Abstract
Device for spermatozoa selection comprising a first chamber configured to receive a first, seminal fluid; a second chamber configured to receive a second fluid, the second chamber being in fluid communication with the first chamber by means of at least one duct having a first opening to the first chamber and a second opening to the second chamber; and a displacement means adapted to displace at least some of the first, seminal fluid towards the first opening.
Claims
1. A device for spermatozoa selection having a longitudinal axis, an upper end, and a lower end, the device comprising: a first chamber configured to receive a first, seminal fluid; and a displacement element configured to be inserted within the first chamber, the displacement element defining a second chamber configured to receive a second fluid, the second chamber being in fluid communication with the first chamber by at least one duct having a first opening to the first chamber and a second opening to the second chamber, wherein the displacement element is adapted to displace at least some of the first, seminal fluid towards the first opening; wherein the duct is configured to provide a fluid communication between the first chamber and the second chamber to allow spermatozoa to move from the first chamber to the second chamber; wherein, in a cross section along the longitudinal axis of the device, the duct comprises at least a first segment that extends in a first direction having a directional component towards the upper end of the device and at least a second segment that extends in a second direction having a directional component towards the lower end of the device; and wherein the first segment is prior to the second segment when following the duct from the first opening to the second opening.
2. Device according to claim 1, wherein the first chamber is provided by a vessel with a closed lower end.
3. Device according to claim 1, wherein the displacement element is slidably received in the first chamber.
4. Device according to claim 1, wherein the displacement element is adapted to displace the first, seminal fluid such that the upper surface of the first, seminal fluid is arranged at a predetermined distance from the first opening.
5. Device according to claim 1, wherein the displacement means comprises a displacement body.
6. Device according to claim 1, wherein the displacement element comprises a shaft for manipulating the displacement element, wherein the shaft is hollow and opens out into the second chamber.
7. Device according to claim 1, wherein the second chamber is formed in the displacement element.
8. Device according to claim 1, wherein the duct has a cross section of an inverted U, a first leg of said U extending to the first chamber and a second leg of said U extending to the second chamber.
9. Device according to claim 1, wherein the displacement element comprises an upwardly extending rim and wherein the shaft is connected with a ring-shaped cover, wherein the duct is formed between the rim and the cover.
10. Device according to claim 1, wherein the vessel is provided with a first scale for assessing a volume of the first, seminal fluid in the first chamber.
11. Device according to claim 10, comprising a second scale for assessing travel of the displacement element.
12. Device according to claim 11, wherein the second scale indicates the required travel of the displacement element dependent upon the volume indicated by the first scale.
13. Device according to claim 1, further comprising a plug for sealing the first chamber relative to the environment.
14. Method for selecting mobile cells using the device of claim 1 including the steps of: (a) providing a first fluid comprising motile cells in the first chamber; (b) providing a buffer medium in the second chamber; and (c) connecting the first chamber and the second chamber by a liquid connection; and (d) displacing at least some of the first fluid towards, proximate or to the first opening of the duct with the displacement element.
15. The method of claim 14, wherein the first fluid is substantially unmixed human ejaculate.
16. Device according to claim 1, wherein the first chamber is provided by a vessel, and a gap is formed between the displacement element and an interior wall of the vessel.
Description
(1) The Figures described below disclose embodiments of the invention for illustrational purposes only. In particular, the disclosure provided by the Figures is not meant to limit the scope of protection conferred by the invention. The Figures are schematic drawings only and embodiments shown may be modified in many ways within the scope of the claims.
(2) FIG. 1: Sectional view of a prior art selection device disclosed in WO 03/031594.
(3) FIG. 2: Exploded view of the prior art selection device shown in FIG. 1.
(4) FIG. 3A: Plan view of a device for spermatozoa selection according to an embodiment of the present invention.
(5) FIG. 3B: Exploded view of the device shown in FIG. 3A.
(6) FIG. 4: Plan view of the displacement means of the device shown in FIGS. 3A and 3B.
(7) FIG. 5: Enlarged sectional view illustrating the lower portion of the displacement means shown in FIG. 4.
(8) FIG. 6: Enlarged sectional drawing of the lower portion of the device shown in FIGS. 3A and 3B.
(9) FIGS. 7A-7C: Sequence of schematic sectional drawings showing the usage of a device according to the present invention.
(10) FIG. 7D: Schematic drawing illustrating spermatozoa selection.
(11) FIG. 8A-8E: Sectional drawings showing the lower portion of a selection device according to various embodiments of invention.
(12) FIG. 9: Plan view showing a vessel for selection devices according to embodiments of the present invention, the vessel being provided with first and second scales.
(13) FIG. 10: Plan view showing a displacement means for selection devices according to embodiments of the present invention, the displacement means being provided with a scale.
(14) FIG. 11A: Plan view showing a kit according to embodiments of the present invention.
(15) FIG. 11B: Exploded view of the kit shown in FIG. 11A.
(16) FIG. 12A: Sectional drawing of the selection device according to another embodiment of the invention.
(17) FIG. 12B: Sectional drawing showing an enlarged view of the lower portion of the selection device of FIG. 12A.
(18) FIG. 13A: Plan view of a device for spermatozoa selection according to another embodiment of the present invention with the displacement means fully introduced into the vessel.
(19) FIG. 13B: Section I-I of FIG. 13A.
(20) FIG. 13C: Perspective view of the device for spermatozoa selection according to FIGS. 13A and 13B.
(21) FIG. 13D: Plan view of a device for spermatozoa selection according to FIG. 13A with the displacement means at an upper end of the vessel.
(22) FIG. 13E: Section II-II of FIG. 13D.
(23) FIG. 14A: Sectional drawing showing a funnel structure according to aspects of the invention.
(24) FIG. 14B: Sectional drawing showing the functional principle of the funnel structure illustrated in FIG. 13A.
(25) FIG. 15A: Plan view showing a funnel structure incorporating further aspects of the invention.
(26) FIG. 15B: Section III-III of FIG. 15A.
(27) FIG. 16: Table comparing spermatozoa concentrations achieved when using fresh, untreated ejaculate and ejaculate that rested for 15 to 30 min.
(28) FIG. 3A shows a plane view of a device 101 for spermatozoa selection according to embodiments of the present invention. As shown, the device may be rotationally symmetric with respect to its longitudinal axis A.
(29) As shown in the exploded view illustrated in FIG. 3B, the device 101 comprises a first chamber 103 and a displacement means 105. The first chamber 103 may be formed by an interior portion of a lower end of a vessel 104, which preferably surrounds the displacement means 105 when the device 101 is in an assembled state (see FIG. 3A). While the vessel 104 is shown with a hemispherical lower end, it is noted that the lower end of the vessel may have any suitable shape. As such, the vessel may have a conical, generally conical, truncated, rounded or flat lower end. Furthermore, the lower end of the vessel may be formed such that the vessel is self-standing.
(30) FIG. 4 shows a plan view of the displacement means 105 illustrated in FIGS. 3A and 3B. As shown, the displacement means 105 may comprise a displacement element 109 located at a lower portion 107 thereof. The lower portion 107 may further be provided with a second chamber 115, which is provided above the displacement element 109 in the illustrated embodiment and formed integrally therewith.
(31) The displacement means 105 may further comprise a shaft 123 for manipulating and holding the displacement means. As such, the shaft 123 may be used by a user to slide the displacement means into the vessel 104 and the first chamber 103 (see FIG. 3A). When a hollow shaft 123 as shown in the Figures is used, the atmosphere can be fluidly connected with the second chamber 115 such that the second fluid may be filled into and/or extracted from the second chamber through the shaft 123. The shaft can be provided with one or several spacers 125 in order to center the displacement means 105 in the vessel 104. The spacers ensure that the displacement means 105 is received in the vessel 104 in a coaxial manner. It should be noted, however, that also other elements connected to the vessel and/or the displacement means, for example the ring-shaped cover 119, may be used for this purpose.
(32) As further shown, for example, in FIG. 3A, a plug 127 may be used to close the vessel 104. The plug 127 may be part of the displacement means and can be attached thereto in a fixed or slidable manner. Alternatively, the plug 127 may be formed integrally with the displacement means 105, for example, as part of the shaft 123. The plug may close the vessel 104 in a sealing, for example airtight, manner.
(33) The details of the lower portion 107 of the displacement means are schematically illustrated in the enlarged view of FIG. 5. As shown, the second chamber 115 may be surrounded by a rim 117 having an upper end surface, an outer wall surface and an inner wall surface. A ring-shaped cover 119 may extend around at least part of the outer wall surface, the upper end surface and the inner wall surface of the rim 117 at a predetermined distance, forming a duct 111. The displacement element 109 and the second chamber 115 are integrally formed in the shown embodiment. Any suitable material may be used, for example plastic or glass.
(34) Distance piece 121 allows maintaining the ring-shaped member 119 at the predetermined distance in order to provide the duct 111 with a predetermined width. The ring-shaped cover may be formed integrally with or connected to the shaft and may be formed of any suitable material, for example plastics or glass. The shaft with the ring-shaped cover may be connected to the displacement element in a fixed manner.
(35) FIG. 6 schematically illustrates a cross section of the device along its longitudinal axis A. As shown therein, the duct 111 substantially has the shape of an inverted U, a first leg extending to the first chamber and a second leg extending to the second chamber. The duct 111 has a first opening 112 to the first chamber 103 and a second opening 113 to the second chamber 115. The openings 112, 113 are preferably ring-shaped. As illustrated, the U-shaped duct 111 may extend further into the second chamber 115 than into the first chamber 103. The arrows shown in FIG. 6 adumbrate the path along which spermatozoa may travel from the first chamber 103 to the second chamber 115.
(36) Usage of the device for spermatozoa selection according to embodiments of the present invention is further illustrated by the schematic drawings of FIGS. 7A-7C. As shown in FIG. 7A, the first, seminal fluid 135 may be received in the first chamber 103 formed at the lower end of the vessel 104. Since the first, seminal fluid may be, for example, semen of a patient, the provided volume may vary considerably.
(37) Once the first, seminal fluid 135 is received in the first chamber 103, the displacement means 105, in particular the displacement element 109, may be introduced into said first chamber 103 until the first, seminal fluid 135 is located proximate the first opening 112. In the illustrated example, the displacement means is inserted by a distance L into the first, seminal fluid. The upper surface of the first, seminal fluid, as a consequence, is displaced a distance D towards the first opening 112 (see FIG. 7B). In the illustrated embodiment, the first, seminal fluid 135 does not reach the first opening 112 entirely. Rather, a space S remains between the first, seminal fluid 135 and the first opening 112, which is subsequently covered by second fluid 136 flowing through the duct 111 when the second chamber 115 is filled. This prevents the first, seminal fluid from being drawn into the duct 111 by capillary action and, therefore, avoids that spermatozoa reach the second chamber 115 without passing the selection process. However, displacing the first, seminal fluid 135 to contact the first opening 112 may be considered for some applications. With the selection device of the present invention, the space S between the first, seminal fluid 135 and the first opening 112 may be equalized for a broad range of volumes of first, seminal fluid provided in the first chamber 135 by inserting the displacement element 109 to the appropriate depth L. Since, the volume of second fluid 136 can be kept constant and reproducible results can be obtained.
(38) As shown in FIG. 7C, the second fluid, for example, a buffer medium is subsequently provided in the second chamber 115. As mentioned above, the second fluid preferably is drawn into the duct 111 by capillary action and/or due to the pressure exerted when filling it into the second chamber, for example, along the shaft 123 by means of a pipette. Accordingly, the duct 111 establishes a liquid bridge between the first chamber 103 and the second chamber 115, allowing spermatozoa to move along the path indicated by the arrows shown on FIGS. 6 and 7C. As schematically illustrated in FIG. 7D, spermatozoa or other motile cells in the first fluid 135 will swim or flow from the first chamber through the duct 119 into second fluid 136 contained in the second chamber.
(39) Once spermatozoa are separated (e.g., after waiting for 15-120 min.) the second fluid may be withdrawn from the second chamber, for example, by means of a pipette introduced through the shaft 123. The first chamber 103 may be sealed relative to the environment (e.g. by closing the open upper end of the vessel 104 with the plug 127, as shown in FIG. 3A) in order to prevent first, seminal fluid 135 from being drawn into the second chamber 115 when collecting the fluid contained therein.
(40) As will be appreciated by those skilled in the art, the sequence of the steps described above may be changed in embodiments of the invention. For example, the second fluid 136 may be received in the second chamber 115 before the displacement means is introduced into the first chamber 103. Furthermore, the displacement means may be introduced into the first chamber before the first, seminal fluid 135 is received therein.
(41) The ring-shaped cover 119 preferably is located at least 0.1 mm, preferably at least 0.2 mm, and more preferably between 0.3 and 0.4 mm from the rim. Accordingly, the duct 111 preferably has a width of at least 0.1 mm, more preferably at least 0.2 mm and most preferably between 0.3 and 0.4 mm. As will be understood by the skilled person, the optimal widths will depend on the materials and the fluids employed, as both may influence capillary action. The length of the duct 111 preferably is between 15 to 40 mm, more preferably between 20 to 38 mm, most preferably between 25 to 35 mm as measured from the first opening to the second opening when considering a cross section of the displacement element along longitudinal axis B.
(42) The outer surface of the lower portion of the displacement means that is introduced into the first chamber, in particular the outer surface of the displacement element 109, may be shaped in different ways, for example in a substantially spherical, hemispherical, conical, truncated or cylindrical manner. Also the inner surface of the first chamber 103, in particular the inner surface of the closed lower end of the vessel 104 may have various shapes. As such, the inner surface may be, inter alia, substantially hemispherical, conical, truncated or cylindrical. Depending on the particular requirements, the above-mentioned shapes may be combined as desired. For example, rounded displacement means may be used with conical vessels and vice-versa.
(43) FIGS. 8A-8E illustrate different embodiments of displacement means for devices according to the present invention, the forms of which may also be combined. As shown in these Figures, a gap G may be formed between the lower portion of the displacement means 105 and the interior wall of the vessel 104. More specifically, the gap G preferably is formed between the displacement element 109 and the vessel 104.
(44) As shown in FIGS. 8A-8C, the gap G may be variable. In this case, the gap G preferably is formed such that a relatively large fraction of the first, seminal fluid received in the first chamber is displaced from the bottom of the first chamber proximate the first opening of the duct. The gap G may provide an enlarged collection space proximate the first opening. For this purpose, the width of the gap G preferably increases from a lower part towards an upper part of the first chamber 103 when the displacement means 105 is fully inserted. For example, the displacement element 109 may follow the inner surface of the first chamber at the bottom of the vessel 104 (i.e. at the closed lower end) and separate from the first chamber proximate the first opening 112 in order to form the collection space (see, for example, FIG. 8A).
(45) However, as shown in FIGS. 8D and 8E, the shape of the displacement element 109 may also match the shape of the lower end of the vessel 104. For example, both elements may have a generally hemispherical (FIG. 8D) or generally conical (FIG. 8E) shape along at least their contacting segments. As further apparent from FIGS. 8A-8E, the displacement means 109 may have different sizes and displacement volumes, the displacement means 109 of FIGS. 8D and 8E being somewhat shorter along the longitudinal axis B. It should be noted that any of displacement means described above (e.g., the displacement means illustrated in FIGS. 8A-8E) may be shortened or elongated in order to provide the displacement element 109 with a desired displacement volume and/or shape.
(46) As further shown in FIGS. 9 and 10, the device may be provided with first and second scales 129, 131 for assessing the volume of the first, seminal fluid provided in the first chamber and the travel of the displacement means relative to the vessel 104, respectively. In the exemplary embodiment shown in FIGS. 9 and 10, the first scale 129 is provided on the vessel 104 and the second scale 131 is provided on the displacement means 105 (e.g., at an upper portion). However, the second scale may also be located on the vessel 104, for example, at an upper portion thereof. While the second scale 131 is described above as being located at the upper portion of the vessel 104 and the displacement means 105, it should be noted that the second scale may be located at any suitable height along the longitudinal axis of the device.
(47) In embodiments of the invention, the second scale 131 may indicate the travel required for the displacement means dependant upon the volume of first, seminal fluid provided in the first chamber. Users of the device will then be able to assess the volume of first, seminal fluid in the first chamber by means of the first scale and, subsequently, the travel required for the displacement means on the second scale without having to perform intermediate steps or calculations.
(48) In some cases, the distance to which the displacement means has to be inserted will not be inversely proportional to the volume received in the first chamber but, for example, correlate in a somewhat reciprocal manner. The distance between adjacent gradations of the second sale 131, therefore may vary and, for example, become smaller for larger volumes.
(49) With the device of the present invention, the same volume of second fluid may be required, irrespectively of the volume of first, seminal fluid received in the first chamber. As shown in FIGS. 11A and 11B, the device 101 may also comprise a pipette 140. The pipette 140 may be adapted for being inserted into the shaft 123 and may contain a defined and/or fixed volume of second fluid 136, determined such that optimal wetting of the duct is ensured. Since the fluid level in the first chamber may be adjusted with the displacement means, this volume may be fixed, regardless of the volume of first, seminal fluid provided in the first chamber. Further, the pipette 140 may be configured to inject the second fluid 136 at a predetermined speed and/or with a predetermined pressure in order to prevent formation of air bubbles in the second fluid 136. The device 101 and the pipette 140 may be provided as a kit.
(50) According to embodiments of the invention, the closure means (e.g., plug 127) may be inserted into the first chamber 103 after sealing it therewith. More specifically, the closure means may be inserted into the vessel 104 after sealing it, for example, at its open upper end.
(51) As illustrated in FIG. 12A, the closure means may be configured such that they can be inserted a predetermined maximal depth into the vessel. By way of example, the plug 227 has a lower portion with a first diameter and an upper portion with a second diameter that is larger than the first diameter. Therefore, an abutment surface is formed that abuts the upper end of the side wall of the vessel 104 and prevents further insertion of the plug when the maximal depth is reached. The illustrative embodiment further comprises an optional screw cap 228 that is provided with an inner thread 229 in order to engage an attachment means 106 of the vessel 104. As shown, the attachment means 106 may be formed by an outer thread formed on the outer surface of the vessel's wall. It should be noted that also other plugs (e.g., a generally cylindrical plug having a diameter that corresponds to the inner diameter of the upper end of the vessel 104) may be employed. Such plugs may be affixed to the cap 228 or may be formed as separate components.
(52) When the second chamber is filled in the way shown in FIG. 12B, with the level of the second fluid 136 being higher than the first opening of the duct, the positive pressure caused by inserting the plug 127, 227 into the vessel 104 may push a fixed volume of second fluid 136 located along the inner part of the duct proximate the second opening into the second chamber. As described above, the vessel 104 may be sealed thereafter, so that no additional fluid is drawn into the second chamber when the fluid contained therein is extracted.
(53) FIGS. 13A-13E illustrate a device for spermatozoa selection 101 according to another embodiment of the present invention. In FIGS. 13A, 13B, and 13C, the selection device 101 is shown with the displacement means 105 fully introduced into the vessel 104 in plan, sectional and perspective views, respectively.
(54) As shown in FIG. 13B, an ideal space S may be achieved between the first fluid 135 contained in the first chamber 103 and the opening of the duct leading to the second chamber 115 even if only small volumes of seminal fluid 135 are provided in the first chamber 103. In contrast, FIGS. 13D and 13E illustrate the selection device 101 with the displacement means 105 located in the upper part of the first chamber 103. As best shown in FIG. 13E, this configuration allows providing a relatively large volume of the first fluid 135 in the first chamber 103. Therefore, the device of FIGS. 13A-13E may provide the same functionality as the devices of FIGS. 3A-12B described above.
(55) As further shown in FIGS. 13A-13E, the vessel 104 may be closed with a cap 328, which may be provided, for example, with a bayonet fit 329 in order to attach it to a corresponding attachment structure 306 of the vessel 104. It will be noted, however, that also other means may be used in this context, as, for example, a screw-on cap, a cap with a screw-on collar, or a cap with a snap fit.
(56) The cap 328 may comprise vent holes 330. Preferably, the vent holes 330 can be closed by means of a plug 327, which is mounted on the cap 328 in the exemplary embodiment illustrated in these Figures. The plug 327 can be turned relatively to the cap 328 in order to close the vent holes 330 in an airtight manner. As such, the first chamber 103 may be sealed.
(57) As shown in FIGS. 13B and 13E, the displacement means 105 may comprise a shaft 123 with an external threading 124. Correspondingly, a through-hole with an internal threading 324 may be formed in the cap, which through-hole may be used to centre the displacement means 105 in the vessel 104. By means of the interacting external and internal threading, the displacement means 105 with the second chamber 115 forming the displacement element may be lowered or raised in the vessel, thereby allowing a user to set the correct height of the displacement means 105 in accordance with the volume of first fluid 135 provided in the first chamber 103.
(58) The vessel 104 of the device 101 of FIGS. 13A-13E is shown with a flat lower end and may be self-standing without the need of a support. However, the bottom of the vessel 104 may also be provided with other shapes, as discussed in detail above.
(59) FIG. 14A illustrates the funnel structure 170 of the present invention in an upright position, such that the funnel can be used to fill liquids into a receptacle or vessel. The funnel structure 170 has a first circumferential wall 171 and a second circumferential wall 172, which both taper towards the inside of the funnel structure 170 (i.e., towards its central axis) in a downward direction. As shown, the first circumferential wall 171 may form an outer funnel and the second circumferential wall may form an inner funnel with respect to said outer funnel. The inner and outer funnels may have generally conical shapes along at least a segment.
(60) The first and second circumferential walls may be connected by an upper wall 173. Preferably, a recuperation compartment 179 is formed between the first and second circumferential walls. The upper end of the recuperation compartment may be closed by upper wall 173 and may be open in a downward direction when the funnel structure 170 is positioned in an upright manner. One, several or all of the walls of the funnel structure may be formed from polymeric materials or glass. The walls may be formed integrally.
(61) Further, the funnel structure 170 comprises an inlet opening 175 and an outlet opening 177. The outlet opening 177 preferably has a smaller cross-sectional area than the inlet opening 175 and preferably is disposed below the inlet opening 175 when the funnel structure 170 is in the upright position, as shown in FIG. 14A. An intermediate opening 176 may be disposed between the inlet opening 175 and the outlet opening 177.
(62) Preferably, the inlet opening 175 is formed at the upper end of the second circumferential wall 172 and the intermediate opening 176 is formed at the lower end of the second circumferential wall 172. The outlet opening 177 preferably is formed at the lower end of the first circumferential wall 171.
(63) The funnel structure 170 may be provided with an attachment structure 174 for attaching the funnel to a vessel. In the illustrated example, the attachment structure 174 is provided on a cylindrical protrusion with an internal thread. The vessel 104 may be inserted into the cylindrical protrusion in order to prevent contamination of the vessel's inner walls. However, also other types of connectors and/or attachment structures may be provided, as appropriate.
(64) As shown in FIG. 14A, the funnel structure may also comprise an optional air vent 178 that fluidly connects the interior of the vessel 104 and the environment. In the shown embodiment, the air vent 178 provides a fluid connection between the interior of the vessel 104 and the recuperation compartment 179. The air vent 178 may be provided by a hole traversing the first circumferential wall 171.
(65) As further shown in FIG. 14A, the funnel structure may be attached to the vessel 104 of the selection device and used in combination therewith. The vessel 104 may be provided with attachment means 106 for this purpose. The attachment means 106 may be configured to engage the attachment structure 174 of the funnel structure 170. As illustrated, the attachment means 106 may be provided proximate the upper opening of the vessel 104 according to embodiments of the invention.
(66) The vessel 104 may be inserted into a stand 180 in order to maintain it in an upright position or may be self standing.
(67) FIG. 14B illustrates the functional principle of the funnel structure 170. When the vessel 104 and the funnel structure 170 are disposed in a horizontal position, knocked over or turned around, most or all of the liquid (e.g., the seminal fluid 135) that is contained in the vessel 104 and flows out through the outlet opening 177 of the funnel structure 170 is captured in the recuperation compartment 179. Therefore, contamination of the liquid flowing out of the vessel 104 is prevented and the liquid may be filled back into the vessel 104, e.g., by holding the funnel structure 170 and the vessel 104 in the upright manner shown in FIG. 14A.
(68) Moreover, the attachment structure 174 preferably is configured to provide a leak-proof attachment with the vessel 104, such that, when the vessel 104 is disposed in a horizontal position, knocked over and/or turned upside-down, the liquid 135 remaining in the vessel 104 does not leak through the upper opening of the vessel 104. However, the vessel 104, the funnel structure 170 and/or the stand 180 may also be configured such that the vessel's bottom is below its opening when the vessel is knocked over and/or lies horizontally. In this case, a leak proof seal between the attachment structure 174 of the funnel structure 170 and the attachment means 106 of the vessel 104 may not be required.
(69) FIGS. 15A and 15B show a further embodiment of a funnel structure in accordance with the present invention in plan and sectional views, respectively. The funnel structure 470 is similar to the funnel structure 170 of FIGS. 14A and 14B and the same reference numbers are used for some of the elements that are alike or similar. In this context, reference is made to the description of funnel structure 170 provided above in order to avoid repetitions.
(70) As can be seen from FIGS. 15A and 15B, the funnel structure 470 is configured with attachment means in the form of a bayonet fit 474 that cooperates with the corresponding attachment section 306 provided to the vessel. Accordingly, the funnel structure 470 is configured for use with the selection device 101 of FIGS. 13A-13E and the funnel structure may be attached to the vessel by the same mechanism than the cap 327.
(71) Finally, FIG. 16 shows a table in which the spermatozoa concentration achieved is reported for selections performed after letting the ejaculate rest for 15 to 30 min. and without such resting period. For the purposes of this study, the ejaculate of four different Patients (Patients A-D) has been processed with the device of the present invention. The Final concentration, indicated in the Table in millions of spermatozoa per ml, reports the concentration achieved in the second fluid after selection, which is the fluid from which the spermatozoa are then retrieved for in-vitro fertilization. Further separation steps are not required. While a different sperm sample has been used for each measurement, all patients enrolled have been shownin several previous studiesto provide sperm samples of very similar volume and quality after an abstinence period of 3 days.
(72) As can be observed, substantial improvements have been achieved in all cases in which the semen sample is used directly after ejaculation, including a tenfold higher concentration of spermatozoa. Conversely, a considerably lower concentration (up to ten times lower) is yielded when waiting for 15 to 30 min., letting the ejaculate rest in order to liquefy it. It is, therefore, preferred to introduce semen samples into the selection device of the present invention directly after ejaculation, without resting periods and/or the use of additional vessels.
(73) As will be acknowledged by the skilled person in view of the description provided above, the present invention provides improved selection devices and methods that can be used with varying volumes of seminal fluid. In particular, the device may be used for seminal fluid volumes of less than 1 ml or less than 0.5 ml without requiring dilution. The time required for separating such sperm samples may be reduced significantly, thereby decreasing chemical stress due to contact with atmospheric O.sub.2. Further, less handling steps are required and mechanical stress is reduced also.
(74) Since the first chamber may be sealed relative to the environment, contamination of the collected sample by spermatozoa with strand breaks and/or low motility is prevented. Moreover, exposure of spermatozoa to oxygen before, during and/or after the selection procedure is reduced further.
(75) Additionally, the same amount of medium may be used irrespectively of the volume of seminal fluid received in the first chamber. Thus, handling of the device is simplified and repeatable results are obtained more easily. Wetting of the fluid connection is improved, e.g., when using the pipette described above for injecting the medium, which may also lead to better results when performing the selection procedure.
(76) While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. It will be understood that changes and modifications may be made by those of ordinary skill within the scope of the following claims. In particular, the present invention covers further embodiments with any combination of features from different embodiments described above.
