Alex Sierra Marrero
Alex Sierra Marrero
DOCTORAL CANDIDATE
Chemical Immunology Lab
Address: Bizkaia Science and Technology Park, building 801A, Derio (Bizkaia)

The clinical success of anticancer and antiviral vaccines often requires co-administration of an adjuvant, a substance that enhances the immunogenicity of the antigen and potentiates the immune response. However, few adjuvants exhibit sufficient potency and negligible toxicity to be suitable for clinical use; moreover, their mechanisms of action are generally not fully understood. Current subunit vaccines based on weakly immunogenic carbohydrate and glycopeptide antigens are not being very successful in eliciting a strong immune response against cancer, and no such carbohydrate-based anticancer vaccine has yet been approved for humans despite extensive research efforts and several clinical trials. In this context, building upon the PI's previous background and expertise in the area, the research program in the Fernández-Tejada Group has a double, ultimate goal based on applying chemistry to address the above clear gaps in the adjuvant/vaccine field. With this idea in mind, the Chemical Immunology Lab established by Dr. Fernández-Tejada at CIC bioGUNE will develop new improved adjuvants and novel chemical strategies towards more effective, self-adjuvanting synthetic vaccines. Moreover, leveraging the extraordinary facilities and scientific expertise available at CIC bioGUNE, we will also focus on investigating the molecular mechanisms of the synthetic constructs by combining extensive immunological evaluations with molecular target identification studies and detailed conformational analysis. Thus, the Fernández-Tejada Group builds upon a highly multidisciplinary program integrating ambitious objectives and complementary approaches at the chemistry-biology frontier. Research in the Chemical Immunology Lab connects chemical synthesis and chemical/structural biology with cellular and molecular immunology to explore key unresolved mechanistic questions in the adjuvant/vaccine arena with extraordinary chemical precision.

The Fernández-Tejada Lab is funded primarily by the European Research Council through an ERC Starting Grant, which provides €1.5 million funding for a transformative and timely research program aimed at developing novel synthetic self-adjuvanting vaccines with improved properties and efficacy, as well as unraveling the molecular basis and three-dimensional structure underlying the biological activity of these constructs.

Latest Publications

Development of synthetic, self-adjuvanting, and self-assembling anticancer vaccines based on a minimal saponin adjuvant and the tumor-associated MUC1 antigen

Pifferi, C; Aguinagalde, L; Ruiz-de-Angulo, A; Sacristán, N; Baschirotto, PT; Poveda, A; Jiménez-Barbero, J; Anguita, J; Fernández-Tejada, A;

CHEMICAL SCIENCE

2023-03-01

Chemical biology tools to interrogate the roles of O-GlcNAc in immunity

Saha, A; Fernández-Tejada, A;

FRONTIERS IN IMMUNOLOGY

2023-01-26

Novel Oxime-Derivatized Synthetic Triterpene Glycosides as Potent Saponin Vaccine Adjuvants

Fuentes, R; Aguinagalde, L; Pifferi, C; Plata, A; Sacristan, N; Castellana, D; Anguita, J; Fernandez-Tejada, A;

FRONTIERS IN IMMUNOLOGY

2022-05-06

Design, synthesis, and initial immunological evaluation of glycoconjugates based on saponin adjuvants and the Tn antigen

Fuentes, R; Aguinagalde, L; Sacristán, N; Fernández-Tejada, A;

CHEMICAL COMMUNICATIONS

2021-10-14

Advances in chemical probing of protein O-GlcNAc glycosylation: structural role and molecular mechanisms

Saha, A; Bello, D; Fernández-Tejada, A;

CHEMICAL SOCIETY REVIEWS

2021-08-02

Rational Vaccine Design in Times of Emerging Diseases: The Critical Choices of Immunological Correlates of Protection, Vaccine Antigen and Immunomodulation

Schijns, V; Majhen, D; van der Ley, P; Thakur, A; Summerfield, A; Berisio, R; Nativi, C; Fernández-Tejada, A; Alvarez-Dominguez, C; Gizurarson, S; Zamyatina, A; Molinaro, A; Rosano, C; Jakopin, ...

PHARMACEUTICS

2021-04-01

Replacing the Rhamnose-Xylose Moiety of QS-21 with Simpler Terminal Disaccharide Units Attenuates Adjuvant Activity in Truncated Saponin Variants

Fuentes, R; Ruiz-de-Angulo, A; Sacristán, N; Navo, CD; Jiménez-Osés, G; Anguita, J; Fernández-Tejada, A;

CHEMISTRY-A EUROPEAN JOURNAL

2021-02-04

Natural and synthetic carbohydrate-based vaccine adjuvants and their mechanisms of action.

Pifferi, Carlo; Fuentes, Roberto; Fernandez-Tejada, Alberto;

Nature reviews. Chemistry

2021-01-25

Natural and synthetic carbohydrate-based vaccine adjuvants and their mechanisms of action

Pifferi, C; Fuentes, R; Fernández-Tejada, A;

NATURE REVIEWS CHEMISTRY

2021-01-25

Therapeutic Pretargeting with Gold Nanoparticles as Drug Candidates for Boron Neutron Capture Therapy

Feiner, IVJ; Pulagam, KR; Gómez-Vallejo, V; Zamacola, K; Baz, Z; Caffarel, MM; Lawrie, CH; Ruiz-de-Angulo, A; Carril, M; Llop, J;

PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION

2020-09-23

Modulation of immune responses using adjuvants to facilitate therapeutic vaccination

Schijns, V; Fernández-Tejada, A; Barjaktarovic, Z; Bouzalas, I; Brimnes, J; Chernysh, S; Gizurarson, S; Gursel, I; Jakopin, Z; Lawrenz, M; Nativi, C; Paul, S; Pedersen, GK; Rosano, C; Ruiz-de-Angulo, ...

IMMUNOLOGICAL REVIEWS

2020-06-28

Chemical synthesis and immunological evaluation of new generation multivalent anticancer vaccines based on a Tn antigen analogue

Pifferi, C; Ruiz-de-Angulo, A; Goyard, D; Tiertant, C; Sacristán, N; Barriales, D; Berthet, N; Anguita, J; Renaudet, O; Fernández-Tejada, A;

CHEMICAL SCIENCE

2020-05-07

Exploiting structure-activity relationships of QS-21 in the design and synthesis of streamlined saponin vaccine adjuvants

Ghirardello, M; Ruiz-de-Angulo, A; Sacristan, N; Barriales, D; Jiménez-Barbero, J; Poveda, A; Corzana, F; Anguita, J; Fernández-Tejada, A;

CHEMICAL COMMUNICATIONS

2020-01-16

β-Glucan as an immune activator and a carrier in the construction of a synthetic MUC1 vaccine

Wang, HX; Yang, B; Wang, YL; Liu, F; Fernández-Tejada, A; Dong, SW;

CHEMICAL COMMUNICATIONS

2019-01-07

Design, synthesis and evaluation of optimized saponin variants derived from the vaccine adjuvant QS-21

Fernández-Tejada, A;

PURE AND APPLIED CHEMISTRY

2017-09-01

Antibodies Against Specific MUC16 Glycosylation Sites Inhibit Ovarian Cancer Growth

Rao, TD; Fernández-Tejada, A; Axelrod, A; Rosales, N; Yan, XJ; Thapi, S; Wang, A; Park, KJ; Nemieboka, B; Xiang, JY; Lewis, JS; Olvera, N; Levine, DA; Danishefsky, SJ; Spriggs, DR;

ACS CHEMICAL BIOLOGY

2017-08-01

Quillaja saponin variants with central glycosidic linkage modifications exhibit distinct conformations and adjuvant activities

Walkowicz, WE; Fernández-Tejada, A; George, C; Corzana, F; Jiménez-Barbero, J; Ragupathi, G; Tan, DS; Gin, DY;

CHEMICAL SCIENCE

2016-01-01

Glycans in Medicinal Chemistry: An Underexploited Resource

Fernández-Tejada, A; Cañada, FJ; Jiménez-Barbero, J;

CHEMMEDCHEM

2015-08-01

Recent Developments in Synthetic Carbohydrate-Based Diagnostics, Vaccines, and Therapeutics

Fernández-Tejada, A; Cañada, FJ; Jiménez-Barbero, J;

CHEMISTRY-A EUROPEAN JOURNAL

2015-07-20

Conformational Analysis of Peptides and Glycopeptides Derived from the Consensus Sequence for β-O-Glucosylation

Somovilla, VJ; Martínez-Sáez, N; Fernández-Tejada, A; de la Torre, BG; Andreu, D; Jiménez-Barbero, J; Asensio, JL; Avenoza, A; Busto, JH; Corzana, F; Peregrina, JM;

CURRENT TOPICS IN MEDICINAL CHEMISTRY

2014-01-01