Tomorrow's Federal Register will invite "pharmaceuticalor biotechnology companies" to enter into cooperativeresearch and development agreements (CRADA) withNational Institutes of Health (NIH) organizationsdeveloping a new class of non-steroidal, anti-inflammatorycompounds, appropriately called "antiflammins" by itsinventor.NIH's National Eye Institute (NEI) is already invitingpeople with a chronic eye inflammation, anterior uveitis, toenroll in the first human trial of antiflammins. Seven havesigned on so far.Janine Smith, a senior staff fellow at NEI's Laboratory ofImmunology, told BioWorld Today that corticosteroid eye-drops, the current treatment for acute iridocyclitis, as thepresumably autoimmune ocular affliction is also known,have unacceptable side-effects."Taking such medication repeatedly," she said, "can leadwithin five years to cataracts and glaucoma." As mostpatients are young, Smith noted, these penalties for steroiduse make it critical to develop non-steroidal substitutes.Antiflammins fill this bill, as confirmed by controlledpreclinical trials in rats. Animals were given experimentaluveitis by footpad injection of Salmonella typhimuriumendotoxin, which inflames the eyes. Then one eye receiveddrops of dexamethasone, a synthetic hydrocortisone; theother got an antiflammin instillation.Aqueous humor from the eyeballs of untreated control ratsinjected with endotoxin had 3,000 to 7,000 inflammatorycells per microliter of humor. Animals treated with one eyeeach of steroid or antiflammin showed 50 percent lessinflammation. In other words, as the NEI immunolgy lab'sdirector, Chi-Chao Chan, concluded: "Antiflammins are aseffective as corticosteroids in their ability to suppressendotoxin-induced uveitis."Chan belongs to a three-institute antiflammin collaborativegroup, led by the peptides' inventor, Anil Muhkerjee of theNational Institute of Child Health and Human Development(NICHHD), and dermatologist John diGiovanna, NationalInstitute of Arthritis and Muscoloskeletal and SkinDiseases (NIAMSD).diGiovanna is pursuing the potential of antiflammins astherapy for psoriasis, a hyperproliferative inflammatoryskin disease. It too is currently treated mainly bycorticosteroids.Muhkerjee, a geneticist and physician, isolated theantiflammin oligopeptides in the 1980s, and received U.S.Patent No. 5,266,562 protecting them on Nov. 30, 1993. Hechairs the developmental genetics section at the HumanGenetics Branch of NICHHD.As he explained to BioWorld Today, the antiflammins are anine-amino-acid segment of a protein he named"uteroglobin," by which a pregnant mother protects herunborn child _ immunologically, a foreign body _ fromrejection.This local maternal protein, Muhkerjee discovered, isinduced by progesterone, a steroid-precursor hormone thatmaintains pregnancy. That protein turned out to inhibit akey enzyme, phospholipase 2, (PLA2) which causes therelease of pro-inflammatory icosanoids. These in turnunleash battalions of inflammatory proteins involved in animmune response."If the mother's immune system," Muhkerjee said,"attacked the paternal antigens on the fetus, then it couldproduce all these inflammatory factors." To prevent thisself-defeating counterattack, uteroglobin inactivates PLA2,and prevents the inflammatory cascade."Uteroglobin," its discoverer added, "is a misnomer. It'salso produced in the lung, prostate, thymus and many otherorgans." It acts, he suggests, as a shield or modulator of theimmune system's immediate inflammatory response. "Sothis protein is present in almost all epithelia that areexposed to the external environment, such as thegastrointestinal, genitourinary and respiratory tracts."At uteroglobin's molecular level, he determined that theactive site of PLA2 inhibition was a nine-amino-acidsegment _ the antiflammins _ existing in two variantversions, with better than 50 percent homology. He foundthat antiflammins by themselves "profoundly inhibited"inflammation in animal models.Researchers who now work with these peptides must buythem from one of two manufacturers, Peptide Technologiesin Rockville, Md., or Bachem California, Panorama City,Calif. The latter's national sales director, Bruce Perry, toldBioWorld Today that his firm makes lyophilizedantiflammins "upon demand," by solid-state synthesis, "oneamino acid after another." Muhkerjee pays Bachem"something like $110 a mg."His lab clones and expresses human recombinantuteroglobin in Escherichia coli "in large quantity" forresearch.Work on this recombinant protein, in collaboration with agroup at George Washington University, showed that "inprostatic tumors, which are driven by testosterone andhighly invasive, the tumor cells could be made to stopinvasion if treated with the protein."A paper Muhkerjee submitted to Nature last week "adds adifferent dimension to uteroglobin. It shows that there is areceptor for it in various cell types. So now it seems that itnot only catalytically inhibits phospholipase A2 activity, italso has a receptor-mediated pathway, which may berelated to some of these tumor-cell metastases.To which Muhkerjee added: "We are trying to clone thereceptor. We have done site-directed mutagenesis in thatregion, but we do not yet know which region of this proteinis involved in interacting with the receptor."And that's where our lab is at now."Where would Muhkerjee welcome collaboration withindustry, as per tomorrow's Federal Registerannouncement?"Some of our work involves a little more involvement, andthere we need some help," he replied. "Somebodyproviding the peptides for the protein. Somebody providingthe manpower to test these. We have one primate model onwhich we have done preliminary work on neonatalrespiratory distress syndrome (NRDS)."Premature infants, he explained, are born before their lungshave enough surfactant to make breathing possible. "Incurrent therapy," he said, "you give such a baby a puff ofartificial surfactant so it begins to breathe."But because of this treatment," he observed, "a third of theneonates end up as chronic lungers, eight or 10 years later,with life-threatening chronic bronchial dysplasia."Because uteroglobin is also produced in the lung, but notenough in preemies, he and a group at the University ofTexas in San Antonio are instilling the recombinant proteininto the lungs of baby monkeys by endotrachealaerosolization, "and we have shown that there is actuallysome improvement."He wants to get "a larger number of animals to produce adose-response curve, giving increasing amounts of protein,test whether fetal uteroglobin is endogenously present, andsee in a long-term way if it prevents bronchopulmonarydysplasia or not."Muhkerjee concludes: "This is one of my pet projects. Iwould like to see if it works out. So I would very muchwelcome industrial collaboration."[Editor's Note: For licensing and/or CRADA informationconcerning NIH's antiflammin patent portfolio, and theircommercial development, contact contract specialist CarolLavrich at (301) 496-7735, extension 287. CRADAproposals must be received 90 days from Aug. 16, theirFederal Register publication date No such deadline appliesto licensing agreements.] n
-- David N. Leff Science Editor
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