184 PATENT

America as represented by the Secretary of the Arm,,,'

A living, attenuated, oral vaccine system is described for the immunization against enteric disease. This oral vaccine is a genetic hybrid derivative of an attenuated galactose epimerase- less strain of S. typhi which carries at least one protective antigen other than normal somatic S. typhi antigens. The oral vaccine can provide pro- tection against both typhoid fever and at least one other enteric disease. A bivalent oral vaccine is described wherein the non-typhoid protective antigen is the plasmid-encoded form I antigen of Shigella sonnei. A protective antigen from Shigella sonnei was transferred to a streptomy- cin resistant mutant ofS. typhi strain Ty21a. The transconjugant S. typhi strain expressed both S. typhi and S. sonnei antigens and protected ex- perimental animals against lethal infections with either S. typhi or S. sonnei. This strain is con- sidered to be useful as a vaccine against typhoid fever and bacillary dysentery caused by S. son- nei. The mutated galactose epimeraseless S. typhi strain such as S. typhi Ty21a strain can be utilized as a carrier strain for other protective antigens.

4632901

M E T H O D A N D A P P A R A T U S F O R I M M U N O A S S A Y S

Gunars Valkirs, Newton C Owen, Philip A Levinson assigned to Hybritech Incorporated

Disclosed herein is an apparatus and process for conducting immunoassays. The apparatus com- prises a first member which is a membrane or a filter to which is bound an antibody, typically a monoclonal antibody, or which is capable of extracting cells from a fluid sample. The ap- paratus further comprises a second member which is composed of absorbent material which acts when in contact with the first member to in- duce flow through the first member when a fluid sample is added to it. The apparatus is used to conduct immunoassays by applying a sample to the upper surface of the first member to bind antigen in the sample by means of antibody fixed to the first member or, in certain cases, by extra- cting cellular material which has antigen as- sociated with it. Addition of the sample is followed by addition of labeled antibody against the antigen being assayed followed by a washing step to remove unbound labeled antibody. The presence of labeled antibody on the first member after washing is indicative of the presence of the antigen in the sample being assayed.

ABSTRACTS

4632904

I M M O B I L I Z E D E N Z Y M E C O M P O S I T E S H A V I N G

C A R R I E R S D E R I V A T I Z E D W I T H AN O R G A N O T I T A N A T E

Siu-Leung Lee assigned to Ciba Corning Dia- gnostics Corp

The present invention relates to a novel im- mobilized enzyme composite. Suitable carriers such as controlled pore glasses or paper are coupled to various enzymes by derivatizing the carrier with an organotitanate. These com- posites are particularly suited for enzymatic reactions which prefer a non-aqueous, hydro- phobic environment.

4632909

M O N O C L O N A L A N T I B O D I E S W H I C H B L O C K I N F E C T I V I T Y O F

M A L A R I A L P A R A S I T E S T O M O S Q U I T O E S

Richard Carter, Louis Miller assigned to The United States of America as represented by the Department of Health and Human Services

Monoclonal antibodies have been developed that bind with one or more proteins located on the surface of gametes or zygotes of malaria parasites. These antibodies are specific for anti- gens on mosquito midgut stages of malaria para- site and sterilize the parasites in mosquitoes otherwise capable of transmitting the disease. The monoclonal antibodies are specific for the 255, 59 and 53 kilodalton surface proteins on Plasmodium falciparum and for the 25 kilodal- ton surface protein on zygotes and ookinetes of Plasmodium gallinaceum.

4634586

R E A G E N T A N D M E T H O D F O R R A D I O I M A G I N G L E U K O C Y T E S

David A Goodwin, Claude F Meares assigned to The Board of Trustees of the Leland Stanford Junior University

Leukocytes are radioimmunoimaged by in- jecting patients with an immunoreactive non- leukocidal conjugate of an anti-leukocyte antibody and a gamma-emitting radioactive metal chelate, waiting for the conjugate to localize on the leukocytes, injecting the patient with an antibody to the conjugate to clear the blood of background nonlocalized conjugate. and visualizing the leukocytes by scintillation scanning.