although antitoxins and antivenins have been developed and used for years , it is important that any immune globulins for prevention or treatment of reactions due to bee stings be safe and effective , meeting current standards for sterility , pyrogenicity , residual moisture , and general safety , to avoid severe reactions that may be caused by the immune globulins themselves . in the method for manufacturing immune globulins according to the present invention , a pool of virucide - treated donor plasma is first assembled , typically from donors who already have hyper immune serum globulin . an aliquot pool of the plasma units is made typically to equal about 10 ml , prior to pooling , based on the original volumes or weights of the plasma bags . it is then necessary to determine the total igg of the aliquot pool , the total igg4 of the aliquot pool , the total antibody in the aliquot pool , and the proportion or percentage of blocking antibody in the igg4 fraction in the aliquot pool . the determination of the total igg of the aliquot pool is preferably performed by a sensitive technique for detecting and measuring antibodies in a solution , such as an enzyme - linked immunosorbent assay ( elisa ) method , and / or radial immune diffusion ( rid ) method , whichever give the most reproducible and accurate data against known standards . the total igg4 of the aliquot pool can also be determined similarly by elisa or rid methods . the total antibody can similarly by determined either by elisa , or a radioimmunoassay ( ria ) or rast tests , providing the latter can be standardized for true quantitative determinations of specific antibodies . it is important to obtain the most accurate and sensitive assay of the proportion or percentage of the anti - venom in the igg4 fraction . the best method is an elisa technique that reacts with bee - venom specific antibody of the plasma pool . this technique requires comparison with an anti - total igg . an acceptable alternative is the determination of the ratio of diffusion of the igg and igg4 in rid plates . the purpose of this analysis is to compare the final igg4 preparation in order to estimate losses and costs of production . these tests are required because igg4 offers a unique ability to provide blocking antibody with known freedom from any ability of the antibody to bind to mast cells and basophiles , unlike igg 1 , igg2 and igg3 , which have low affinity receptors for these important allergy mediator cells . pure igg4 blocking antibody has not been used before for this purpose . later in the method , the same series of tests are required on the fractionated globulin , first as a confirmation of the tests performed on the donor plasma , but also to estimate the dosage and vialing requirements and to estimate the costs of manufacturing . other tests on the globulin preparations are really standard good manufacturing practices ( gmp ). these in summary are : a ) acute toxicology in two rodents ; b ) pyrogen tests by the limulus method ; c ) sterility tests after sterile filtration and before vialing and lyophilization ; d ) total protein by kjeldahl or other suitable methods ; e ) protein electrophoresis ; f ) total purity analysis for any contaminating proteins or other impurities ; g ) gel filtration for determination of split products or polymers ; h ) analysis for viral contaminants , e . g . hiv , hbv , hcv etc . by the most sensitive methods , extant ; and i ) other tests required by the fda and in the federal register . following testing of the donor plasma pool , the donor plasma pool is typically frozen for storage until it is time for further processing of the donor plasma pool . the plasma units selected from prior antibody analysis ( usually 600 to 800 milliliters each ), that are to constitute the final plasma pool to be fractionated , are removed from the freezer and allowed to thaw at approximately 5 ° c . for 48 – 72 hours . the plasma units are then pooled into a sterile container under aseptic conditions in a class 100 or less clean room or laboratory air - flow containment area . the weight of the plasma pool is then measured to obtain the total volume . the plasma should be treated in accordance with a virucidal method , such as the “ solvent - detergent ” method of the new york blood bank or by careful heating to 60 ° c . whatever method is used to sterilize the plasma pool , the plasma should be treated to make it comparable to the original plasma in terms of its suitability for fractionation by the method to be described . for example , it is necessary that the final post - sterilized pool have the same ph and ionic strength ( as judged by conductivity measurements ) as the original pre - sterilized pool of plasma . the sterilized plasma pool is then treated by adding approximately 7 grams of microcrystalline silica ( aerosil 200 ) per liter of the pool . the aerosil is previously sterilized at about 180 °– 185 ° c . for at least 4 hours in a hot air oven . the addition of the aerosil to the plasma should be done aseptically . the plasma should then be stirred slowly ( so as not to create foaming ) for about 1 hour at room temperature under aseptic conditions . the suspension is then centrifuged at about 3000 × g for about 30 minutes at 2 – 8 ° c . degrees centigrade . the supernate is carefully decanted into a large sterile and depyrogenated container . the aerosil pellet is then resuspended in a volume , equivalent to 14 % of the starting volume of the plasma , of pyrogen - free 0 . 9 % sodium chloride solution . after mixing , the suspension is centrifuged at about 3000 g for 30 minutes at 2 – 8 ° c ., maintaining sterility throughout the procedure . the supernates are then combined and the plasma pool is clarified by passage of the plasma pool through a sterile millipore aw 19 pre - filter , or equivalent membrane . the conductivity of a small sample of the filtered pool should then be determined and the bulk solution diluted with sterile pyrogen - free distilled water to reach a conductivity of 3 . 5 to 6 . 0 millisiemens , after the addition of n / 10 hcl to bring the ph to 6 . 5 . the fractionation method described requires the passage of the plasma through anionic and cationic resin beds . it is recognized that there are several alternative choices that can accomplish the aim of separating in pure form clinically effective igg4 . the method described in detail that follows is the presently preferred one . the diluted plasma is passed through a suitable size bed ( 16 – 50 l ) of deae - sepharose ( cl - 6b ) which has been equilibrated with 0 . 025 m sodium phosphate at ph 6 . 5 . the material is pumped through the bed at the rate of about 175 ml / minute . the plasma should then be followed with 0 . 025m sodium phosphate ph 6 . 5 . the ph 6 . 5 buffer solution contains 0 . 653 gm na 2 hpo 4 . h 2 o and 2 . 855 gm of nah 2 po 4 . h 2 o per liter of distilled water ( pyrogen free ) at 25 ° c . the effluent is preferably monitored at 280 nm with a suitable instrument , such as the pharmacia single path monitor uv - 1 . the effluent can be collected when the uv trace on the recorder indicates a sharp rise in absorbency , and collection is continued until the absorbency drops to about 5 % of the peak value . the effluent is maintained at ph 6 . 5 , and is passed directly through a similarly prepared , but about one third the column volume , of cm - sepharose ( cl6b ) equilibrated to ph 6 . 5 with 0 . 025 m sodium phosphate buffer as above . the material is pumped through the column as before , at about 175 ml / minute . the protein solution should then be followed with 0 . 025 m sodium phosphate at ph 6 . 5 . the effluent is then monitored as before at 280 nm with a suitable instrument , and the effluent should begin to be collected when the uv trace on the recorder indicates a sharp rise in absorbency . collection should be continued until the absorbency drops to about 5 % of the peak value . this effluent is mostly , if not entirely , igg4 . the resin beds as well as the buffer solutions and collecting vessels should be pyrogen - free and sterilized by autoclaving . sodium chloride ( sterilized and pyrogen - free ) is then added to a final level of 0 . 03 to 0 . 05m , and the effluent immune globulin is concentrated , preferably by ultrafiltration with a suitable apparatus , such as the millipore cassette system with a 10 , 000 nominal molecular weight cut - off membrane ( ptgc 000 05 ca no ). the filtration rate is about 425 ml / minute and the approximate inlet and outlet pressures are 16 psi and 10 psi respectively . when the starting volume has been reduced about 70 - fold , the cassette is flushed with about 300 – 500 ml of 0 . 05m sodium chloride solution , and this is added to the immune globulin concentrate . the solution is then frozen and maintained at − 30 ° c . or lower . the solution is then thawed , and sufficient sterile and pyrogen - free lactose is added to the bulk solution to result in a solution of about 0 . 25 to 0 . 35 osmolar . the concentrated immune globulin is then sterile filtered through a 0 . 22 micron membrane filter , and stored at about − 11 ° c . or colder until vialing and lyophilization . the sample is then thawed at about 5 ° c ., and filtered through a 0 . 22 micron filter . samples are removed for tests of sterility , pyrogenicity and potency . following successful testing , the vials are filled aseptically at a specified fill volume of bulk solution . the vials are subjected to a standard freeze - dry cycle , and the chamber is restored to atmospheric pressure with sterile nitrogen . the freeze - drying cycle is dependent on the apparatus used or the vendor used if this work is sub - contracted . samples are obtained for moisture determination during drying of the product at full vacuum at the terminal drying temperature . after acceptable moisture results have been obtained , the chamber should be restored to atmospheric pressure with sterile nitrogen . within the lyophilizer , the freeze - dried vials should be aseptically stopped and sealed . the results of these methods is the production of an immune globulin of high effectiveness and safety for the treatment of a wide range of type i allergies while maintaining current standards for sterility and pyrogenicity . it will be apparent from the foregoing that while particular forms of the invention have been illustrated and described , various modifications can be made without departing from the spirit and scope of the invention . accordingly , it is not intended that the invention be limited , except as by the appended claims .
a method of manufacturing hymenoptera - immune globulin is disclosed . in a presently preferred embodiment , the method involves the steps of concentrating a raw immune globulin solution ; freezing the concentrated immune globulin solution ; thawing the frozen concentrated immune globulin solution ; adding sufficient mono or disaccharide to the thawed concentrated immune globulin solution to yield a solution of about 0 . 25 to about 0 . 35 osmolar ; filtering the thawed concentrated immune globulin solution ; and lyophilizing the concentrated immune globulin solution .