Scientists have found the chemical "glue" used by one type of pneumonia to attach itself inside the lungs, a discovery that brings research a step closer to a safe vaccine for "walking pneumonia" and possibly several other widespread diseases.

The researchers also have isolated a small quantity of an antibody that destroys the effect of the glue and that might be used as a vaccine if it could be made in quantity and administered safely.

Identifying the chemical, a protein through which "walking pneumonia" germs start their infection, is important because this disease is only one of many others that apparently act by the same sort of attachment mechanism as a first step in their infection.

They include gonorrhea, whooping cough, bacterial meningitis, diphtheria, and typhoid fever. Walking pneumonia is not usually fatal, but afflicts probably hundreds of thousands per year with weeks-long fever and cough.

The research team that found the attachment protein was led by Ping-chuan Hu of the University of North Carolina, who reports the finding in the April 16 issue of Science magazine. Several other research teams, including one at the National Institutes of Health, have helped the work on attachment mechanisms and disease progress.

The study reported success in stopping walking pneumonia, or Mycoplasma pneumoniae, in hamsters. It also reported finding that the bodies of humans suffering from the disease manufacture an antibody that attacks specifically the chemical glue that enables the pneumonia organism to attach itself. The disease takes hold when a person's body does not make enough antibodies.

Hu said the germ that causes walking pneumonia enters the lungs and attaches itself to the cell lining by means of a "finger" coated with the chemical glue called P-one protein. Only after attachment does it begin to produce substances that attack cells.

If researchers could produce an antibody that would search out and neutralize the P-one protein, the disease organism would then be quickly flushed out of the system by the natural cleaning action of the mucous membrane in the lungs.

Hu said that laboratory production of antibodies in vaccine quantity could take several years, but that it now seems possible.