[Presence of measles virus antibodies in a group of patients with malignant hemopathy]. / Presencia de anticuerpos al virus del sarampión en un grupo de pacientes con hemopatías malignas.

225 monosera from patients (121 adults and 104 children) with different malignant haemopathies from the Institute of Hematology were studied. The hemagglutination inhibition (HI) technique and the neutralization technique were used to know the presence of antimeasles antibodies. All these patients were under immunosuppression treatment at the time of taking the specimen and children had received the triple viral vaccine (measles, rubella, parotiditis) before the disease was diagnosed. It was found that 51 (42.14%) of the adults' specimens were positive by HI and of the 25 negative specimens that underwent the neutralization technique, 18 (72%) proved to be positive. Of the 104 sera corresponding to children, 31 (29.8%) specimens were positive by HI, whereas 29 of the negative were studied by neutralization. 18.34% of all the specimens continued to be negative by both methods. According with the 2 techniques used, the presence of measles virus antibodies was of 81.66% in children and of 90.78% in adults.

Evaluation of the serologic response against two consensus V3 loop peptides from human immunodeficiency virus-1 in Cuban patients.

OBJECTIVES: A retrospective study was conducted to evaluate the antibody response of Cuban patients infected with human immunodeficiency virus (HIV)-1 against two consensus peptides from the third variable domain (V3) loop of glycoprotein gp120. METHODS: The study included sera from 10 individuals at different stages of disease. Two 15-meric synthetic peptides designed from a consensus sequence, belonging to group B or C of HIV-1, were used to determine antibody titers and avidity indexes in an indirect enzyme-linked immunoassay. RESULTS: A high reactivity against both peptides was detected, with 80% of the sera reacting with at least one of the peptides. The antibody titers and avidity indexes did not correlate with disease progression. Additionally, for one of the patients from whom the virus had been isolated, a higher avidity index was found against the homologous peptide. CONCLUSIONS: This study showed high reactivity against two consensus peptides from the V3 loop of gp120 among patients with HIV. Large scale studies are needed to determine whether the titers or avidity of anti-V3 antibodies, at the early stages of infection, are predictive of disease progression. Both peptides are candidates for inclusion in experimental vaccines.

[Estimation of IgG Adenovirus antibody titers using a standard curve and an indirect ultramicroELISA essay]. / Estimación del título de anticuerpos IgG a Adenovirus utilizando una curva patrón y un ensayo de ultramicroELISA indirecto.

It was possible to standardize a procedure which combined an indirect microELISA assay with a standard curve and that allowed to estimate the titre of IgG antibodies to Adenovirus in samples of human serum, using only one dilution of these. Based on the end-point titre previously determined for a panel of 117 serum samples, we selected 90 of these samples (r2 = 0.98) to build 4 standard curves that related the natural logarithm of the fluorescence responses to the natural logarithm of the end-point titre for a wide range of serum dilutions (1:40 = 1:320). It was selected the curve corresponding to serum dilution 1:40 (r2 = 0.81), which made possible an optimum utilization of those accessories designed to handle the volumes in the ultramicro range and, therefore, the automation of the whole procedure. The results obtained as regards the complement fixation test (100% of sensitivity and 97.3% of specificity) support the use of this method in our laboratory as a complementary tool to carry out seroepidemiological studies on a large scale and with diagnostic ends.

[Indirect ultramicroELISA for the detection of total adenovirus antibodies in human serum]. / UltramicroELISA indirecto para la detección de anticuerpos totales a Adenovirus en suero humano.

An indirect ultramicroELISA method was normalized for the detection of total antibodies to Adenovirus (AD) (UMELISA AD). The optimum concentration of surface antigen determined was 30 micrograms/mL; serum dilution was of 1:40; and conjugate dilution, of 1:1,000. The UMELISA AD was compared with the complement fixing and indirect immunofluorescence techniques. Results showed accordance by 88% and 96.6%, respectively. The method is valid for the screening of antibodies in seroepidemiological studies as well as for the diagnosis of the infection by paired serum samples.