Exploration of Immunology

Table 1. Sex hormones regulate immune response [6, 7, 10, 11].

Hormone	Mechanism of action	General immunological effect
Oestrogen	Increases B cell proliferation, class switching to immunoglobulin (Ig)G, T helper (Th)2, and T regulatory (Treg) cell responses; modulates Treg transcriptional programs	Immune-enhancing; promotes humoral responses
Progesterone	Induces anti-inflammatory molecules; inhibits Th1 and Th17 pathways; modulates antigen presenting cells (APCs) activation	Immunosuppressive; anti-inflammatory
Testosterone	Reduces pro-inflammatory cytokines [interleukin (IL)-1β, IL-6, tumour necrosis factor (TNF)]; increases IL-10; inhibits T cell proliferation; suppresses B cells and natural killer cytotoxicity	Immunosuppressive; anti-inflammatory
Prolactin	Promotes B cell activation and antibody production; upregulates costimulatory molecules on APCs; modulates Th1/Th2 cytokines	Immune-enhancing

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Author contributions

AC: Investigation, Writing—original draft, Writing—review & editing. AA: Writing—review & editing. EM: Writing—review & editing. GP: Writing—review & editing. CMT: Conceptualization, Investigation, Writing—original draft, Writing—review & editing, Supervision. CC: Conceptualization, Investigation, Writing—original draft, Writing—review & editing, Supervision. All authors read and approved the submitted version.

Conflicts of interest

Calogero Caruso, who is the Editor-in-Chief of Exploration of Immunology, had no involvement in the decision-making or review process of this manuscript. Emanuele Montomoli is the founder and Chief Scientific Officer of VisMederi srl. The other authors declare that they have no conflicts of interest.

Ethical approval

Not applicable.

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This research received no external funding.

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