Natural killer cell activity in lung cancer patients

A total of 50 lung cancer (CA) patients and 20 normal persons as controls were included in our study. We obtained lymphocytes from heparinized blood by Ficoll-Hypaque gradient method, and after the macrophages were removed, they were incubated with 51Cr-labelled K562 cells at concentrations of 100:1, 50:1, 12.5:1 for four hours. We calculated the cytotoxicity activity and lytic unit (LU) of natural killer (NK) cells. Significant impairment was noted in the comparison of NK cytotoxicity and LU between stage III-M1 lung CA patients (n = 28) and the control group. However, significant impairment was also noted in stage III-M1 and III-M0 patients. Four cases in stage I underwent surgery, and the NK cytotoxicity before the operation was noted to be low. After the operation, the NK cytotoxicity increased. These results indicate that NK cytotoxicity assay was impaired in stage III-M1 lung CA and also suggest that it may act as a therapeutic guide in determining the results of the operation.

[Study of the natural killer cell activity in lung cancer patients]

A total of 50 lung CA patients and 20 normal persons as control were included in our study. We obtained lymphocytes from heparinized blood by Ficoll-Hypaque gradient method and after incubation with Cr51 labelled K562 cells at concentrations of 100: 1, 50:1, 12.5:1 for four hours, we calculated the cytotoxicity activity of NK cells. Significant impairment was noted in the comparison of NK cytotoxicity between stage III-M1 lung CA patients (n = 28) and the control group (n = 20) (E/T; 50:1, 29.55 +/- 24.20% vs 49.83 +/- 14.46%, p less than 0.001; E/T: 25:1, 10.23 +/- 7.19% vs 27.66 +/- 6.06%, p less than 0.001). 4 cases in stage I underwent surgery, the NK cytotoxicity before the operation was noted to be low, E/T: 25:1, 9%, 11%, 14% and 19% respectively. After the operation, the NK cytotoxicity was increased to 33%, 35%, 42% and 44% respectively. 3 stage I lung CA patients has continuously followed up, 2 relapsed cases had decreased NK cytotoxicity to 22% and 25%. These results indicated that the NK cytotoxicity assay was impaired in stage III-M1 lung CA and also suggested that it may act as a therapeutic guide for the results of the operation.

Studies of natural killer cell activity. I. Normal range of a natural killer cell activity in the healthy Chinese

This study was undertaken to establish a normal distribution curve for natural killer (NK) cell activity in healthy Chinese. NK cell activity was detected in 123 persons of different age groups, from the newborn to 84 years of age. None had any reported infection. The mononuclear cells were obtained from peripheral blood and cord blood for NK test; K562 cells were used as target cells to assay NK cell activity. The results indicated that cord blood had the lower NK cell activity. Increasing NK cell activity was seen with increasing age. In the 20 year to 49 year range, the NK cell activity reached maximal value. The NK cell activity gradually decreased when the age was greater than 50 years.

Immunological studies with the HA1 and HA2 polypeptides of influenza A virus haemagglutinin

HA1 and HA2 polypeptides of influenza A virus haemagglutinin (HA) were separated in purified form using electrophoresis in SDS containing polyacrylamide gels (PAGE) or chloroform-methanol extraction. The populations of HA1 polypeptides were immunogenic but considerably less so than the intact HA molecule and induced antibody which cross-reacted with influenza A and B viruses. After absorption with heterologous influenza B virus, the cross-reacting antibodies were removed and the HA1 antisera then possessed antibodies which reacted only with the cross-reactive (CR) determinants of the HA of the homologous influenza A virus and viruses of the same subtype. Neither strain-specific (SS) nor virus-neutralizing antibodies were detected in these anti-HA1 sera. HA2 polypeptides were less immunogenic and anti-HA2 antisera after absorption with influenza B virus failed to react with influenza A virus in immuno double diffusion tests and only reacted with partially denatured HA in the more sensitive single radial diffusion tests.