SI
SI
discoversearch

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor.  We ask that you disable ad blocking while on Silicon Investor in the best interests of our community.  If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.
Biotech / Medical : Biotech Valuation -- Ignore unavailable to you. Want to Upgrade?


To: Pseudo Biologist who wrote (235)6/17/1999 1:47:00 AM
From: scaram(o)uche  Respond to of 52153
 
The anti-flagellar? Unfortunately, flagellar antigens that elicit protective antibodies are about as variable, bug-to-bug, as are LPS-determined O-side chain determinants. That is particularly true for Proteus.

It's a useless curiosity.

- g -

Worse, the U.S. patent issued with just one lousy claim relating to serotype-specific MAbs for Proteus. The European and Japanese patents issued with all claims intact, however, and one could actually cover Pseudomonas with a few MAbs. The claims cover flagellar antigens for any microorganism, in the event that you have a parasite in mind.

No, the CNTO and XOMA MAbs failed, IMO, because they had absolutely zip to do with endotoxin or Gram-negatives. The concept was that MAbs could be raised that react with the invariant core (or "KDO") region of the LPS molecule. Never seen one that has passed my filter. There may be some that are "real", but E5 and HA-1A aren't among them, IMO. There actually is a MAb that recognizes a core determinant that is shared by all [tested] Pseudomonas isolates.... it's a no BS antibody, good affinity in a variety of physiologically relevant buffers and fluids. It's the one that I went to Cambridge to talk to Greg Winter about. Last I knew he was planning to humanize it, but I never heard anything more about it. When I found out about the "B cell" patent that GNE had licensed, I assumed that they had switched the anti-Pseudomonas MAb for the CD5 reagent, H65 (CD5 is found at low density on at least a subpopulation of B cells). I didn't know about the independent work from Santa Monica (Ingene?), until you told me about it just recently.

The Proteus MAb is a kick. It's not opsonizing, and it works great for certain injury models. However, it doesn't do squat if bug challenge is I.P. More fun?...... if you impregnate agar with the MAb and then stab with Proteus, the colony grows straight up into the air off of the plate instead of swarming.

It just immobilizes the suckers until, presumably, phagocytes come in and gobble. Put the bugs i.p., where flagella are not a big pathogenesis factor, and you have a lethal infection just as though you had administered saline.

It was a real shock.... my background was the polymorphism of the MHC, and I inherited "MAbs" made by M.D.s that had never touched a multiwell plate. Sad days for biotech.

Moreover, we (at Bayer/Cutter) had licensed HA-1A from Stanford before CNTO ever knew that it existed. Between the serology in my labs and the sensitive tests that Mike Collins had established, we declared it no better than saline and returned it. As you know, it later became a focus of intense patent litigation. The CNTO trials were later halted when it was determined that HA-1A recipients were dying more frequently than placebo controls.



To: Pseudo Biologist who wrote (235)6/17/1999 9:57:00 AM
From: scaram(o)uche  Read Replies (1) | Respond to of 52153
 
Look at Pfizer scramble (ABSC and now NRGN in the last two days, late to the party big-time). These guys are capable of insight when the match that's shoved into the sole of their shoe is down to a silly millimeter..... money to burn, they waited until it's going to hurt.

Deja goo...... Glaxo all over again. No brains, which is also reflected in the --IMO-- arbitrary and frivolous (I hope the punishment fits the crime and that the court is capable of severe injury) lawsuit against SIBI.

Again, can anyone point me to that prior art? If it exists, no problem..... I'll cut back on my investment and move to another lever.