Subject: Single-Shot Vaccine for Immunization Against Several Diseases Moves Closer 
Date: Published: 6/6/91 (84 lines)
Source: Wall Street Journal. Copyright Dow Jones & Co. Inc.

    Technology:
    Single-Shot Vaccine for Immunization
    Against Several Diseases Moves Closer
    ----
    By Jerry E. Bishop
    Staff Reporter of The Wall Street Journal

    Scientists took a key step toward a vaccine that someday
 might immunize a person against a dozen or more viral and
 bacterial diseases with a single injection.
    Two teams of U. S. researchers reported they had
 successfully engineered "foreign" genes from viruses and
 bacteria into a bacterium, known as the BCG microbe, that
 already is widely used as a vaccine against tuberculosis.
 When the genetically engineered BCG organism was used as a
 vaccine in mice, the rodents showed signs of developing
 full-scale immunity against the viruses and bacteria.
    Present vaccines each immunize only against a single
 disease, although most children receive a combination of four
 vaccines in a single shot against diphtheria, pertussis,
 tetanus and polio.
    The experiments, reported in this week's issue of the
 scientific journal Nature, suggest it may be possible to use
 the genetically engineered BCG microbe as a one-shot vaccine
 that could immunize a person against several diseases
 simultaneously, including tetanus, diptheria, hepatitis, Lyme
 disease, measles and malaria.  The technique might also be
 used as a vaccine against acquired immunodeficiency syndrome,
 or AIDS.  
    The immediate beneficiary of the experiments, however, is
 a Gaithersburg, Md., biotechnology company, MedImmune Inc. In
 May, MedImmune raised $24.7 million in a public offering that
 attracted investors partly because of the company's research
 on the "multivalent" vaccine made with the genetically
 engineered BCG microbe.
    MedImmune obtained rights to the BCG-based vaccine
 technology from three academic institutions, the Whitehead
 Institute at Massachusetts Institute of Technology in
 Cambridge, Mass., the Albert Einstein College of Medicine in
 New York and Stanford University in Stanford, Calif.
    MedImmune's research in using the BCG microbe for a
 vaccine against the virus that causes AIDS is being funded by
 Merck & Co. while work on a BCG-type vaccine against Lyme
 disease and hepatitis B is being funded by Connaught
 Laboratories Inc., Swiftwater, Pa.
    In their newly published reports, two scientific teams
 note that the BCG microbe is ideal for a vaccine.  In the past
 40 years it has been used as a tuberculosis vaccine in more
 than two billion people and is safe enough to be given to
 newborn infants.  BCG stands for bacille Calmette-Guerin,
 named after the two French scientists who developed the
 tuberculosis bacillus, or bacterium, as a vaccine.
    The trick pulled off by both teams of U. S. scientists was
 to get various foreign genes inserted into the BCG bacterium.
 They also had to ensure that the inserted genes would produce
 their "foreign" proteins in the BCG bacterium in a way that
 the proteins would be exposed to the immune system of the
 mice (or humans) so that an immunity could be built up.
    Genes taken from the AIDS virus and from the microbe that
 causes tetanus, or "lockjaw," as well as a gene for a common
 enzyme were successfully inserted into the BCG bacterium by a
 team from Albert Einstein College, the University of
 Pittsburgh and MedImmune.  They added that they also had
 inserted genes from 17 other viral, bacterial and parasitic
 microbes into BCG but didn't give details.  A team from the
 Whitehead Institute reported they had successfully inserted
 three genes from the AIDS virus into BCG. 
    Both teams said mice vaccinated with the genetically
 engineered BCG developed a surprising across-the-board
 immunity to the proteins produced by the inserted genes.  The
 mice developed antibodies to the proteins, as is common with
 vaccines against viruses.  But the mice also developed white
 blood cells, called T lymphocytes, that are capable of
 attacking and destroying foreign cells such as bacteria.  The
 animals also began producing such substances as interferon,
 which the body uses to ward off infections.

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