PATENT ABSTRACTS 139

x O--R~

HO J CH3~ ~ 0 1 0 -~

y CH3 CH~-O H

c.- _ o t ; ' J O ~ N ~ c H 3

Y

Novel demethylmaytansinoids representable by the formula: (wherein X is CI or H; RI is H or acyl group) are produced from may- tansinoids by means of enzymic transforma- tion. The demethylmaytansinoids are useful as antifungal, antiprotozoal or antitumor agents.

4361647

SANDWICH IMMUNOASSAY AND COMPOSITIONS FOR USE THEREIN

Jack Remington, Fausto Araujo, assigned to Palo Alto Medical Research Foundation

An improved sandwich immunoassay for Toxoplasma gondii antigens associated with acute forms of Toxoplasma infection is dis- closed. The assay employs either an F(ab')2 fragment of lgG which reacts specifically with such antigens or a monoclonal anti- body for such antigens as the substrate layer in the sandwich. The assay is sensitive and, unlike prior sandwich assays for the antigen, is not affected significantly by cross-reactions with rheumatoid factor.

4361574

INHIBITORS OF MAMMALIAN COLLAGENASE

Norman Grant, Donald Clark, assigned to American Home Products Corporation

o N ~ ~ H D , , C O 2 R

N

R I

A method of inhibiting mammalian col- lagenase by using e-(p-substituted phenyl)- t hiazolo(3,2-a) benzimidazole-2.alkanoic acids and esters thereof, and the pharma- ceutically acceptable salts thereof.

4361550

COMPLEMENT-FIXING MONOCLONAL ANTIBODY TO

HUMAN SUPPRESSOR T CELLS AND METHODS OF PREPARING SAME

Patrick C. Kung, Gideon Goldstein, assigned to Ortho Pharmaceutical Corporation

Hybrid cell line for production of mono- clonal antibody to an antigen found on normal human suppressor T ceils. The hybrid is formed by fusing splenocytes from immunized CAF1 mice with P3X63Ag8UI myeloma cells. Diagnostic and therapeutic uses of the monoclonal antibody are also disclosed.

~ 6 1 ~ 9

COMPLEMENT-FIXING MONOCLONAL ANTIBODY TO HUMAN T CELLS, AND

METHODS OF PREPARING SAME

Patrick C. Kung, Gideon Goldstein, assigned to Ortho Pharmaceutical Corporation