We have observed that certain antisera to HLA antigens suppress the in vitro proliferation of lymphoblastoid cell lines. An antiserum to HLA-B8 demonstrated suppressor activity associated with the presence of B8 antigen on the target LCLs; this activity was removed by absorption with platelets or with B8-positive LCLs. An antiserum to HLA-DRw7 suppressed proliferation of all six DRw7-positive LCLs and none of 12 DRw7-negative LCLs; this activity was removed by absorptions with three DRw7-positive LCLs, each representing a different HLA-D allele (i.e. Dw7, 10 and 11); it could not be removed by triple serial absorptions with platelets from multiple-donor pools. These experiments indicate that the suppressor activity of this serum is specifically associated with antibodies to DRw7. Our model of LCL growth suppression by HLA antisera is easily manipulated and provides a definitive tool for further characterizing HLA antigens and antisera in a complement-independent system.
Summary The influence of polychlorinated biphenyls (PCBs) on phocine distemper virus (PDV) infections in harbour seals ( Phoca vitulina ) was studied. Six out of ten seals had been conditioned with a defined mixture of PCB‐congeneres for several weeks. Following exposure to the cell culture‐propagated PDV isolate 2558/Han88 the complete clinical picture of “1988 seal plague” was provoked in all ten seals inoculated. Four out of six PCB‐conditioned seals and two out of four seals not loaded with PCBs succumbed to the infection within three weeks post inoculation. With regard to the clinical course, duration of cell‐associated viremia, PDV‐antigen distribution in tissues of fatally infected seals and the humoral immune response to PDV no differences between PCB‐loaded and unloaded seals were recognized. Evidence was obtained that the pathogenesis of experimental PDV‐infection in harbour seals shares some features with those of canine distemper in terrestrial carnivores. In contrast, however, to experimental distemper infection of gnotobiotic dogs prompt development of high titres of PDV‐specific IgG did not correlate with recovery from infection.
When lymphoblastoid cell lines (LCL) are substituted for peripheral blood lymphocytes from human typing cell donors in HLA—D typing experiments, a data analysis program must be designed to distinguish the effect of allo‐reactivity from those peculiar to LCL, mainly the “autologous‐stimulation” effect. The computer program described in this report was created specifically for such an analysis. The rationale for the design of this program is presented in the preceding report (see this issue).
