharply with more severe hypoxia. Above PaO235 mm. Hg the primary reflex chemoreceptor effects on total peripheral resistance were entirely suppressed by the reflex effects of hyperventilatation, and the elevation in systemic constrictor tone was mediated through the baroreceptor system. Below PaO235 mm. Hg the primary circulatory reflex chemoreceptor effects became increasingly evident, though the contribution to increased constrictor tone made by the baroreceptor system was still important during the latter part of hypoxia. Primary reflex chemoreceptor effects on heart rate were completely suppressed at PaO250 mm. Hg, and became increasingly evident at lower PaO2.

ISSN:0004-945X    

DOI:10.1038/icb.1970.65

出版商:Nature Publishing Group    

年代:1970

数据来源: WILEY