Ninguna vacuna es altamente eficaz contra la tuberculosis (TB), la enfermedad predominantemente respiratoria causada por la infección por la bacteria Mycobacterium tuberculosis ( Mtb ), que causa aproximadamente 1,3 millones de muertes al año. Cada vez hay más evidencia que sugiere que los anticuerpos pueden proteger contra la infección por Mtb, pero se desconoce el potencial de estos anticuerpos protectores.

In a paper published online on December 12, 2023, in eBiomedicina, Jacqueline Achkar, M.D., M.S., Elise Ishida, and colleagues evaluated airway and serum samples of 57 macaque monkeys that had undergone low-dose Mtb airway infection; 36 of the animals developed latent Mtb infection (i.e., no symptoms and no signs of disease), and 21 developed active TB (the disease which can be transmitted and result in death). The researchers assessed levels of several types of antibodies in the macaques before infection, 2-3 months after, and 5-6 months after infection. Compared with macaques with active TB, those with latent Mtb infection had much stronger antibody responses. More specifically, latently infected macaques had significantly increased (1) airway and plasma IgA against specific Mtb glycan antigens prior to infection; (2) plasma IgG reactivity to the Mtb protein MTB32A early post-infection; and (3) airway IgG responses to certain Mtb proteins early postinfection. The results suggest that latently infected macaques may have been protected against active infection due to pre-existing antibodies from prior exposure to non-TB-causing mycobacteria (which have been found to bolster protection against TB in experiments involving mice). If so, these findings could inform strategies for developing more effective TB vaccines.

El Dr. Achkar es profesor de medicina y de microbiología e inmunología, director de investigación en salud global en el Centro de Salud Global, director asociado de investigación traslacional en el Programa de Capacitación en Investigación Clínica (CRTP) de Einstein y médico adjunto en el Montefiore Medical Center. La primera autora del estudio es Elise Ishida, estudiante de PhD en el laboratorio del Dr. Achkar, quien se graduó recientemente.