Induction of a protective response with an IgA monoclonal antibody against Mycobacterium tuberculosis 16kDa protein in a model of progressive pulmonary infection.

Mycobacterium tuberculosis is a facultative intracellular pathogen for which cell-mediated immunity is considered the major component of the immune response. For many decades, the prevailing scientific view has been the antibodies have little or no role in modifying the course of M. tuberculosis infection. In recent years, several studies have challenged this dogma, and there is a body of evidence that supports a role of antibodies against M. tuberculosis. In the present work, we evaluated the protective activity of two monoclonal antibodies (TBA61 and TBA84). Here, we chose the intratracheal model of pulmonary infection to evaluate bacterial load and morphometric and histological changes in the lungs of treated mice. Data obtained revealed the reduction of bacterial load and milder morphometric and histopathological changes in mice treated with TBA61 at 21 days post-infection with M. tuberculosis H37Rv compared to those treated with TBA84 and control mice. These results allow continuing exploring the potential use of monoclonal antibodies as prophylactic and therapeutic agents against intracellular pathogens such as M. tuberculosis.

[Prevention of infections in patients with lymphoproliferative syndromes and myeloma by nebulization of an IgA concentrate]. / Prevención de infecciones en pacientes con síndromes linfoproliferativos y mieloma por nebulización de un concentrado de IgA.

Infection of the upper respiratory tract is a major cause of morbidity and mortality in patients with lymphoproliferative syndromes and multiple myeloma. Nebulizations with IgA tested in a randomized double blind trial to evaluate its efficacy to prevent respiratory infections in patients with lymphoproliferative syndromes and multiple myeloma. Forty nine patients were evaluated (chronic lymphocytic leukaemia, 22; multiple myeloma, 11; lymphoma, 8; HCL, 6; Waldenström and lymphoepiteliod tymoma, 1 patient each) were randomized to receive nebulizations every 12 hours during 3 months of IgA or placebo. Seven infectious episodes (4 respiratory tract infections) in 25 IgA treated patients and 25 episodes (16 respiratory tract infections) in 24 control patients were recorded (p <0.0002). Eighteen patients belonging to the treated group remained free of infections against only 5 from the control group (p < 0.001). No difference related to the grade of infections was observed between groups. The arithmetic media for the first infection observed in each group was 45.6 +/- 22.0 days for the IgA treated and 28.6 +/- 17.5 days for the placebo (p < 0.025). According to this study, IgA nebulization therapy was useful to prevent respiratory tract infections and also delay the onset of infection in patients with lymphoproliferative syndromes and myeloma.

[Treatment with human colostrum of children with prolonged infectious gastroenteritis]. / Tratamiento con calostro humano a niños con gastroenteritis infecciosa prolongada

The results of treatment with human colostrum in 6 babies with protracted infectious diarrhea from enteropathogenic E. coli and/or Salmonella are reported. Active diarrhea was present in 5 cases and the 6th was a carrier. Remission was obtained in cases with diarrhea and all showed increase in weight. Negativeness of stool cultures was achieved in four cases and in the other two, the bacteriologic control was not complete. One patient died from a secondary pulmonary infectious problem. As an average, all patients showed rise in secretory IgA and in IgG measured at the duodenal fluid level and in comparison with a control group, there were statistically significant differences. Serum immunoglobulins showed no changes following administration of human colostrum. Although the number of patients reported is small, the results obtained may be considered favorable.