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1.
Several prototype macrophage (MO) populations were compared for differences in ectoenzyme phenotype and polyamine content. Resident peritoneal MO and Corynebacterium parvum (CP)-activated peritoneal MO expressed unique ectoenzyme phenotypes, while bone marrow derived MO (BMDMO), obtained from stem cells after 7 days in culture with colony stimulating factor, and thioglycollate (TG)-elicited peritoneal MO exhibited a similar ectoenzyme phenotype. All of the MO populations, however, differed in polyamine accumulation patterns. These results suggest that ectoenzyme phenotypes do not serve as completely selective markers of MO differentiation. Moreover, BMDMO do not resemble steady state tissue peritoneal MO but appear to resemble inflammatory MO in several respects. Therefore activated BMDMO do not appear to provide an accurate model system for their continued use in studies to characterize the development of resident tissue MO. 相似文献
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The phylogeny of Greya Busck (Lepidoptera: Prodoxidae) was inferred from
nucleotide sequence variation across a 765-bp region in the cytochrome
oxidase I and II genes of the mitochondrial genome. Most parsimonious
relationships of 25 haplotypes from 16 Greya species and two outgroup
genera (Tetragma and Prodoxus) showed substantial congruence with the
species relationships indicated by morphological variation. Differences
between mitochondrial and morphological trees were found primarily in the
positions of two species, G. variabilis and G. pectinifera, and in the
branching order of the three major species groups in the genus. Conflicts
between the data sets were examined by comparing levels of homoplasy in
characters supporting alternative hypotheses. The phylogeny of Greya
species suggests that host-plant association at the family level and larval
feeding mode are conservative characters. Transition/transversion ratios
estimated by reconstruction of nucleotide substitutions on the phylogeny
had a range of 2.0-9.3, when different subsets of the phylogeny were used.
The decline of this ratio with the increase in maximum sequence divergence
among taxa indicates that transitions are masked by transversions along
deeper internodes or long branches of the phylogeny. Among transitions,
substitutions of A-->G and T-->C outnumbered their reciprocal
substitutions by 2-6 times, presumably because of the approximately 4:1
(77%) A+T-bias in nucleotide base composition. Of all transversions,
73%-80% were A<-->T substitutions, 85% of which occurred at third
positions of codons; these estimates did not decrease with an increase in
maximum sequence divergence of taxa included in the analysis. The high
frequency of A<-->T substitutions is either a reflection or an
explanation of the 92% A+T bias at third codon positions.
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The antiviral and antitumor activity in vitro of normal, stimulated, vaccinia virus “immune”, and activated peritoneal macrophages were compared. Activated (pyran or corynebacteria induced) PEC exhibited both antitumor and antiviral activity. Stimulated (thioglyocollate) and vaccinia virus “immune” PEC inhibited virus growth but did not possess antitumor activity. Normal (unstimulated) PEC were relatively ineffective in either activity. The antiviral activity was nonspecific, being expressed against herpes simplex and EMC viruses in addition to vaccinia. Although a possible role for interferon was suggested by the lack of activity of mouse PEC on vaccinia virus growth in heterologous FLK cells, definitive proof was not obtained. The activity was most pronounced against multiple cycles of viral infection initiated at a low multiplicity of infection. Single cycle virus growth was not affected, suggesting that the major inhibition was on subsequent cycles of virus growth. 相似文献
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