STOPPING SCOURGES: Colored transmission electron micrographs of Zika virus (blue spheres, left) and Ebola virus (blue filaments and spheres, right)COMPOSITE IMAGE: ISTOCK.COM/LOLON, NIAID, CDC/CYNTHIA GOLDSMITHEbola. Zika. Two foreign words with instant name recognition. As the extremely contagious—and highly deadly—hemorrhagic fever caused by the Ebola virus was ravaging West Africa, the more insidious Zika virus was beginning to infect people in Brazil, causing many infants whose mothers contracted the virus during pregnancy to be born with severe neurological damage. Even though the Ebola epidemic has waned, cases are still being reported. And the onset of summer in the Northern Hemisphere has brought fears of a widespread mosquito-borne Zika epidemic to a fever pitch.
These two epidemics underscore the pressing need for vaccines and other therapeutics to protect against and treat infections with viruses such as Ebola and Zika, as well as a host of other pathogens, some of which are increasingly antibiotic- and drug-resistant. But developing a vaccine against an infectious agent—be it a bacterium, a virus, or a parasite—is not simple: the human immune response itself is complex, and the more genes an infectious agent has and the more readily it mutates, the more challenging it can be for researchers to develop an effective vaccine against the pathogen.
When a disease-causing microorganism enters the human body, it first elicits an innate immune response, followed by the proliferation and differentiation of B cells that produce circulating antibodies directed ...
