LABORATORY RESEARCH INTEREST
Myosins are a family of motor proteins whose role in muscle contraction and mobility in a wide range of eukaryotic cells has been extensively studied. These proteins have been extensively characterized. Much is known about their function in different cell types; little is known about these molecules in hematopoietic cells. The myosins expressed by the immune response cells participate in maintaining the tension of the plasma membrane, in the transport of secretory vesicles, in the endo and exocytosis processes, and in promoting adherence and motility of the cells. In the laboratory, we are interested in understanding the role of class 1 myosins in lymphocytes, emphasizing the emerging role of these molecular motors in the functions of the immune response.
Primary immunodeficiencies (PID) are a diverse group of more than 300 genetic disorders that fundamentally affect the immune system's development and functionality. Most of them are monogenic disorders, but the spectrum of PIDs is constantly expanding to identify new immunodeficiency syndromes through the generation of sequencing technologies and better clinical knowledge. Patients classically present with increased susceptibility to infections or infections by unusual microorganisms may also develop autoimmunity or autoinflammatory disease and neoplasms. Although supportive treatments are effective for many of these conditions, the more serious ones require early definitive treatment using a hematopoietic stem cell transplant to prevent chronic morbidity and premature mortality. The study of these conditions in Mexico is developing. Our group (made up mainly of researchers from the National Institute of Pediatrics and our laboratory) has taken on the task of identifying and characterizing both clinically and molecularly these patients. We hope to contribute with these studies to a better diagnosis, which may result in a timely and better-targeted treatment; Additionally, we hope to learn from these patients the molecular determinants that control the immune system's various functions in a natural environment. Using a complementary approach, we studied mice deficient in some of the molecules described as causing PIDs to better understand their role.
The immunological experience that the mother has accumulated plays an essential role in protecting the newborn through the maternal transfer of IgA present in colostrum and milk. Most of the area's work has been limited to determining total IgA levels without differentiating between IgA1 and IgA2. In our laboratory, we have given ourselves the task of quantifying the levels of immunoglobulins in Mexican mothers' colostrum, using the quantitative ELISA technique, with emphasis on the levels of IgA1 and IgA2. The results so far indicate a correlation between the levels of IgA1 in the colostrum of women with respiratory tract and skin infections. In contrast, IgA2 was elevated in the colostrum of women who had gastrointestinal tract infections during pregnancy.
In conclusion, the presence of infections during pregnancy increases the levels of IgA in colostrum. This increase is dependent on the site of induction of the response, being different between the respiratory mucosa, where the response by IgA1 predominates in colostrum, and the digestive mucosa, where the increase observed is with IgA2. These data provide evidence to understand the effect of immunizations and infections during pregnancy that a clinically healthy woman can usually present. This information gives us an idea of the possible effects it would have on protecting the newborn and the individual role of IgA subtypes in maternal transfer. More recently, we have begun studying the colostrum microbiota and its association with IgA, looking for how these antibodies can impact the establishment of the newborn's intestinal microbiota.
Finally, derived from the COVID-19 pandemic, we have established quantitative methods to evaluate the presence of antibodies against this virus, seeking to contribute to the diagnosis and a better understanding of immunity in this disease.
https://www.facebook.com/INCICh.edu/videos/1199810900411209/ (May 27th, 2020)
https://youtu.be/eGq3BpjfbGY (July 8th, 2020)
https://youtu.be/4w9pSuPGvN8 (July 13th, 2020)
https://youtu.be/8Zf1Hn-ollM (November 16th, 2020)
https://youtu.be/ylgLGgcMLSI (February 17th, 2021)
https://avanceyperspectiva.cinvestav.mx/author/leopoldo-santos-argumedo/ (March 13th, 2021)