Vaccine
Volume 40, Issue 11, Pages 1513-1680 (8 March 2022)
https://www.sciencedirect.com/journal/vaccine/vol/40/issue/11

Optimmunize: Improving the Beneficial Effects of Vaccines
Editorial Full text access
Introduction
Eleanor N. Fish, Christine S. Benn, Sabra L. Klein
There is increasing evidence that vaccines, in addition to their disease-specific effects, have important off-target or non-specific effects (NSEs). A number of major observations with significant implications for child survival have been identified (Table 1).

Epidemiological studies have consistently found differential effects of live and non-live vaccines on overall mortality. Live vaccines have beneficial NSEs. Non-live vaccines may increase mortality, particularly for females, in spite of their pathogen-specific disease-protective effects. Many studies have focused on Bacillus Calmette-Guérin (BCG), where BCG has been shown to have beneficial NSEs in both animal and human challenge studies. Notably, different strains of BCG have different NSEs.

A growing number of studies have shown that vaccines may induce epigenetic changes, which can reprogram the innate immune system. Some vaccines will induce innate immune training, leading to an increased immune response to subsequent unrelated pathogens. Others may lead to innate immune tolerance, thereby rendering the recipient less likely to respond appropriately to subsequent unrelated challenges.

In February 2020, the 1st Optimmunize Conference was held at the Wellcome Genome Campus in Hinxton, near Cambridge, UK. The aim of the conference was to bring together epidemiologists, clinicians and immunologists to discuss and explore the underlying immunologic and genetic bases of NSEs, how generalizable they are, whether they can prove useful in geriatric and veterinary medicine, and why the NSEs often differ between sexes. This Special Issue provides a selection of the papers arising from the Conference….