Rh-immunization by pregnancy: results of a survey and their relevance to prophylactic therapy.

A series of Rh-negative primiparae has been studied in order to gain further insight into the process of immunization by pregnancy. The distribution of foetal cell counts in blood samples taken after delivery was determined for 2,029 mothers giving birth to ABO-compatible babies and for 417 mothers with ABO-incompatible babies.A total of 760 mothers were tested for the development of Rh antibodies six months after the delivery of an ABO-compatible Rh-positive baby and 236 were further followed up through a second Rh-positive pregnancy. The incidence of anti-D six months after delivery is estimated to be 8.5%, and there is evidence of a direct relation between the count of foetal cells after delivery and the risk of developing antibodies. A further 8.5% of mothers were estimated to develop anti-D by the end of the second pregnancy, and it is postulated that these individuals had been primed by the first pregnancy. There is some evidence that the larger stimuli of Rh-positive blood in the first pregnancy are more likely to result in overt antibody formation, while the smaller stimuli are more likely to prime, antibodies not being detected until a second stimulus occurs during the second pregnancy.These findings are relevant to the programme for preventing Rh-immunization by injecting anti-D gammaglobulin.

Cysteine proteases of Trichomonas vaginalis degrade secretory leukocyte protease inhibitor.

Sexually transmitted diseases, including trichomoniasis, are risk factors for acquisition of human immunodeficiency virus (HIV) infection. Enhancement mechanisms are unknown. Secretory leukocyte protease inhibitor (SLPI) from saliva appears to prevent transmission of HIV through inhibition of virus entry into monocytic cells in vitro. This study was undertaken to determine if secreted cysteine proteases of Trichomonas vaginalis degrade SLPI and render it nonfunctional. It was determined if SLPI levels were decreased in vaginal fluids from pregnant women infected with T. vaginalis. Isolated proteases were incubated with recombinant human SLPI, and the degradation was followed by Western analysis with SLPI antiserum. SLPI levels were measured by ELISA in vaginal fluids from women infected with T. vaginalis and uninfected controls. Cysteine proteases cleaved SLPI and rendered it nonfunctional. Median levels of SLPI from infected patients were 26% of those of controls (P <.005). The degradation of SLPI in association with trichomonal infection may increase the risk of HIV acquisition.

Total T lymphocytes in primary bronchial carcinoma.

Percentage and absolute levels of circulating T lymphocytes were measured in 48 patients with bronchial carcinoma. These were compared with control values from nine healthy adults and 19 age-matched patients with benign disorders. A further 20 patients who had been given postoperative immunotherapy after complete resection of bronchial carcinoma were also studied. There was no significant difference in the mean percentage T cells between the groups. Lymphopenia, however, was a feature of the bronchial cancer patients with metastatic disease. This resulted in a significant diminution of absolute T cells in this group. There is no evidence, with the technique employed in this study, of a total T-cell deficiency in early bronchial carcinoma.

Lea blood group substance degradation in the human alimentary tract and urinary Lea in coeliac disease.

The Lewis (Lea) blood group substance in alimentary tract liquids is a large molecule. Ileal and jejunal mucosal preparations can act upon it to produce dialysable serologically active Lea. Alimentary tract bacteria cannot produce a similar effect. Plasma, serum and urinary Lea are principally in the form of a dialysable moiety. It is suggested that this dialysable form is produced by mucosal degradation of large-molecule Lea in the alimentary tract. The small-molecule Lea is absorbed, transported in the plasma and then excreted. Both secretor and non-secretor patients with duodenal ulcer and inflammatory bowel disease have normal urinary Lea titres. Non-secretor coeliac patients who have not regenerated normal jejunal mucosa on treatment have significantly reduced urinary Lea titres when compared with healthy individuals. One non-secretor coeliac patient who had regenerated a normal jejunal mucosa on treatment had a normal urinary Lea titre. Coeliac patients have normal titres of salivary Lea.

Prevention of Rh-haemolytic disease: results of the Liverpool "low-risk" clinical trial.

A clinical trial is reported in which Rh-negative primiparae, just delivered of an Rh-positive ABO-compatible infant and in whom fetal cell counts after delivery suggested less than 0.2 ml of circulating fetal blood, were treated with about 200 mug of anti-D gammaglobulin. Three (0.36%) out of 844 women thus treated developed anti-D in the subsequent six months; this is 10% of the incidence in untreated controls. Three (1.8%) out of 171 treated mothers had anti-D at the end of the second Rh-positive pregnancy, and this is 18% of the incidence in controls.Possible reasons for the occasional failure of the treatment are discussed and the results of this trial are compared with those of a previous trial in which 1,000 mug or more of anti-D was given to a different group of mothers. The combined results of the two trials lead to the conclusion that the passive administration of anti-D gammaglobulin after delivery affords in this population of Rh-negative women a 95% protection rate in the postdelivery period and an 89% protection rate by the end of the subsequent pregnancy.

Preterm premature rupture of membranes without labor is not associated with increased levels of matrix metalloproteinase-9 protein.

OBJECTIVES: Preterm premature rupture of membranes (PROM) accounts for 30-40% of all preterm births. The objectives of this study were to determine whether matrix metalloproteinase-9 (MMP-9) is increased in preterm PROM fetal membranes, whether labor or gestational age affects expression, and whether the increase is localized to the rupture site or is membrane-wide. METHODS: Fetal membranes were collected from 15 pregnancies complicated by preterm PROM and 26 control cases, which delivered at term or preterm without PROM. The preterm PROM cases represented both patients who labored and those who did not. Membrane samples at the rupture site and a remote site (approximately > 5 cm) were analyzed for MMP-9 protein and enzymatic activity by Western blot and gelatin zymography, respectively. RESULTS: MMP-9 levels in fetal membranes were similar at both the rupture and the remote sites. The highest levels of total MMP-9 protein were found in preterm PROM patients with labor (p < 0.05) and were increased four-fold over protein levels in non-laboring preterm PROM patients delivered by Cesarean section (p < 0.001). In preterm PROM patients without labor, levels of MMP-9 protein were similar to those of non-laboring patients at term and preterm. Zymography correlated with protein results in all membranes. CONCLUSIONS: Preterm PROM without labor is not associated with increased membrane levels of MMP-9 protein, suggesting that its local elevation does not play a role in early membrane rupture.