Abstract:
The present invention concerns a device for improved hygienic monitoring of individually ventilated caging (IVC) rack systems for laboratory animals and method for contamination-free removal of biological samples from unwanted organisms from the IVC-rack system. The device allows the performance of sampling operations on a ventilated shelving system in a safe and effective manner, without interfering with the ventilation air flow. The method of the invention allows the removal and transfer of the biological sample from inside the IVC-rack in a contamination-free manner by enabling a safe transfer of the sample from inside the IVC-rack system to any further processing procedure for analysis of the biological sample outside the IVC-rack system. It is also an object of the present invention to provide a device which is adapted to be used also on existing ventilated shelving systems, allowing the refitting of existing IVC-rack systems.

Description:
[0001]    This application claims the benefit of Italian Patent Application Serial No. 102015000067602 filed Oct. 30, 2015, which is hereby incorporated by reference in its entirety. 
       FIELD 
       [0002]    The present invention relates to a device for improved monitoring of the hygienic conditions in IVC (individually ventilated caging) rack systems for laboratory animals, a method for contamination-free removal of biological samples, particularly of unwanted organisms from the IVC rack system for laboratory animals containment cages, and a sampling method for sampling airborne particles in a ventilated shelving storage in order to analyze potential infections of the animals in the IVC rack system. 
       BACKGROUND 
       [0003]    The present invention belongs to the field of hygienic monitoring of animal containment facilities, particularly IVC (individually ventilated cages) rack systems. 
         [0004]    Ventilated shelving storage units are currently known and used for housing laboratory animals, said units enabling a plurality of cages containing animals to be arranged in a tidy manner. 
         [0005]    It is also well-known, among those skilled in the art, that the shelving storage units of the kind mentioned above also cater for the need to ensure air circulation inside the cages containing the animals, and prevent said air from being released into the atmosphere. 
         [0006]    For this purpose, the cages for containing the animals according to the prior art are equipped with at least two valves, one for delivering and one for discharging the air, while the shelving storage unit or rack system comprises at least one line, or plenum for delivering clean air into the containment cages and one line, or plenum for conveying (removing) the foul air away from the cages. 
         [0007]    It is moreover well known that particular care must be taken for the purpose of treating the foul air leaving the cage, because same could be contaminated by pathogens contained in the cages. Moreover, the foul air coming from the cages often contains solid substances in the form of airborne particles and/or micro-particles arising from the solid substances and/or from the dust generally existing in the cages. 
         [0008]    Still a further issue relates to the fact that the air to be delivered to the cages must be filtered in advance to comply with the required quality standards so as to ensure that the animals are always kept in an environment with controlled characteristics. For this purpose, the cage rack systems are generally fitted with an air circulation system that delivers air to the clean air plenum only after it has been pre-filtered and usually treated with a HEPA (high efficiency particulate air) filter, which is capable of retaining any airborne particles. 
         [0009]    However, the use of IVC rack systems in laboratory animal husbandry has posed new challenges relating in particular to effective microbiological monitoring. Generally speaking, monitoring microbiological conditions (in the following “microbiological monitoring” for the sake of conciseness), in particular of SPF (Specific Pathogen Free) animals, is based on international standards, which have been established by scientific societies in the international laboratory science community. 
         [0010]    As an example, in Europe and in the United States microbiological monitoring standards are established by the FELASA (Federation of European Laboratory Animals Science Association) and by the ACLAM (American College of Laboratory Animal Medicine), respectively. As it is known, it is very important to prevent entry into the cages and spread among the cages of unwanted infectious agents, such as for example bacteria and viruses, and therefore the use of individually ventilated cage (IVC) rack systems in laboratory animal husbandry has dramatically increased in the last years. In fact, IVCs not only allow for a control of environmental conditions such as humidity and temperature, they also allow to provide each cage with filtered air, which protects the animals in the cages from airborne infectious or other noxious particulate agents present in the environment. 
         [0011]    Microbiological monitoring of animals requires a regular analysis for the presence of infectious agents which may be particle-associated or air-borne. In fact, although housing of animals in IVC rack systems reduces the risk of infection from the environment, routine handling operations such as, for example, changing of bedding and experimental handling of animals, (usually carried out in changing stations such as laminar flow hoods or the like), or even in an unprotected environment, still harbors a risk of exposing the animals to environmental conditions and infectious agents and, thus, to infections. 
       STATE OF THE ART 
       [0012]    As stated here above, in the field of cages for animals, an increasing need is felt to monitoring the microbiological conditions of the cages. 
         [0013]    In this respect, it has to be noted that each individual cage represents its own zone of bio-containment, so that traditional monitoring methods such as exposure of sentinels to airborne infectious agents present in the room air are inappropriate. In the same way, sampling of random animals from the IVC rack is usually not suitable, as in this case the use of large numbers of potentially valuable animals is required. 
         [0014]    Thus, in an attempt to overcome the above mentioned drawbacks, the use of sentinels exposed to soiled bedding has been developed. However, soiled bedding may not detect pathogens not transmitted by the faecal-oral route. 
         [0015]    Pathogens can comprise viruses, fungi, bacteria, spores, parasites and similar. 
         [0016]    As a further development of traditional methods of microbiological monitoring, the used of sentinels exposed to exhaust air from the entire rack has been suggested. As an example, according to prior art document DE 100 26 208, detection of pathogens is carried out by delivering to at least one cage of sentinel animals samples of the exhaust air coming from the rack. Therefore, the sentinel animals serve as bio-indicators for the detection of air-borne infectious agents which may be present in the air either due to the development of a disease or indirectly due to to the development of antibodies or amplification of pathogens, which may be detected according to either immunological or microbiological methods. 
         [0017]    The sentinel-based monitoring system described in DE 100 26 208 is affected by several shortcomings. As a first drawbacks, the sentinel animals have to be sensitive and susceptible to the respective pathogens in order to develop an immune response or disease. In addition, a minimum infectious dose of the respective pathogen has to be present and there may, furthermore, be a substantial time lag for the sentinels to develop a disease, amplify the pathogen and/or develop antibodies. Thus, by the time a pathogen is detected, a large number of affected animals may have been infected and subsequently used in experiments, thus rendering the results as obtained questionable and/or less reliable. 
         [0018]    As a further drawbacks, for the purpose of efficiently monitoring different racks at different times a large number of sentinel animals is required. However, to sacrifice a large number of animals merely for health monitoring purposes does not only constitute an enormous financial burden, but represents a less-desirable practice for ethical and animal-welfare reasons. 
         [0019]    The international patent application WO2009115220 in the name of the same Applicant discloses a cage rack system and method for sampling airborne particles from a cage rack system suitable to accommodate a plurality of cages, ventilated either individually or in groups, said system being provided with air guidance means for delivering air to the air-inlet and/or collecting air from the air-outlet through integral (common) or separated conduits, wherein at least one sampling unit for collecting airborne particles from the air is further provided. 
         [0020]    According to this method, the sampling unit is adapted to collect the airborne particles by means of a cyclonic flow path configured to cause a separation of the particles from the air. 
         [0021]    The disclosed sampling unit comprises one or more components, and can be arranged for analyzing, evaluating, investigating, controlling and/or monitoring the incoming air and/or the outgoing air. 
         [0022]    The incoming air can be checked in order to have a basis for comparing the respective results with the results from one or more components of the air guidance system analyzing, evaluating, controlling and/or checking the outgoing air. In case one or more animals are infected with pathogens, these pathogens are delivered to the air either by the air exhaled from the animals or by excretions of the animals or even by any other contamination of the air due to at least partially contaminating particles in the exhaust air. 
         [0023]    The sampling unit according to WO2009115220 can further comprise at least one cyclone and at least one collection vessel, said one or more vessels being disposed downstream of the cyclone. The cyclone can be established by a plurality, such as two or three, of stages in order to minimize its size and/or enhance its effectiveness. As an alternative or in addition, a plurality of cyclones connected in series or parallel with differently located ports can be connected to the air guidance system. 
         [0024]    According to a preferred embodiment disclosed in WO2009115220 the sampling unit can be replaceably attached to and/or inserted into a conduit of the air guidance system. 
         [0025]    The conduit can comprise a flange and/or access for the direct attachment or insertion of the sampling unit. The sampling unit can be attachable to and/or into the flange and/or access in an air tight manner, preferably by a snap fit, a coupling ring or a bayonet coupling. 
         [0026]    The possibility to detachably associate the sampling unit to a conduit of the air guidance system of the cage rack, is an aspect which is particularly aiming at a modular possibility to detect, analyze, evaluate, control and/or monitor the conditions of a certain cage or common group of cages according to the needs and/or circumstances, wherein said needs may change depending on the specific animals contained in the cages at any given point in time. 
         [0027]    The prior international patent application WO2009115220 therefore contemplates the possibility to provide an IVC rack system with a sampling unit, preferably detachably associable to a conduit of the air guidance system of the IVC apparatus, However, the present invention bears some major improvements with regard to the handling and transfer of the biological sample originating from the airflow of inside the IVC-rack system. 
         [0028]    An unsolved problem of the disclosed IVC rack system and the respective method for sampling airborne particles from a cage rack system according to WO2009115220 relates to the safety conditions under which samples are drawn from the airflow inside the IVC-system so as to avoid any contamination. In order to safely remove the sampling unit from the conduit system it seems to be mandatory that, during the opening operation the air-flow be stopped in order to avoid contamination both of the operator and the system outside and for the animals inside the IVC-rack system and the sample itself. 
         [0029]    Not least, a problem left unsolved by the system and method for sampling airborne particles from a cage shelving system according to the prior art is represented by the fact that it is not possible to provide already existing cage rack systems with the sampling unit, in a very easy and cost-effective manner. 
       SUMMARY 
       [0030]    The main aim of the present invention is therefore that of providing a device for improved hygienic monitoring in IVC-rack systems for laboratory animals and a method for contamination-free removal of biological samples of unwanted organisms from the IVC rack system in order to subsequently analyze potential contaminations from the inside of the IVC rack system. 
         [0031]    At the same time, according to the present invention, solutions are provided to overcome further drawbacks left unsolved by the prior art. 
         [0032]    It is also an object of the present invention that of providing a ventilated shelving storage system comprising said device according to the invention. 
         [0033]    It is a further object of the present invention to provide a device for improved hygienic monitoring in IVC-rack systems for laboratory animals which can be easily and safely handled by the operator without the need to interrupt the rack system ventilation. Likewise, the present invention shall allow the withdrawal of the sample from the air guidance system of the cage rack without disturbance of the existing regular air-flow. 
         [0034]    Not least, a further object of the present invention is that of providing a device which can be installed also on already existing cage rack systems, thus enabling the retrofitting of already existing apparatuses. 
         [0035]    It is a further object of the invention to enable improvement of hygienic monitoring of colonies of laboratory animals kept in individually ventilated cages. It has been shown that the data generated with the device according to the present invention provide much better information on the health status of the animal colonies. In comparison to the method according to the prior art comprising sentinel animals of the prior art, the data generated with the device and method of the present invention are more sensitive and available in less time. The device and method according to the present invention makes the use of extra animals for hygienic monitoring unnecessary. 
         [0036]    In view of the above, in particular in order to achieve both the above aims and further aims that will become more clear from the following detailed description of a preferred embodiment of the present invention as depicted in the drawings to be regarded as an illustrative and not limitative example of the present invention, disclosed in the present application is a device for contamination-free removal of biological samples from a ventilated shelving storage system for laboratory animals containment cages, comprising
       a support frame, and sampling means, in turn comprising a capturing scaffold and capturing means arranged within a capturing portion of said capturing scaffold.       
 
         [0038]    As further disclosed, said sampling means may be associated in a removable manner with the support frame. 
         [0039]    As further disclosed said support frame may comprise one or more seats for receiving one or more sampling means and at least one aperture adjacent to said one or more seats. 
         [0040]    Still as disclosed, said sampling means may comprise a sheath, a capturing scaffold associated to said sheath, and a capturing means associated to said capturing portion. 
         [0041]    As further disclosed, said capturing scaffold may be inserted into the sheath and be movable in a sliding manner with respect to the sheath to a capturing position located in the aperture, between a closed position in which said capturing portion containing the capturing means is completely inserted into the sheath and, an open position in which said capturing portion containing the capturing means is completely exposed to the air flow, comprising the area of the aperture not covered by the capturing portion and the flow passage area of the ventilated shelving storage system. 
         [0042]    Still as disclosed, one or more seats for receiving sampling means may be delimited by guiding means, so that each sampling means can be slidingly inserted into a dedicated seat. 
         [0043]    As further disclosed, said guiding means may comprise straight and elongated guides, each seat being delimited by a couple of straight and elongated guides. 
         [0044]    As disclosed, said support frame may comprise a substantially planar plate with a substantially rectangular profile comprising a first short edge, a second short edge, a first long edge and a second long edge connecting said short edges. 
         [0045]    As disclosed, said support frame may further comprise at least one flow passage area and/or said sheath and said capturing scaffold may are made of disposable material. 
         [0046]    Further disclosed is a ventilated shelving storage system for laboratory animals containment cages comprising a load-bearing structure for supporting a plurality of cages and an air guidance means comprising a filtering unit, said system comprising a device as disclosed above. 
         [0047]    As disclosed, the device may be associated in a removable manner to said filtering unit ( 305 ). 
         [0048]    Still as disclosed, said filtering unit may comprise a containment case and said support frame system of said sampling collection device may be configured to be inserted in a sliding manner into said containment case. 
         [0049]    According to the disclosure, said filtering unit comprise a pre-filter and said device is inserted into said filtering unit underneath said pre-filter. 
         [0050]    Further disclosed is a method for contamination-free removal of biological samples from a ventilated shelving storage system for laboratory animals containment cages by means of a device according to the above, the method comprising the following steps:
       providing a sampling means for said device,   positioning of the sampling means of said device from the closed position to the open position,   collecting of biological samples from unwanted organisms,   positioning of the sampling means of said device from the open position to the closed position,   pulling off the sampling means from the filtering unit,   transferring the sampling means to a ventilated hood,   shifting the capturing scaffold, comprising the capturing means to the open position,   transferring the capturing means to a reaction vessel for analysis of biological samples of unwanted organisms, preferably by PCR.       
 
         [0059]    Still in view of the above, according to an embodiment of the present invention there is provided a device for contamination-free removal of biological samples from a ventilated shelving storage system for laboratory animals containment cages, said device comprising—a support frame, and sampling means in turn comprising a capturing scaffold, and capturing means arranged within a capturing portion of said capturing scaffold, said sampling means comprising a sheath, said capturing scaffold being associated to said sheath, said capturing scaffold being inserted into the sheath and movable in a sliding manner with respect to the sheath to a capturing position located in an aperture, between a closed position in which said capturing portion (containing the capturing means) is completely inserted into the sheath, and an open position in which said capturing portion is completely exposed to the an air flow, comprising the area of the aperture not covered by the capturing portion and the flow passage area of the ventilated shelving storage system. 
         [0060]    According to an embodiment, said sampling means is associated in a removable manner with the support frame. 
         [0061]    According to an embodiment, said support frame comprises one or more seats for receiving one or more of said sampling means, said aperture being adjacent to said one or more seats. 
         [0062]    According to an embodiment, said one or more seats for receiving said sampling means are delimited by guiding means so that each sampling means can be slidingly inserted into a dedicated seat. 
         [0063]    According to an embodiment, said guiding means comprise straight and elongated guides, each seat being delimited by a couple of straight and elongated guides. 
         [0064]    According to an embodiment, said support frame comprises a substantially planar plate with a substantially rectangular profile comprising a first short edge, a second short edge, a first long edge and a second long edge connecting said short edges. 
         [0065]    According to an embodiment, said support frame further comprises at least one flow passage area. 
         [0066]    According to an embodiment, said sheath and said capturing scaffold are made of disposable material. 
         [0067]    According to the present invention there is further provided a ventilated shelving storage system for laboratory animals containment cages comprising a load-bearing structure for supporting a plurality of cages and an air guidance means comprising a filtering unit, said system comprising a device according to any one of the above embodiments. 
         [0068]    According to an embodiment, the device is associated in a removable manner to said filtering unit. 
         [0069]    According to an embodiment, said filtering unit comprises a containment case and said support frame system of said sampling collection device is configured to be inserted in a sliding manner into said containment case. 
         [0070]    According to an embodiment, said filtering unit comprises a pre-filter and said device is inserted into said filtering unit underneath said pre-filter. 
         [0071]    According to the present invention there is further provided a method for contamination-free removal of biological samples from a ventilated shelving storage system for laboratory animals containment cages by means of a device according to one of the above embodiments, said method comprising the following steps:
       providing a sampling means for said device,   positioning (moving) the sampling means of said device from the closed position to the open position,   collecting biological samples from unwanted organisms,   positioning (moving) the sampling means of said device from the open position to the closed position,   pulling off the sampling means from the filtering unit,   transferring the sampling means to a ventilated hood,   shifting the capturing scaffold, comprising the capturing means to the open position,   transferring the capturing means to a reaction vessel for analysis of biological samples of unwanted organisms, preferably by PCR.       
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0080]    Further characteristics and advantages of the present invention will become clear from the following detailed description of the embodiments of the present invention depicted in the drawings; however, the present invention is not limited to the embodiments disclosed in the following and depicted in the drawings but comprises all equivalents thereof which may be obvious to those skilled in the art in view of the following disclosure. 
           [0081]    In the drawings: 
           [0082]      FIG. 1  shows an example of ventilated cage rack or shelving system; 
           [0083]      FIG. 1 a    shows a scheme of the air filtering unit of the ventilated cage shelving system of  FIG. 1 ; 
           [0084]      FIG. 2  shows the device according to the present invention partially inserted in the filtering unit of the air guidance means of the shelving system; 
           [0085]      FIG. 2 a    shows a schematic representation of a support frame as part of the device according to the present invention. 
           [0086]      FIG. 2 b    shows a schematic representation of two alternative embodiments of the sampling means of the device according to the present invention, in particular having respectively a flat and a cylindrical configuration; 
           [0087]      FIG. 2 c    shows a schematic representation of a device according to the present invention comprising the support frame and the sampling means reversibly connected to each other; 
           [0088]      FIG. 3  is a bottom view of the support frame which is part of the device according to the present invention; 
           [0089]      FIG. 4  shows a perspective bottom view of the support frame of  FIG. 3 ; 
           [0090]      FIG. 5  shows a plant view of the sampling means which are part of the device according to the present invention; 
           [0091]      FIG. 6  shows a perspective view of the sampling means of  FIG. 5 ; 
           [0092]      FIG. 7  shows a top view of the device according to the present invention, comprising the support frame and two sampling means inserted therein; 
           [0093]      FIG. 8  shows the same view of  FIG. 7  in which one of the two sampling means is partially extracted from the support frame; 
           [0094]      FIG. 9  represents the bottom view of the device of  FIG. 8 . 
           [0095]      FIG. 10  represents a back view of the filtering unit of a ventilated shelving system according to the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0096]    With reference to the above mentioned Figures, the main task of the present invention is to provide a device for contamination-free removal of biological samples from a ventilated shelving storage system for laboratory animals containment cages. 
         [0097]    The device  10  for contamination-free removal of biological samples particularly from unwanted organisms from a ventilated shelving storage system  100  for laboratory animals containment cages  200  according to an embodiment the present invention comprises a support frame  11 , a sampling means  20 , for the analysis of the unwanted organisms captured by the capturing means  23 , which is arranged within the capturing portion  24  of a capturing scaffold (support)  22 . 
         [0098]    Contamination-free according to the present application has to be understood as meaning that only material coming from the cages with the animals that is transported via the foul air is captured by the capturing means, whilst no material from outside the air system of the cage rack system can be captured by the capturing means. In this way, wrong (i.e. positive but false) results are avoided. 
         [0099]    Contamination-free also means that the personnel taking the sample is not contaminated by potentially dangerous biological material from the animals in the cage rack system. The capturing means is only exposed to biological material from the cages when it is in its operating position inside the filtering unit. Outside the operating position the capturing means is covered by the sheath in order to prevent both contamination of the sample and contamination of the personnel. 
         [0100]    Unwanted organisms in the sense of the invention comprise small parasitic animals or single cell parasites including their eggs and larvae, bacteria, fungi, viruses or prions and other biological pathogens. 
         [0101]    Biological samples are entire organisms or parts of them like cellular organelles or macromolecules like polypeptide, nucleic acids, lipids, carbohydrates or small molecules. 
         [0102]    The capturing means is designed to collect from the foul air flowing through the filtering unit biological materials. In this respect the capturing means might be a membrane, tissue, sponge, swab, paper, grid or any other useful structure made of organic or synthetic material like cotton, cellulose or synthetics or metal. Also electronic devices such as sensors or microchips might be used as the capturing means. The capturing means might be covered by an adhesive in order to better collect biological materials. 
         [0103]    With reference to  FIG. 1 , a ventilated cage rack system  100  is disclosed in the following. 
         [0104]    According to a preferred embodiment of the present invention, a ventilated shelving storage system  100  for laboratory animals containment cages  200  comprises a load-bearing structure  101  for supporting a plurality of cages  200  and an air guidance means  300  comprising a filtering unit  305 . The ventilated shelving storage system according to the invention further comprises the device  10 . 
         [0105]    This is further illustrated in the above-mentioned figures as a non-limiting example, wherein the ventilated shelving system  100  comprises a load-bearing structure  101  suitable for supporting in a tidy array a plurality of cages  200  for containing laboratory animals. 
         [0106]    The cage shelving system further comprises air guidance means  300  comprising at least an air supply duct  301  for supplying clean air to the cages  200  and an air return duct  302  for collecting exhaust air coming from the cages  200 . 
         [0107]    Said air guidance means  300  of the ventilated rack system are preferably in communication with the centralized heating ventilation and air conditioning (HVAC) system, so that the air supplied to the air guidance means  300  is clean air coming from the centralized HVAV system. 
         [0108]    Similarly, a plurality of vertical ducts for the air discharged from the cages  200  convey the foul air from the cages into the return exhaust air duct  302 . 
         [0109]    Again with reference to  FIG. 1 , the air guidance means  300  further comprise a filtering unit  305  which filters the air coming from the ventilated cages  200 . 
         [0110]    As shown in  FIG. 1 , the filtering unit  305  preferably comprises a box-shaped containment structure or case  306  advantageously fitted with a removable wall to give ready access to one or more filter elements contained inside the containment case  306 . 
         [0111]    The filter element, or each of the filter elements if there is more than one, advantageously consists of a frame supporting a material suitable for filtering the particles contained in the foul air. 
         [0112]    The shape and the degree of separation of the filter elements can vary according to need, depending on the size of the ventilated shelving storage system, the level of pollution predicted in the air and various other parameters, based on experience. 
         [0113]    With reference to  FIG. 1 a   , an example of a typical air filtering unit  305  of a ventilated shelving system of the type considered herewith is shown. 
         [0114]    The air filtering unit  305  preferably comprises a containment case  306 , an inlet duct  307  connected to the plenum  302  through which the exhaust air coming from the cages  200  is fed to the filter unit, a pre-filter  308  and an HEPA filter  309 . 
         [0115]    The air coming from the inlet duct  307  is moved by a fan  310 , the air passes through the pre-filter  308  and then through the HEPA filter  309 . 
         [0116]    As to a device  10  according to the general concept of the present invention,  FIG. 2 a    shows an example thereof. The support frame  11  as part of the device  10  according to the present invention is shown. The support frame  11  is adapted to reversibly hold said sampling means  20  by means of the guiding means  13  thus allowing to positioning the capturing means  23  at a preferred capturing position  25  which is situated within an aperture  12  provided on the support frame system  11 . Furthermore, in  FIG. 2 b    an example at the general concept of sampling means  20  as part of the device  10  is shown. The sampling means comprises the capturing means  23  supported by a capturing scaffold (support)  22 , and the capturing sheath  21 . 
         [0117]    With reference to  FIG. 2 c    an example of the device  10  comprises the support frame  11  and sampling means  20  as shown in  FIGS. 2 a  and 2 b    is shown. With respect to the sampling means  20   FIGS. 2 b  and 2 c   . The guiding means could as well be a tubular structure guiding a cylindrical capturing scaffold with a cylindrical or spheroidal capturing means in a sliding manner. The frame might hold several tubular guiding means arranged side by side in a parallel fashion in order to cover several positions within the aperture. 
         [0118]    According to a preferred embodiment of the device  10  according to the present invention, said capturing scaffold  22  is inserted into the sheath  21  and is suitable to be moved in a sliding manner with respect to the sheath  21  to a capturing position  25  located in the aperture  12 , between a closed position in which said capturing portion  24  containing the capturing means  23  is completely inserted into the sheath  21  and, an open position in which said capturing portion  24  containing the capturing means  23  is completely exposed to the air flow, comprising the area of the aperture  12  not covered by the capturing portion  24  and the flow passage area  14  of the ventilated shelving storage system  100 . 
         [0119]    Sliding in the sense of the invention means easily movable within a conducting structure like a rail, a groove or the like. 
         [0120]    With reference to  FIG. 2 d   , a preferred embodiment of the device  10  according to the present invention is shown. More particularly,  FIG. 2 d    shows how the device  10  is inserted into/removed from the filtering unit  305 . 
         [0121]    According to a further embodiment of the invention the filtering unit  305  comprises a containment case  306  wherein said support frame  11  of said sampling collection device  10  is configured to be inserted in a sliding manner into said containment case  306 . 
         [0122]    Additionally, the filtering unit  305  of the ventilated shelving storage system of the resent invention comprises a pre-filter  308 , said device  10  being inserted into said filtering unit  305  underneath said pre-filter  308 . 
         [0123]    In more detail, the device  10  according to the present invention is preferably inserted into the filtering unit  305  underneath the pre-filter  308 , thus capturing particles of the potentially contaminated air coming from the plenum  302  and entering the inlet duct  307 . 
         [0124]    Said device which is preferably a planar plate is also insertable underneath the pre-filter of filtering units of existing ventilated shelving storage systems produced in the past and already provided to research laboratories. Therefore, the technology object of the present invention as described herewith can also be used in association with all ventilated shelving systems having said filtering units of the kind delivered to the market in the past. The possibility of retrofitting allows all users of such ventilated shelving systems to take advantage of the new technology. 
         [0125]    According to a preferred embodiment of the present invention the sampling means  20  is associated in a removable manner with the support frame  11 . 
         [0126]    With reference to  FIGS. 3 and 4 , the device  10  according to the present invention advantageously comprises a support frame  11  which is configured to be removably inserted into the containment case  306  of said filtering unit  305 . 
         [0127]    According to a preferred embodiment of the present invention the device  10  is associated in a removable manner to said filtering unit  305  of the ventilated shelving storage system  100 . 
         [0128]    According to the present invention said filtering unit  305  preferably comprises a containment case  306 , and said support frame  11  of said sampling collection device  10  is configured to be inserted in a sliding manner into said containment case  306 . 
         [0129]    As shown in  FIG. 2 , said support frame  11  is configured to be slidingly inserted into and or removed from the containment case  306  of the filtering unit  305 . 
         [0130]    According to a preferred embodiment of the present invention the ventilated shelving storage system  100  comprises a filtering unit  305  in turn comprising a pre-filter  308 , said device  10  being inserted into said filtering unit  305  underneath said pre-filter  308 . 
         [0131]    According to a preferred embodiment of the present invention the support frame  11  comprises one or more seats  13   a  for receiving one or more sampling means  20  and further comprises at least one aperture  12  adjacent to said one or more seats  13   a.    
         [0132]    Preferably, said sampling means  20  comprises a sheath  21 , a capturing scaffold  22  associated to said sheath  21 , and a capturing means  23  associated to the capturing portion  24  of said capturing scaffold  22 . 
         [0133]    According to  FIGS. 3 and 4 , depicting a preferred embodiment of the present invention, when the containment case  306  is substantially box-shaped, with a rectangular horizontal cross-section, the support frame  11  of the device  10  advantageously is a substantially planar plate with a substantially rectangular profile. 
         [0134]    The support frame  11  is further provided with at least one aperture  12 . 
         [0135]    According to a preferred embodiment said guiding means  13  comprise straight and elongated plates, each seat  13   a  being delimited by a couple of straight and elongated plates. 
         [0136]    According to a preferred embodiment the support frame  11  comprises a substantially planar plate with a substantially rectangular profile comprising a first short edge  11   a , a second short edge  11   b , a first long edge  11   c  and a second long edge  11   d  connecting said short edges  11   a ,  11   b.    
         [0137]    According to a preferred embodiment said support frame  11  further comprises at least one flow passage area  14 . 
         [0138]    With reference to  FIG. 2 , the support frame  11  is conceived in order to be inserted with its second short edge  11   b  positioned forward, so that the said second short edge  11   b  is the first to enter the containment case  306 . 
         [0139]    The other, first short edge  11   a , is therefore facing the outside of the containment case  306  of the filtering unit  305  once the support frame  11  is inserted therein. 
         [0140]    According to  FIGS. 3 and 4 , the support frame  11  is provided with at least one aperture  12 . 
         [0141]    In more detail, when the support frame  11  is inserted into said containment case  306  of said filtering unit  305  said aperture  12  is positioned where the air of the inlet duct  307  enters the pre-filter. This is the preferred capturing position  25  to collect airborne particles from the foul air. 
         [0142]    In any case, said at least one aperture  12  defines an area which, once the supporting frame  11  is in its open position, i.e. completely inserted into the containment case  306  of the filtering unit  305 , is entirely passed by part of the air flow which goes through the filtering unit  305 . 
         [0143]    Preferably, and according to the preferred technical characteristics of the filtering unit  305 , said support frame  11  further comprises at least a flow passage area  14  provided close to the second short edge  11   b  of said support frame  11 , so that once the support frame  11  is completely inserted into the containment case  306  of the filtering unit  305 , and therefore it is in its operative position, the air flowing into the filtering unit can freely pass through the said at least one flow passage  14 , so that the air flow which goes through the filtering unit  305  is not negatively affected by the presence of the device  10 . 
         [0144]    When two apertures  12  are provided on said supporting frame  11 , once the supporting frame  11  is completely inserted into the containment case  306  of the filtering unit  305 , and therefore it is in its operative position, a proportion of the air flowing into the filtering unit will flow through the entire area of both said apertures  12 . 
         [0145]    The device  10  according to the present invention further comprises sampling means  20 . 
         [0146]    The support frame  11  is configured to support said sampling means  20  by a guiding means  13 . 
         [0147]    In more detail, sampling means  20  are associated in a removable manner to said support frame  11 . Preferably, according to the preferred embodiment shown in  FIGS. 3 and 4 , the support frame  11  is provided with guide means  13  so that said sampling means  20  can be inserted into the support frame  11  in a sliding manner guided by said guiding means  13 , that defines a seat  13   a  for receiving said sampling means  20 . 
         [0148]    Preferably, said guiding means  13  comprises straight and elongated plates arranged parallel to each other and parallel to the short edges  11   a ,  11   b  of the frame  11 . Two parallel plates define a seat  13   a . The guiding means  13  could also be formed like a tube guiding a sampling means  20  that is cylindrically shaped. 
         [0149]    According to the example disclosed herewith, the support frame  11  is provided with two seats  13   a , positioned side by side on said frame, for receiving two of said sampling means  20 . Said at least one seat  13   a  for receiving said at least one sampling means  20  is provided on the support frame  11  adjacent to said at least one aperture  12 . 
         [0150]    The possibility to insert more than one sampling means  20  at the same time on the support frame  11  allows the technician to perform a different laboratory test on each sampling means  20 . 
         [0151]    Having more than one samples allows to test overlapping time periods. Additionally, it allows to retain a so called back-up sample in case the primary sample is lost for example in the analyzing laboratory. 
         [0152]    According to  FIGS. 5 and 6 , the sampling means  20  in turn comprise a sheath  21  and a capturing scaffold capturing scaffold  22  associated to said filter sheath  21  and in turn supporting a capturing means  23 . 
         [0153]    According to a preferred embodiment of the present invention, the sampling means  20  comprises a sheath  21 , a capturing scaffold  22  associated to said sheath  21 , and a capturing means  23  associated to said capturing portion  24 . More specifically, the sheath  21  is configured as a folder, and the capturing scaffold  22  is slidingly movable with respect to said sheath  21  between a resting position in which the capturing scaffold  22  is completely inserted into said sheath  21  and an operative position in which the capturing scaffold  22  is at least partially positioned outside said sheath  21  so that the capturing means  23  is completely exposed outside the sheath  21 . 
         [0154]    In order to provide the possibility to slide the capturing scaffold  22  with respect to the sheath  21 , the capturing scaffold  22  extends outward the sheath  21  at the first end  22   a , opposite to the second end  22   b  provided with the capturing means  23 . The capturing scaffold  22  can therefore be handled by the user as will be better described in the following with reference to  FIGS. 7 to 9 . 
         [0155]    The device  10  according to an embodiment of the present invention comprising the support frame  11  and two sampling means  20  associated to said frame  11  is shown in  FIG. 7 . 
         [0156]    Each of said sampling means  20  is inserted in one seat  13   a  provided on said support frame  11 , and the capturing scaffold  22  of each of said sampling means  20  is in its operative position in which the capturing scaffold  22  is at least partially extracted from said sheath  21  so that the capturing means  23  is completely exposed outside the sheath  21 , the capturing scaffold  22  projecting into the aperture  12  so that the capturing means  23  is entirely seeped through by the air flow which goes through the filtering unit  305 . 
         [0157]    With reference to  FIG. 8 , when the user wants to extract the samples from the frame, he can grasp the first end  22   a  of capturing scaffold  22  which projects outward from the sheath  21  and pull it outwardly thus obtaining that the second end  22   b  of the carrying element  22  slides into the sheath  21 , the capturing scaffold  22  moving from its operative position to its resting position in which the membrane filter  23  is completely inserted into said sheath  21 . 
         [0158]      FIG. 9  is a bottom view of  FIG. 8 . 
         [0159]    Once the capturing scaffold  22  is in its resting position and the membrane filter  23  is completely inserted into said sheath  21 , the first end  22   a  of the capturing scaffold  22  can be folded and secured to the sheath  21  in order to prevent unwanted movements of the capturing scaffold  22  itself. 
         [0160]    According to a preferred embodiment of the present invention, the support frame  11  is made of metallic material, e.g. aluminum, steel, stainless steel and any other suitable material, while the sheath  21  and the capturing scaffold  22  are preferably made of cardboard, plastic or any other suitable, preferably disposable, material. Due to the possibility to completely insert the capturing scaffold  22  inside the sheath  21  before and after utilizing the sample means  20 , it is assured that the capturing means  23  is fully protected before use and protected from contaminating particles. 
         [0161]    In the same way, the possibility to completely retract the capturing scaffold  22  inside the sheath  21  when the user wants to extract the sampling means  20  from the frame  11  guarantees the safety of the operators while handling the samples. 
         [0162]    A ventilated shelving storage system  100  for laboratory animals containment cages  200  comprising the device  10  is a further object of the present invention. 
         [0163]    According to a preferred embodiment, the capturing scaffold  22  is inserted into the sheath  21  and is movable in a sliding manner with respect to the sheath  21  to a capturing position  25  located in the aperture  12 , between a closed position in which said capturing portion  24  containing the capturing means  23  is completely inserted into the sheath  21  and an open position in which said capturing portion  24  containing the capturing means  23  is completely exposed to the air flow  500 , comprising the area of the aperture  12  not covered by the capturing portion  24  and the flow passage area  14  of the ventilated shelving storage system  100 . 
         [0164]    In more detail, it is also part of the present invention a ventilated shelving storage system  100  for laboratory animals containment cages  200  comprising air guidance means  300  in turn comprising a filtering unit  305 , the device  10  being removably associated to said filtering unit  305 . 
         [0165]    It is a further object of the present invention to provide a method for contamination-free removal of biological particles in a ventilated shelving storage system for laboratory animals containment cages. 
         [0166]    The method according to an embodiment of the present invention comprises the following steps:
       providing a ventilated shelving storage system  100  for laboratory animals containment cages  200  comprising air guidance means  300  in turn comprising a filtering unit  305 ;   providing a device  20  comprising a support frame  11  provided with at least one aperture  12 , at least one sheath  21  removably associated to said support frame  11 , at least one capturing scaffold  22  associated to said sheath  21 , and at least one capturing means  23  associated to said at least one capturing scaffold  22 ;   positioning said at least one capturing scaffold  22  in an operative position in which the capturing scaffold  22  is at least partially extracted from said sheath  21  and projects into the aperture  12  of the support frame  11  so that said at least one capturing means  23  is entirely intercepted by (exposed to) the air flow which goes through the filtering unit  305 .       
 
         [0170]    According to the present invention, once the technician wants to extract the sample device from the filtering unit  305  the method comprises the following steps:
       moving said capturing scaffold  22  from its open position to a closed position in which the capturing means  23  is completely inserted into said sheath  21 ;   removing the sheath  21  from the support frame  11  and then from the filtering unit  305 .       
 
         [0173]    In more detail, the method for contamination-free removal of biological samples particularly from unwanted organisms from a ventilated shelving storage system  100  for laboratory animals containment cages  200 , comprises the following steps:
       providing a sampling means  20  for said device  10 ,   positioning (moving) the sampling means  20  of said device  10  from the closed position to the open position   collecting biological samples,   positioning (moving) the sampling means  20  of said device  10  from the open position to the closed position,   pulling off the sampling means  20  from the filtering unit  305 ,   transferring the sampling means  20  to a ventilated hood,   shifting the capturing scaffold  22  comprising the capturing means  23  to the open position,   transferring the capturing means  23  to a reaction vessel for analysis of biological samples of unwanted organisms, preferably by PCR.       
 
         [0182]    Material obtained with the device is optionally further processed. For example, cells may be lysed, and the cell lysate may be separated and analyzed for characteristic components such as proteins or DNA. The biological material may be analyzed by methods well known to the person skilled in the art, for example, via amplification of pathogen-specific nucleic acid sequences by PCR; culture of pathogens on appropriate growth media, followed by isolation and either biochemical or histological assays; mass spectrometer-based detection of pathogen-specific components, such as MALDI-TOF; use of DNA hybridization techniques, such as for example Northern or Southern blot assays or hybridisation on DNA arrays as well as assays based on protein detection including but not limited to Ion Exchange Chromatography, Gel Filtration Chromatography, Affinity Chromatography, High Pressure Liquid Chromatography (HPLC) or immunoassays, such as enzyme-linked immunosorbent assays (ELISA), Western blot analysis or Immunoprecipitation. 
         [0183]    Furthermore, a biosensor may be employed to detect the biological material. In theory a large number of these tiny biosensors would form an array capable of detecting any one of the known viruses, bacteria or parasites and would provide rapid identification as well as digital output to some controller or computer. Microbial biosensors would be designed with analytes that have a specificity for microbiological components such as surface components or specific metabolites. The mechanisms by which the microbes are detected could include electrochemical (amperometric, conductimetric or potentiometric) or electromagnetic (optical or mass) means. 
         [0184]    In a preferred embodiment, pathogens are identified via amplification of pathogen-specific nucleic acid sequences. Methods of amplification of nucleic acid sequences include, for example, RT-PCR and its various modifications such as qRT-PCR (also referred to as Real Time RT-PCR). PCR is well known in the art and is employed to make large numbers of copies of a target sequence. 
         [0185]    Due to the device  10  according to the present invention as above described, several advantages are therefore achieved. 
         [0000]    As it has been said, the device according to the present invention allows to perform sampling operations in a contamination-free way. 
         [0186]    The device allows the operator to extract the sampling from the shelving system in a safe way at the same time preserving the membrane filter thus avoiding unwanted alteration of the sample. 
         [0187]    Due to the structure of the device, and in particular of the support frame  11  which is preferably provided with a at least one flow passage  14 , the air flow which goes through the filtering unit  305  is not negatively affected by the presence of the device  10 . 
         [0188]    Furthermore, the device according to the present invention can be easily associated to existing shelving systems, in particular to the filtering unit of already installed shelving systems, and therefore allows to retrofitting existing apparatuses. 
         [0189]    Whilst the present invention has been clarified by means of the above description of the embodiments thereof as depicted in the drawings, the present invention is not limited to the embodiments as disclosed above and depicted in the drawings; the scope of the present invention is rather defined by the appended claims.