Tumor regressions observed in patients with metastatic melanoma treated with an antigenic peptide encoded by gene MAGE-3 and presented by HLA-A1

Thirty-nine tumor-bearing patients with metastatic melanoma were treated with 3 subcutaneous injections of the MAGE-3.A1 peptide at monthly intervals. No significant toxicity was observed. Of the 25 patients who received the complete treatment, 7 displayed significant tumor regressions. All but one of these regressions involved cutaneous metastases. Three regressions were complete and 2 of these led to a disease-free state, which persisted for more than 2 years after the beginning of treatment. No evidence for a cytolytic T lymphocyte (CTL) response was found in the blood of the 4 patients who were analyzed, including 2 who displayed complete tumor regression. Our results suggest that injection of the MAGE-3.A1 peptide induced tumor regression in a significant number of the patients, even though no massive CTL response was produced.

Derivation of tumor-specific cytolytic T-cell clones from two lung cancer patients with long survival

We derived lung carcinoma cell lines from tumor material resected from a patient with small-cell lung cancer (SCLC) and from a patient with non-small-cell lung cancer (NSCLC). The patient with NSCLC was vaccinated with irradiated autologous tumor cells. The two patients enjoyed an exceptionally favorable clinical evolution and are currently without signs of cancer 10 and 8 yr after their diagnoses, respectively. Autologous mixed lymphocyte-tumor cell cultures (MLTC) were produced with blood lymphocytes stimulated with irradiated autologous tumor cells. The first patient's SCLC cells, which carried a small amount of human leukocyte antigen (HLA) class I molecules, were incubated with interferon-gamma (IFN-gamma) before being used as stimulator cells. A cytolytic T-lymphocyte (CTL) clone was derived that specifically lysed the IFN-gamma-treated SCLC cells but did not lyse untreated tumor cells or autologous lymphoblasts. Clones of autologous tumor-specific CTL, directed against the NSCLC cells of the other patient, were also obtained. These tumor cells carried a higher level of HLA class I molecules and were lysed by the CTL without incubation with IFN-gamma. Altogether, these results indicate that SCLC and NSCLC cancer cells can be recognized by autologous CTL, and might therefore be susceptible to specific immunotherapy.

T-DNA mediated disruption of essential gametophytic genes in Arabidopsis is unexpectedly rare and cannot be inferred from segregation distortion alone

Many genes are thought to be expressed during the haploid phase in plants, however, very few haploid-specific genes have been isolated so far. T-DNA insertion mutagenesis is a powerful tool for generating mutations that affect gametophyte viability and function, as disruption of a gene essential for these processes should lead to a defect in the transmission of the gametes. Mutants can therefore be screened on the basis of segregation distortion for a reporter resistance gene contained in the T-DNA. We have screened the Versailles collection of Arabidopsis transformants for 1:1 KanR:KanS segregation after selfing, focussing on gametophyte mutations which show normal transmission through one gametophyte and cause lethality or dysfunction of the other. Only 1.3% (207) of the 16,000 lines screened were scored as good candidates. Thorough genetic analysis of 38 putative T-DNA transmission defect lines (Ttd) identified 8 defective gametophyte mutants, which all showed 0 to 1% T-DNA transmission through the pollen. During the screen, we observed a high background of low-penetrance mutations, often affecting the function of both gametophytes, and many lines which were likely to carry chromosomal rearrangements. The reasons for the small number of retained lines (all male gametophytic) are discussed, as well as the finding that, for most of them, residual T-DNA transmission is obtained through the affected gametophyte.

Mutations of the beta2-microglobulin gene result in a lack of HLA class I molecules on melanoma cells of two patients immunized with MAGE peptides

Mutations have been identified in the beta2-microglobulin gene of tumor cells of two metastatic melanoma patients who received immunizations with MAGE peptides. One mutation abolishes the start codon whereas the other introduces a premature stop codon. The second beta2-microglobulin allele of both tumors appears to be lost on the basis of sequence data and loss of microsatellite heterozygosity. The lack of beta2-microglobulin gene product results in the absence of HLA class I antigens on the surface of the tumor cells. This may explain why the tumors of both patients progressed despite the immunization treatment and shows the necessity of analyzing in depth the antigen presentation capability of the tumor cells for the interpretation of clinical trials involving anti-tumor vaccination.

Twelve-year experience with Carpentier-Edwards PERIMOUNT pericardial valve in the mitral position: a multicenter study

BACKGROUND AND AIMS OF THE STUDY

The study aim was to assess the durability of the Carpentier-Edwards PERIMOUNT pericardial bioprosthesis in the mitral position.

METHODS

This seven-center retrospective clinical study involved the follow up of 333 patients who underwent isolated mitral valve replacement and 102 patients who underwent double (mitral and aortic) valve replacement with the PERIMOUNT pericardial valve between 1984 and 1989. Mean patient age at implant was 60.7 +/- 11.6 years; 41.1% were males. The most common etiology was rheumatic heart disease (53.9%) and the most common mechanism mitral insufficiency. All patients but six were followed for an average of 7.2 +/- 3.6 years after surgery; total follow up was 3071.7 patient-years (pt-yr).

RESULTS

The total operative mortality rate was 7.6%; this included a valve-related mortality rate of 0.2%. The late mortality rate was 5.2% per pt-yr, of which 1.4% per pt-yr was considered valve-related. At 11 years, the overall actuarial survival rate was 53.3 +/- 2.8%, and actuarial freedom from valve-related death 83.9 +/- 2.6%. At follow up, 80% of patients were in NYHA class I or II, and 74% showed improvement. Twenty-eight incidences of deterioration requiring explant were observed. At 11 years the actuarial freedom from explant due to structural failure was 84.9 +/- 3.1%. Rates of structural failure decreased with age: the actuarial freedom from explant due to structural failure was 78.1 +/- 4.8% for patients aged < or = 60 years, 89.4 +/- 4.4% for those aged 61-70 years, and 100% for those aged over 71 years.

CONCLUSION

The Carpentier-Edwards PERIMOUNT pericardial bioprosthesis is a reliable choice when a tissue valve is required, especially in patients over 60 years of age.

[Clinical, hemodynamic and angiographic results of total cavo-pulmonary connection]

The aim of the study was to assess the short and medium term results of total cavo-pulmonary connection based on analysis of the functional status, the cavo-pulmonary circulation and the surgical techniques, and the hepatic consequences. Fifteen patients with congenital defects beyond repair were treated by total cavo-pulmonary connection at Tours between March 1st 1992 and July 30th 1996. There were 12 children (mean age: 6.3 years) and 3 adults aged 25 to 28. Results were assessed by clinical examination, hepatic function tests and cardiovascular investigations including right heart catheterisation with angiography in 14 patients. There were no fatalities. Seven patients were in functional Class I and 8 in Class II at medium term (average follow-up of 33 months). Hepatic function was mildly abnormal in all patients with an increase in serum bilirubin and gamma GT, and a decrease in the coagulation factors. The mean pressures in the atrial channel were 12 mmHg (9-16 mmHg), in the superior vena 13.2 mmHg (10-18 mmHg), in the right pulmonary artery 9.5 mmHg (7-15 mmHg) and 11.6 mmHg (8-16 mmHg) in the left pulmonary artery. Significant residual stenosis of a pulmonary branch was observed in 2 cases. The cavo-pulmonary anastomoses were out of line, one from the other, in all cases. The atrial channel was tubular in 9 cases and dilated with slight stagnation of the contrast medium in its inferior region in 5 cases. Total cavo-pulmonary connection transformed the clinical status of these patients but was associated with minor abnormalities of liver function. The quality of the cavo-pulmonary circulation and the surgical anastomoses was estimated to be satisfactory in the majority of cases.

[Echocardiographic Doppler study of left ventricular filling in the diagnosis of minimal or moderate rejection in cardiac transplantation]

The study of left ventricular filling by Doppler echocardiography may be a non-invasive diagnostic method of detection of acute rejection of cardiac transplants. The aim of this study was to assess the value of the method for diagnosis of minimal to moderate rejection (grades 1 to 3 of the Billingham classification). A total of 466 Doppler echocardiographic studies were performed in 23 cardiac transplantation patients (21 men, mean age 49.3 +/- 10 years) with endomyocardial biopsy as the reference method for the diagnosis of rejection. Over a follow-up period of 18.5 +/- 10 months, 22.7% of biopsies showed minimal or moderate rejection. The Doppler measurements of the isovolumic relaxation period and peak early diastolic (E) velocity with respect to the mitral velocity-time integral were no different in cases of acute rejection. The only difference observed was in the mitral half-pressure time which was much shorter in cases of rejection. However, after drawing a ROC graph, the accuracy of this parameter was insufficient for diagnosing rejection irrespective of the threshold of variation considered (23% sensitivity for a 20% shortening and 36% sensitivity for a 10% shortening). The authors conclude that Doppler echocardiographic study of left ventricular filling is of limited value for the diagnosis of acute minimal or moderate rejection in cardiac transplant patients. The half-pressure time may be a useful complement to endomyocardial biopsy or when biopsy investigations are performed less frequently.

The single-breath nitrogen test in coal miners: factors associated with failure to perform

The single-breath nitrogen washout (SBN2) test was used, along with spirometry, in the baseline examination of a longitudinal study in a cohort of active coal miners from North-eastern France. The procedure was computerized, allowing the technician to coach and encourage the subject, and excluding computation errors. While all miners performed satisfactory spirometry, a significant number were unable to meet the National Heart and Lung Institute recommendation concerning a 10% agreement of vital capacities. When the limits were set at +/-12%, 57 miners (24.2%) were still classified as failing to perform. When compared to those who succeeded, those failing proved to be significantly older, had more cumulated dust exposure, a higher prevalence of chronic cough and sputum, and a trend for more micronodulation on the chest radiographs. The ventilatory function did not differ between the two groups. These results confirm previous data on spirometric test failure concerning older age and respiratory symptoms, extending them to the SBN2 test. The present study further indicates that dust exposure and roentgenologic pneumoconiosis nodulation are associated with failure to perform the SBN2 test.

Real time validation of paediatric biochemical reports using the Valab-Biochem system

Validation of biochemical reports must be fast and clinically accurate to be of assistance to clinicians. Considerable skill is required to analyse the consistency of different data in the report and to consider influences on the data. When performed throughout the day, such analysis is time-consuming and uncertain. We therefore decided to use a computer-assisted validation system, Valab-Biochem. Its decisions result from a decision tree based primarily on the intrinsic consistency of the data, validation ranges and patients' sex, age and hospital ward. Three hundred randomly chosen reports were simultaneously submitted to Valab-Biochem and to five biologists in order to analyse the computer's findings. The sensitivity of Valab-Biochem was 80% compared to biologists' consensus decision, which was taken as the gold standard. The specificity was 78%. This system provided autonomous assessment of the reports and could be used as an initial screen to assist biologists and focus attention on potentially inconsistent reports.

Influence of age on valve related events with Carpentier-Edwards pericardial bioprosthesis

Age is the most important factor for the durability of biological valves. With an original design the Carpentier-Edwards pericardial valve showed improved results at 10 years. The influence of age on valve related complications is studied with a 10 year follow up on 807 valvular replacements.

METHODS

Between January 1984 and December 1993, 807 patients underwent valve replacements with a Carpentier-Edwards pericardial bioprosthesis. Patients, 193 were younger than 60 years, 284 between 60 and 70 years and 330 patients were older than 70 years. All patients but seven were followed up for an average of 4.18 years after their operation and total follow up was 3373 patient years. Patients were divided into three groups of age: group I, less than 60 years; group II, 60-70 years; group III, over 70 years. A retrospective comparison was made between age groups.

RESULTS

At 11 years, valve related complications included 97 patients with 27 valve related deaths. Rates of valve related death increase with age linearized rate were 0.3, 0.6 and 1.2%, respectively. No difference was observed for rates of all valve related morbidity: 2.6, 2.4 and 3.5%, respectively. Risk of thromboembolism increased with age, linearized rates were: 0.3, 0.7 and 1.3%. Risk of deterioration and reoperation decreased with age, rates of deterioration were 0.8, 0.1 and 0%. Other valve related events had the same incidence in all groups. No statistical difference was observed between group II and group III for deteriorations and reoperations.

CONCLUSIONS

The performance of the Carpentier-Edwards pericardial valve is the same at 10 years in group II and III. This study supports the clinical use of this tissue valve in patients over 60 years. The results in group I are satisfactory, nevertheless, a more durable biological valve is needed for young patients.

[Intermediary results with the CarboMedics bileaflet valvular prosthesis]

From December 1988 to December 1995, 212 patients underwent valve replacement with a CarboMedics bileaflet valve in our institution (103 aortic valve replacements, 72 mitral valve replacements, and 37 double valve replacements). Fifty-five percent were male patients. Mean age was 53.8 +/- 12.7 years. Forty seven percent of patients were in NYHA clinical status III or IV. Operative mortality was 3.7% (8/212). All patients but eight were followed-up for an average of 2.9 years after their operation and total follow-up was 617 patient-years. At the time of the study, more than 90% of patients were in NYHA class I or II, 26% were in atrial fibrillation and 100% of patients received anticoagulation treatment. There were 15 late deaths. After 7 years, the actuarial survival rate was 84 +/- 7%. Three patients died of valve-related causes. Valve-related complications included 5 thromboembolic episodes (0.8% patient-year), 18 anticoagulant-related complications (2.9% patient-years), 3 endocarditis (0.5% patient-year), and 4 reoperations (0.6% patient-year). After 7 years, freedom from thrombo-embolic complication was 97 +/- 2%, from anticoagulant-related complications was 88 +/- 6%, from endocarditis was 96 +/- 4%, and from reoperation was 95 +/- 5%. We conclude that the 7-year results compare with other bileaflet valves. More follow-up and larger studies are mandated to give definite conclusions.

[Treatment of congenital heart diseases with pulmonary artery cerclage. Immediate and medium term results in 51 patients]

The aim of this study was to assess the results of pulmonary artery banding in a retrospective study of 51 consecutive children treated from January 1980 to December 1993. The study population was 24 girls and 27 boys with an average age of 6.2 months, of average weight of 4.01 kg. The cardiac conditions treated were ventricular septal defects in 24 cases (isolated and associated with one or more cardiovascular malformations or multiple), complete atrioventricular canal in 12 cases (isolated or associated with several cardiovascular malformations), single ventricle in 7 cases, double outlet right ventricle in 3 cases, transposition of the great arteries with ventricular septal defect in 2 cases, tricuspid atresia in 2 cases, and a complex lesion with double discordance in one case. The average duration of banding was 2.35 years (n = 49). Hospital morality of banding was 1.9% (1/51). Late mortality was 14.8% (7/47). Twenty-one patients (42.8%) had complications of banding. The survival rates of children who underwent banding was 86.8% at 1 year and 80.6% at 11 years. The low hospital mortality leaves a role for pulmonary artery banding as a palliative procedure in congenital heart disease in which early correction is impossible or carries and unacceptable risk. Complications of banding justify attempts to improve the technique, by making adjustable bands.

A preliminary evaluation of a recombinant circumsporozoite protein vaccine against Plasmodium falciparum malaria. RTS,S Malaria Vaccine Evaluation Group

BACKGROUND

The candidate vaccines against malaria are poorly immunogenic and thus have been ineffective in preventing infection. We developed a vaccine based on the circumsporozoite protein of Plasmodium falciparum that incorporates adjuvants selected to enhance the immune response.

METHODS

The antigen consists of a hybrid in which the circumsporozoite protein fused to hepatitis B surface antigen (HBsAg) is expressed together with unfused HBsAg. We evaluated three formulations of this antigen in an unblinded trial in 46 subjects who had never been exposed to malaria.

RESULTS

Two of the vaccine formulations were highly immunogenic. Four subjects had adverse systemic reactions that may have resulted from the intensity of the immune response after the second dose, which led us to reduce the third dose. Twenty-two vaccinated subjects and six unimmunized controls underwent a challenge consisting of bites from mosquitoes infected with P. falciparum. Malaria developed in all six control subjects, seven of eight subjects who received vaccine 1, and five of seven subjects who received vaccine 2. In contrast, only one of seven subjects who received vaccine 3 became infected (relative risk of infection, 0.14; 95 percent confidence interval, 0.02 to 0.88; P<0.005).

CONCLUSIONS

A recombinant vaccine based on fusion of the circumsporozoite protein and HBsAg plus a potent adjuvant can protect against experimental challenge with P. falciparum sporozoites. After additional studies of protective immunity and the vaccination schedule, field trials are indicated for this new vaccine against P. falciparum malaria.

The majority of autologous cytolytic T-lymphocyte clones derived from peripheral blood lymphocytes of a melanoma patient recognize an antigenic peptide derived from gene Pmel17/gp100

Anti-melanoma cytolytic T-lymphocyte (CTL) clones were derived from peripheral blood lymphocytes of HLA-A2 melanoma patient LB265 after stimulation with the autologous tumor cell line LB265-MEL, which showed high expression of melanocyte-lineage specific genes. Of 55 CTL clones, 46 recognized HLA-A2-restricted antigens. These 46 CTL clones were studied for their ability to specifically release tumor necrosis factor in the presence of COS cells cotransfected with the HLA-A2 gene and the cDNA of either tyrosinase, Melan-A/MART1, Pmel17/gpl00, gp75/TRP1, or MSH receptor. Six CTL clones recognized the Melan-A/MART1 antigen, whereas the remaining 40 CTL clones recognized a Pmel17/gp100 antigen. These 40 anti-PmelI7/gpl00 CTL clones were all able to lyse T2 cells pulsed with the antigenic peptide YLEPGPVTA, as previously reported. The T-cell receptor beta chain hypervariable region was sequenced and found to be identical in the 15 CTL clones analyzed. Taken together, these data show a high frequency of Pmell7/gp100-specific T cells in autologous antitumor CTL clones derived from peripheral blood of a melanoma patient.

Infrequent expression of the MAGE gene family in uveal melanomas

It has previously been reported that MAGE-1, -2, -3 and -4 genes are expressed in human cancers including cutaneous melanoma. MAGE-1 and MAGE-3 represent targets for specific immunotherapy because they encode peptide antigens which are recognised by cytotoxic T lymphocytes (CTL) when presented by HLA class I molecules, and pilot clinical trials with these peptides are currently in progress. It is likely that other members of the MAGE gene family may also encode antigens recognised by CTL. Uveal melanomas, like cutaneous melanomas, arise from melanocytes that are derived from the neural crest. To determine if uveal melanoma patients would be suitable for MAGE-peptide immunotherapy, the expression of MAGE-1, -2, -3 and -4 genes was assessed by reverse transcription followed by polymerase chain reaction (RT-PCR) amplification and ethidium bromide staining. Expression of MAGE genes was not detected in any of 27 primary tumours. Either MAGE-1 or MAGE-4 was expressed in only 2 of 26 metastatic samples, but expression of MAGE-2 or -3 was not detected. Our data suggest that, unlike cutaneous melanomas, uveal melanomas may not be suitable candidates for MAGE-peptide immunotherapy.

Pericardial valves in small aortic annuli: ten years' results

OBJECTIVE

The first generation of pericardial valves was withdrawn from the market because of too high a rate of premature failure. With an original design, the Carpentier-Edwards pericardial valve promised improved results, especially in small sizes.

METHODS

Ninety patients who underwent an isolated aortic valve replacement with a 19 mm Carpentier-Edwards pericardial bioprosthesis in our institution between July 1984 and December 1993 were followed up. The mean age was 72.2 +/- 10.1 years. Fifty percent of the patients were in NYHA clinical status III or IV. The operative mortality rate was 3.7% (3/90). All patients were followed up for an average of 4.45 years after their operation and the total follow-up was 398 patient-years.

RESULTS

At this time of the study, over 80% of the patients are in NYHA class I or II. There were nine late deaths. After 10 years the actuarial survival rate was 80 +/- 12%. Three patients died of valve-related causes (1 endocarditis, 1 structural failure and 1 sudden death). The actuarial rate of freedom from valve-related death was 93 +/- 6% at 10 years. Valve-related complications included two thromboembolic episodes (0.5% patient-year), one endocarditis (0.3% patient-year), one reoperation (0.3% patient-year) and one structural valve failure with calcification and stenosis (0.3% patient-year). After 10 years, freedom from reoperation was 99 +/- 1%, from valve failure 98 +/- 2%, from thromboembolic episodes 95 +/- 4% and from endocarditis 98 +/- 2%. The mean gradient was 18.8 mmHg and mean effective orifice area 1.1 cm2.

CONCLUSIONS

With a low rate of valve-related events at 10 years and a low rate of structural deterioration with no leaflet tear, this prosthesis is a reliable alternative for small aortic annuli.