Use of monoclonal antibodies in cancer immunotherapy: types and mechanisms of action.

Immunotherapy is one of the most innovative treatments in the current field of oncology and consists of stimulating the immune system to eliminate tumoral cells. Monoclonal antibodies (mAbs) are glycoproteins secreted by B-cells capable of recognizing and neutralizing foreign organisms or antigens. Structurally, they are composed of two heavy and two light chains. The generation of therapeutic mAbs is one of the most developed and fastest-growing areas of the biotechnological and pharmaceutical industries and is an important adjunct to cancer therapy. Several antibodies have been approved for human administration and can be mouse-derived, chimeric, humanized, or fully human. mAbs main mechanism of action includes the lysis of the tumoral cells through inducing apoptosis, phagocytosis, complement activation, or signaling inhibition.

La inmunoterapia es un tratamiento innovador para la oncología actual, que consiste en la estimulación del sistema inmunitario para la eliminación de las células tumorales. Los anticuerpos monoclonales (mAbs) son glicoproteínas secretadas por los linfocitos B, capaces de reconocer y neutralizar organismos extraños o antígenos. Estructuralmente se componen de dos cadenas pesadas y dos cadenas ligeras. La generación de mAbs terapéuticos es una de las áreas de mayor crecimiento en la industria biotecnológica y farmacéutica y representa un complemento importante en la terapia del cáncer. Existen diversos mAbs que han sido aprobados para su administración en humanos, y pueden ser derivados de ratón, quiméricos, humanizados o completamente humanos. Los mecanismos de acción consisten principalmente en la lisis de las células tumorales a través de la inducción de la apoptosis, fagocitosis, activación del complemento o inhibición de la señalización celular.

Use of monoclonal antibodies in cancer immunotherapy: types and mechanisms of action / Uso de anticuerpos monoclonales en la inmunoterapia del cáncer: tipos y mecanismos de acción

Abstract Immunotherapy is one of the most innovative treatments in the current field of oncology and consists of stimulating the immune system to eliminate tumoral cells. Monoclonal antibodies (mAbs) are glycoproteins secreted by B-cells capable of recognizing and neutralizing foreign organisms or antigens. Structurally, they are composed of two heavy and two light chains. The generation of therapeutic mAbs is one of the most developed and fastest-growing areas of the biotechnological and pharmaceutical industries and is an important adjunct to cancer therapy. Several antibodies have been approved for human administration and can be mouse-derived, chimeric, humanized, or fully human. mAbs main mechanism of action includes the lysis of the tumoral cells through inducing apoptosis, phagocytosis, complement activation, or signaling inhibition.

Resumen La inmunoterapia es un tratamiento innovador para la oncología actual, que consiste en la estimulación del sistema inmunitario para la eliminación de las células tumorales. Los anticuerpos monoclonales (mAbs) son glicoproteínas secretadas por los linfocitos B, capaces de reconocer y neutralizar organismos extraños o antígenos. Estructuralmente se componen de dos cadenas pesadas y dos cadenas ligeras. La generación de mAbs terapéuticos es una de las áreas de mayor crecimiento en la industria biotecnológica y farmacéutica y representa un complemento importante en la terapia del cáncer. Existen diversos mAbs que han sido aprobados para su administración en humanos, y pueden ser derivados de ratón, quiméricos, humanizados o completamente humanos. Los mecanismos de acción consisten principalmente en la lisis de las células tumorales a través de la inducción de la apoptosis, fagocitosis, activación del complemento o inhibición de la señalización celular.

Nanophotonic Sialidase Immunoassay for Bacterial Vaginosis Diagnosis.

Bacterial vaginosis (BV) affects reproductive-age women and can lead to pelvic inflammatory disease, postpartum endometritis, and preterm labor/delivery and predisposes the infection of sexually transmitted diseases. Typically, BV diagnosis involves the analysis of vaginal swab samples via microscopy operated by highly skilled personnel. Hence, novel approaches for BV diagnosis are an existing need. In response, the first immunosensing platform targeting sialidase, a BV biomarker, is reported. The nanophotonic operational principle of this biosensing platform allows for a cheaper, faster, and simpler analysis when compared with an indirect enzyme-linked immunosorbent assay (ELISA). The clinical evaluation of such a nanotechnology is highlighted, where 162 vaginal swab samples were analyzed with high sensitivity and specificity (96.29%, respectively). The resulting nanoimmunosensing platform offers a resourceful approach to perform a timely BV diagnosis.

Production and characterization of a monoclonal antibody against the sialidase of Gardnerella vaginalis using a synthetic peptide in a MAP8 format.

Bacterial vaginosis is one of the most frequent vaginal infections. Its main etiological agent is Gardnerella vaginalis, which produces several virulence factors involved in vaginal infection and colonization, in particular, sialidase (SLD), a potential clinical biomarker that participates in immune response modulation and mucus degradation. The main objective of this work was the production and evaluation of a monoclonal antibody against G. vaginalis sialidase and its validation in immunoassays. For immunization of mice, a synthetic multiantigenic peptide was used, and hybridomas were generated. After fusion, hybridomas were evaluated for antibody production and cloned by limited dilution. One clone producing IgG1 was selected and characterized by indirect ELISA, dot blot, and Western blot, and we also tested clinical isolates and HeLa cells infected with G. vaginalis. The results showed that the anti-SLD antibody recognized a single protein of ~90 kDa that correlated with the estimated molecular weight of SLD. In addition, anti-SLD antibody recognized SLD from complete bacteria and from culture supernatants of infected Hela cells. In conclusion, our results showed that the anti-SLD antibody recognized SLD from different sources and could be considered a new tool for the diagnosis of bacterial vaginosis. KEY POINTS: • Anti-sialidase mAb was generated using a synthetic peptide • The mAb recognizes synthetic peptide and intact protein from multiple sources • The antibody was characterized by several immunological methods.

Production and characterization of monoclonal antibodies against the DNA binding domain of the RE1-silencing transcription factor.

The use of monoclonal antibodies for the detection of cellular biomarkers during carcinogenesis provides new strategies for cancer diagnosis or prognosis in patients. Loss of the Restrictive Element 1-Silencing Transcription (REST) factor has been observed in previous molecular and immunological approaches in aggressive breast cancer, small cell lung cancer, liver carcinoma, and colo-rectal cancer; however, for clinic diagnosis, monoclonal antibodies for REST recognition are unavailable. The goal of this work was to design, produce and characterize monoclonal antibodies against the REST DNA binding damain (DBD) that would be suitable for immunoassays. We searched for conserved domains, and immunogenic and antigenic sites in the REST structure via in silico analysis. For mice immunization, we used a recombinant REST DBD purified by affinity chromatography, and then Hybridomas were generated by mouse spleen fusion with myeloma cells. Finally, for monoclonal antibody characterization, we performed enzyme-linked immunosorbent (ELISA), western blot, dot blot, immunocytochemistry (ICC) and immunoprecipitation assays. Results showed that the DBD is conserved in REST isoforms and contains immunogenic and antigenic sites. We generated three clones producing monoclonal antibodies against REST DBD, one of them specifically recognized native REST and was suitable for ICC in samples from patients.

Laboratory diagnosis of human neurocysticercosis: double-blind comparison of enzyme-linked immunosorbent assay and electroimmunotransfer blot assay.

Neurocysticercosis is a common disease in underdeveloped countries. Its diagnosis is based on clinical, imaging (tomography or magnetic resonance), epidemiological, and laboratory data. Several methods based on the detection of antibodies against cysticerci in cerebrospinal fluid or serum have been tested. Among them, an enzyme-linked immunosorbent assay (ELISA) based on the use of a crude parasite antigen has been used by the laboratory network of cysticercosis in Mexico, which has given support to clinicians for up to 7 years. A Taenia solium-specific glycoprotein-based electroimmunotransfer blot (EITB) assay was reported to be highly sensitive and specific for this purpose. In order to compare both techniques, we studied 100 neurocysticercosis patients and 70 neurological noncysticercosis controls and searched for specific antibodies in paired samples of serum and cerebrospinal fluid using both techniques. We found that the EITB assay is more sensitive than the ELISA, especially when serum is being tested. Both techniques are more sensitive in cases with multiple living cysts than in cases with single cysts or calcified lesions. No global differences among cases with parasites located in different parts of the central nervous system were found. In the patients with cysts within the parenchyma, the sensitivity of the EITB assay was higher with serum than with cerebrospinal fluid. The immunodominant bands were found to be the same as those previously reported, i.e., GP-39 to -42, GP-24, and GP-13. Based on these results, we suggest the use of the EITB assay in routine diagnosis of cysticercosis for clinical cases.