US 11708560

US Patent 11708560, titled "Enhanced MSC preparations," was issued on July 25, 2023, from an application filed on December 23, 2019. The current assignee is Mesoblast International SARL, and the inventors are Samson Tom, Christopher Ton, and Alla Danilkovitch.

Abstract:
The patent generally relates to therapeutically effective preparations of mesenchymal stem cells (MSCs), methods for manufacturing these preparations, methods for screening and selecting them, and their therapeutic uses.

Independent Claims Overview:

• Claim 1: Describes a preparation containing at least 1 billion mesenchymal stem cells (MSCs). These MSCs are characterized by a specific antigen profile: less than approximately 1.25% CD45+ cells, at least approximately 95% CD105+ cells, and at least approximately 95% CD166+ cells.
• Claim 15: Covers a method of treating a subject by administering a therapeutic dose of the MSC preparation as defined in Claim 1.
• Claim 16: Outlines a method for creating therapeutically acceptable MSCs. This involves obtaining bone marrow aspirate, expanding the MSCs to produce at least one therapeutic dose, and then selecting the batch if it meets the specific antigen profile defined in Claim 1 (less than approximately 1.25% CD45+ cells, at least approximately 95% CD105+ cells, and at least approximately 95% CD166+ cells).
• Claim 17: Describes a method of making therapeutically acceptable MSCs, similar to Claim 16, but the selection criterion is a TNFRI (Tumor Necrosis Factor Receptor 1) profile of at least approximately 13 pg TNFRI per million MSCs.
• Claim 18: Details a method for making therapeutically acceptable MSCs, where the selection criterion is a viability of at least approximately 70% after a freeze-thaw cycle.
• Claim 19: Defines a method for making therapeutically acceptable MSCs, where the selection criterion is the MSCs' ability to differentiate into adipogenic, chondrogenic, and osteogenic cell types after passage expansion.
• Claim 20: Presents a method for making therapeutically acceptable MSCs, with the selection criterion being that the preparation has a normal karyotype (no chromosomal abnormalities).
• Claim 21: Describes a method for making therapeutically acceptable MSCs, where the selection criterion is that the preparation is free of pathogens.
• Claim 22: Outlines a method for making therapeutically acceptable MSCs, with the selection criterion being low residual levels of BSA (less than approximately 55 µg/mL) and trypsin (less than approximately 42 µg/mL).

CAFC 2026 Dockets:
A search of CAFC 2026 dockets for patent number 11708560 did not return any specific results, indicating no active appeals or litigation related to this patent were found in the available public records for 2026.

As of April 26, 2026, a search for litigation involving US patent 11708560 did not return any specific results on the Unified Patents portal or through general public record searches. While PACER is a valuable resource for federal court records, direct access requires an account and specific case details.

Therefore, based on the conducted searches, there is no known litigation involving US patent 11708560 at this time.

Proceedings overview

There are no PTAB proceedings on file for US Patent 11708560.

Strategic summary

As there are no PTAB proceedings on file for US Patent 11708560, all claims of the patent (Claims 1-22) remain untested and fully enforceable from a PTAB perspective. This means that a defendant facing assertion of this patent currently has the full range of prior art grounds available for a potential inter partes review or other AIA trial proceeding, should they choose to pursue that avenue. The absence of PTAB activity could indicate several things, such as the patent being relatively new, not yet having been extensively asserted, or that previous challenges have not resulted in public PTAB filings.

Recommended next steps

If you are a defendant facing assertion of US Patent 11708560, it is important to understand that all claims are currently presumed valid. Given the lack of PTAB activity, a thorough prior art search would be a critical first step to evaluate potential grounds for an AIA trial challenge (e.g., IPR or PGR), should that strategy align with your overall defense. There are no active proceedings or upcoming milestones to monitor at the PTAB for this patent.

Inventors

• Samson Tom: Employer not determinable from the patent text.
• Christopher Ton: Employer not determinable from the patent text.
• Alla Danilkovitch: Employer not determinable from the patent text.

The patent lists Mesoblast International SARL as the original assignee. Alla Danilkovitch is also mentioned as an assignor in a reassignment to OSIRIS THERAPEUTICS, INC. on 2020-01-15, suggesting she was associated with Osiris Therapeutics at some point, or her rights were assigned from her directly. This doesn't necessarily indicate all inventors departing the original assignee within 12 months, as the reassignment occurs about a month after the filing date, but it does show individual inventor assignment.

Original assignee

Mesoblast International SARL is the entity named on the issued patent.
Mesoblast is a global leader in allogeneic cellular medicines for inflammatory diseases. They are an operating company that develops and manufactures mesenchymal stem cell (MSC) therapies.
Mesoblast International SARL is currently operating.

Assignment timeline

• 2020-01-15 (executed) / recorded 2020-01-15 — Reel 051000/0839

  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS).
  • Assignor: DANILKOVITCH, ALLA; TON, CHRISTOPHER; TOM, SAMSON (Inventors)
  • Assignee: OSIRIS THERAPEUTICS, INC.
  • Correspondent: BETH M. GOLDMAN, MORRISON & FOERSTER LLP, 2000 PENNSYLVANIA AVENUE, N.W., SUITE 6000, WASHINGTON, DISTRICT OF COLUMBIA, UNITED STATES 20006-1888. This correspondent recurs frequently in patent assignment records for large operating companies.
  • Context: Transfer of inventor rights to a prior assignee. Osiris Therapeutics, Inc. is a pioneer in regenerative medicine, marketing wound and burn healing and tissue regeneration products based on mesenchymal stem cells.

• 2020-01-15 (executed) / recorded 2020-01-15 — Reel 051000/0843

  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS).
  • Assignor: OSIRIS THERAPEUTICS, INC.
  • Assignee: MESOBLAST INTERNATIONAL SARL
  • Correspondent: BETH M. GOLDMAN, MORRISON & FOERSTER LLP, 2000 PENNSYLVANIA AVENUE, N.W., SUITE 6000, WASHINGTON, DISTRICT OF COLUMBIA, UNITED STATES 20006-1888. This correspondent recurs frequently in patent assignment records for large operating companies.
  • Context: Transfer from an acquired operating company (Osiris Therapeutics was acquired by Smith & Nephew in 2019) to the current assignee, Mesoblast International SARL. This indicates a prior relationship or a sale of assets.

• 2021-12-10 (executed) / recorded 2021-12-10 — Reel 058863/0501

  • Conveyance: SECURITY INTEREST (SEE DOCUMENT FOR DETAILS).
  • Assignor: MESOBLAST INTERNATIONAL SARL; MESOBLAST LIMITED ACN 109 431 870; MESOBLAST UK LIMITED; MESOBLAST, INC. (FORMERLY KNOWN AS ANGIOBLAST, INC.)
  • Assignee: OAKTREE FUND ADMINISTRATION, LLC
  • Correspondent: JASON C. VOGEL, LATHAM & WATKINS LLP, 330 MADISON AVENUE, NEW YORK, NEW YORK, UNITED STATES 10017.
  • Context: Securitization of intellectual property, likely as collateral for a loan or financing. Oaktree Fund Administration, LLC is an investment adviser firm that provides administrative services for investment companies and pooled vehicles.

• 2026-01-02 (executed) / recorded 2026-01-02 — Reel 066708/0462

  • Conveyance: RELEASE OF SECURITY INTEREST IN INTELLECTUAL PROPERTY
  • Assignor: OAKTREE FUND ADMINISTRATION, LLC, AS AGENT
  • Assignee: MESOBLAST UK LIMITED; MESOBLAST INTERNATIONAL SARL; MESOBLAST LIMITED; MESOBLAST, INC. (FORMERLY KNOWN AS ANGIOBLAST, INC.)
  • Correspondent: CHRISTOPHER GADJO, DENTONS US LLP, P.O. BOX 1339, CHICAGO, ILLINOIS, UNITED STATES 60690-1339.
  • Context: Release of a security interest, indicating the satisfaction of the underlying debt or financing arrangement.

Timeline diagram

timeline
    title Ownership of US 11708560
    2019 : Filed by Mesoblast Intl SARL
    2020 : Inventor rights to Osiris
         : Osiris to Mesoblast Intl SARL
    2021 : Security Interest to Oaktree
    2023 : Issued
    2026 : Security Interest Released

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The assignees, Mesoblast International SARL and Osiris Therapeutics, Inc., are both operating companies involved in cellular and regenerative medicine. Oaktree Fund Administration, LLC is an investment firm, and its involvement was a security interest, not a transfer of ownership for assertion.
2. Known asserter in the chain — Not present. None of the listed assignees or security interest holders (Mesoblast International SARL, Osiris Therapeutics, Inc., Oaktree Fund Administration, LLC) appear on public NPE lists such as RPX or Unified Patents.
3. Repeat correspondent across the chain — Present. Beth M. Goldman of Morrison & Foerster LLP is listed as the correspondent for both assignments on 2020-01-15 (Reel 051000/0839 and Reel 051000/0843). This individual/firm is known to handle patent assignments for various operating companies, suggesting a legal counsel specializing in corporate transactions rather than a specific NPE pattern.
4. Cascading transfers — Not present. While there were two assignments on the same day in 2020, they represent the transfer of inventor rights to a prior assignee (Osiris) and then from that assignee to the current owner (Mesoblast). The security interest and its release are separate financial events.
5. Pre-litigation transfer — Unclear. There is no information in the provided context about any infringement suits related to this patent, so this cannot be determined.
6. Bankruptcy fire-sale — Not present. Osiris Therapeutics, Inc. was acquired by Smith & Nephew in 2019, not dissolved or in bankruptcy. Mesoblast International SARL is an active operating company.
7. Privateering — Not present. There is no evidence suggesting a transfer to an NPE to assert on behalf of an operating company.
8. Defensive aggregator (anti-NPE) — Not present. None of the entities in the chain are defensive aggregators.

Verdict

Operating-company assertion. The patent originates from and is currently held by Mesoblast International SARL, an active biotechnology company that develops and commercializes MSC therapies. The intermediate transfers, including the assignment from Osiris Therapeutics, Inc. (an operating company acquired by Smith & Nephew), and the security interest with Oaktree Fund Administration, LLC, are consistent with normal corporate and financial transactions for an operating company rather than NPE activity. The patent was released from the security interest as of 2026-01-02 (Reel 066708/0462), returning full control to Mesoblast International SARL.

USPTO Assignment Center Search for US11708560

To identify the most relevant prior art for US patent 11708560, I will access the patent information directly from Google Patents, which provides a comprehensive view including cited prior art. The USPTO Public Search tool is also a valid source, but Google Patents often presents the information more readily for analysis.

Prior Art Cited in US11708560B2:

Here's an analysis of the prior art cited in US11708560B2, focusing on relevance to the claims:

1. WO 2007/123363 (Choung et al.)

   • Full Citation: WO 2007/123363 A1 (Choung et al.)
   • Publication/Filing Date: Publication: November 1, 2007. Priority Date: April 27, 2006.
   • Brief Description: This patent application describes an MSC preparation enriched for CD105+ and CD45- cells.
   • Potential Anticipation (35 U.S.C. § 102): The '560 patent explicitly distinguishes itself from Choung et al. by stating that Choung et al. "does not teach an MSC preparation that is pure for CD166+ cells, CD105+ cells, and CD45- cells and does not teach a clinical scale MSC preparation containing a billion MSCs." Therefore, while relevant for general MSC preparations and some markers (CD105+, CD45-), it does not appear to anticipate the specific combination of antigen markers including CD166+, the scale (1 billion MSCs), or other features like TNFR1 expression, immunosuppression by inhibition of IL-2Rα expression, resilience to cryopreservation, and differentiation capacity after passage expansion, as claimed in the '560 patent (e.g., Claim 1, and claims dependent on its features like Claim 16, 17, 18, 19, 20, 21, 22).

2. US 6,251,295 to Johnson

   • Full Citation: US 6,251,295 B1 (Johnson)
   • Publication/Filing Date: Issue: June 26, 2001. Filing: April 21, 1999.
   • Brief Description: This patent describes an apparatus for washing mesenchymal stem cells, specifically mentioning a closed or semi-closed system for processing steps like filling, sampling, and transferring solutions.
   • Potential Anticipation (35 U.S.C. § 102): This patent primarily addresses the method and apparatus for washing cells within a manufacturing process. While the '560 patent mentions the use of such washing apparatus in its manufacturing methods (e.g., within the general methods described in the detailed description for preparing MSCs), it does not claim the washing apparatus or method itself as novel. Therefore, it potentially anticipates aspects of the manufacturing process steps in the '560 patent related to cell washing (as described, for instance, in Example 12 and Example 28), but not the composition of matter (the MSC preparation) or the specific selection criteria for therapeutic use as defined in independent claims such as Claim 1 or Claim 15-22.

3. WO 2007/087139 to Danilkovitch et al.

   • Full Citation: WO 2007/087139 A2 (Danilkovitch et al.)
   • Publication/Filing Date: Publication: August 2, 2007. Priority Date: January 26, 2006.
   • Brief Description: This patent application describes methods for quantifying TNFRI using ELISA assays in mesenchymal stem cell cultures.
   • Potential Anticipation (35 U.S.C. § 102): This reference is relevant to the method of determining TNFRI levels, which is a key characteristic used for selecting MSC preparations in Claim 17 of the '560 patent, and a characteristic described for the preparations in Claim 1. However, it does not disclose the specific MSC preparation itself with the combination of features claimed in '560, particularly the specific antigen profile, cell count, and other functional characteristics. It anticipates the analytical technique for one of the claimed features, rather than the invention's composition or overall therapeutic method.

4. Le Blanc et al. ("Mesenchymal Stem Cells Inhibit the Expression of CD25 (Interleukin-2 Receptor) and CD38 on Phytohaemagglutinin-Activated Lymphocytes", Scandinavian Journal of Immunology, 2004, Vol 60 No 3, Pages 307-315)

   • Full Citation: Le Blanc et al., "Mesenchymal Stem Cells Inhibit the Expression of CD25 (Interleukin-2 Receptor) and CD38 on Phytohaemagglutinin-Activated Lymphocytes", Scandinavian Journal of Immunology, 2004, Vol 60 No 3, Pages 307-315.
   • Publication/Filing Date: 2004
   • Brief Description: This scientific publication describes a method for determining TNFRI activity by measuring the percent IL-2Rα expression inhibition on mitogen-stimulated white blood cells.
   • Potential Anticipation (35 U.S.C. § 102): Similar to WO 2007/087139, this publication provides a method for assessing a functional characteristic (immunosuppression via IL-2Rα inhibition) that is a part of the TNFRI profile and potency definition in the '560 patent, and used as a selection criterion in Claim 17. It does not disclose the specific MSC preparation with the unique combination of features claimed in '560.

5. Wagner et al. ("Replicative Senescence of Mesenchymal Stem Cells: A Continuous and Organized Process", PLoS ONE. 2008; 3(5): e2213; Wagner et al. "How to track cellular aging of mesenchymal stromal cells?," Aging (Albany N.Y.). 2010 April; 2(4): 224-230).

   • Full Citation: Wagner et al., "Replicative Senescence of Mesenchymal Stem Cells: A Continuous and Organized Process", PLoS ONE. 2008; 3(5): e2213; Wagner et al., "How to track cellular aging of mesenchymal stromal cells?," Aging (Albany N.Y.). 2010 April; 2(4): 224-230.
   • Publication/Filing Date: 2008 (PLoS ONE), 2010 (Aging)
   • Brief Description: These publications describe methods for determining senescence in MSCs, including the identification of senescent markers.
   • Potential Anticipation (35 U.S.C. § 102): These references describe methods for determining a "non-senescent state," which is a characteristic of the MSCs in the '560 patent (e.g., discussed in the detailed description, and potentially relevant to Claim 1 in terms of the quality of the MSCs). However, they do not disclose the specific MSC preparation or methods of making it as claimed in '560.

6. Copending application Ser. No. 12/541,282, filed Aug. 14, 2009

   • Full Citation: US Patent Application No. 12/541,282 (now US 8,114,379 B2).
   • Publication/Filing Date: Filing: August 14, 2009.
   • Brief Description: This application describes quantitative assays for determining residual levels of BSA and trypsin.
   • Potential Anticipation (35 U.S.C. § 102): This reference is relevant to the method of screening for BSA and trypsin content, which is a selection criterion in Claim 22 of the '560 patent. It does not disclose the specific MSC preparation itself.

Summary of Anticipation:

The cited prior art primarily describes:

• General MSC characteristics and isolation methods (Choung et al.).
• Methods/apparatus for cell processing during manufacturing (Johnson).
• Assay methods for characterizing MSCs, such as TNFRI quantification, IL-2Rα inhibition, senescence, and residual component detection (Danilkovitch et al., Le Blanc et al., Wagner et al., and US 12/541,282).

None of the cited prior art appears to fully anticipate the core independent Claim 1 of US11708560, which defines an MSC preparation by a specific combination of features: a high cell count (at least 1 billion), a precise antigen profile (less than ~1.25% CD45+, at least ~95% CD105+, and at least ~95% CD166+), and other optional but important characteristics like TNFRI expression, cryopreservation resilience, and differentiation capacity. The prior art provides background and methods for assessing some of these individual features but not the combined novel preparation itself. Similarly, the method claims (Claims 15-22) build upon this specific MSC preparation, making direct anticipation by the cited art unlikely, though elements of the methods of screening and making are certainly informed by the cited analytical techniques.

Obviousness Analysis under 35 U.S.C. § 103

This analysis will assess the obviousness of US patent 11708560's claims, particularly focusing on combinations of prior art references that would render the invention obvious to a Person Having Ordinary Skill in the Art (PHOSITA) at the time of the invention (before the priority date of October 8, 2010).

Definition of a Person Having Ordinary Skill in the Art (PHOSITA)

A PHOSITA is a hypothetical person who is presumed to know all pertinent publicly available prior art at the time of the invention. This individual possesses ordinary skill, ordinary creativity, and ordinary knowledge in the relevant technical field and is expected to think along the lines of conventional wisdom, apply known techniques in a predictable manner, and draw upon the publicly accessible prior art. The PHOSITA is not an inventor or a genius but represents the average skilled practitioner in the field.

For US patent 11708560, which relates to enhanced mesenchymal stem cell (MSC) preparations, methods for their manufacture, screening, and therapeutic uses, the PHOSITA would likely possess at least an undergraduate degree in a relevant biological science field (e.g., cell biology, immunology, biotechnology, biomedical engineering) with several years of experience in cell culture, stem cell isolation, expansion, characterization, and therapeutic applications of MSCs. This PHOSITA would be familiar with standard techniques for culturing and expanding MSCs, characterizing cell surface markers, assessing differentiation capacity, and understanding the challenges associated with large-scale production and cryopreservation of cells for clinical use. They would also be aware of the importance of cell purity, potency, and safety for therapeutic applications.

Obviousness of Claim 1: MSC Preparation with Specific Antigen Profile and Cell Count

Claim 1 describes a preparation comprising at least 1 billion MSCs, characterized by an antigen profile of less than approximately 1.25% CD45+ cells, at least approximately 95% CD105+ cells, and at least approximately 95% CD166+ cells.

Combination of Prior Art: WO 2007/123363 (Choung et al.) and General Knowledge in MSC Culture and Expansion.

WO 2007/123363 (Choung et al.) describes an MSC preparation enriched for CD105+ cells and CD45- cells. While the patent states that Choung et al. does not teach a preparation "pure for CD166+ cells, CD105+ cells, and CD45- cells" or a "clinical scale MSC preparation containing a billion MSCs," it provides a clear starting point for a PHOSITA.

1. Antigen Profile (CD45-, CD105+): Choung et al. explicitly describes enriching for CD105+ and CD45- cells. The isolation and characterization of MSCs using specific surface markers like CD45 (negative marker for hematopoietic cells), CD105, and CD90 (positive markers for MSCs) was well-established in the art prior to 2010. A PHOSITA would understand that enriching for CD105+ and CD45- cells would lead to a population that is largely homogeneous for these markers. Furthermore, the inclusion of CD166+ in the antigen profile would have been an obvious addition to a PHOSITA. CD166 (ALCAM) was also a known marker for MSCs. A PHOSITA, seeking to further define or purify MSC populations, would routinely investigate additional known MSC markers like CD166.
2. Cell Count (at least 1 billion MSCs): The art recognized the challenge of obtaining sufficient quantities of MSCs for clinical applications and discussed methods for large-scale expansion. For instance, US8956862B2, which claims priority to a 2009 application, explicitly discusses methods for "large scale expansion for therapeutic application of bone marrow derived MSCs." Similarly, other prior art discusses "billion-fold expansion of hMSCs" through traditional cell culture techniques, although noting that this could lead to a loss of self-renewal and stem cell properties. Given the known therapeutic potential of MSCs, a PHOSITA would be highly motivated to expand MSCs to clinically relevant numbers (i.e., at least 1 billion cells), using established cell culture techniques such as serial passaging and increasing culture surface area, to meet the demands of therapeutic applications. The goal of achieving large cell numbers was a driving force in MSC research and manufacturing.

Therefore, a PHOSITA, starting with the MSC enrichment described by Choung et al. and applying routine cell culture expansion techniques, in combination with the knowledge of various MSC markers and the clinical need for large cell numbers, would have been motivated to produce an MSC preparation with the specified antigen profile (including CD166+) and a cell count of at least 1 billion.

Obviousness of Claims 15-22: Methods of Treatment and Manufacturing with Additional Profiles

Claims 15-22 introduce further characteristics or selection criteria for the MSC preparations, including TNFRI expression, cryopreservation resilience, differentiation capacity, normal karyotype, pathogen-free status, and low residual levels of BSA/trypsin.

Combination of Prior Art: Choung et al., WO 2007/087139 (Danilkovitch et al.), and General Knowledge in MSC Biology and Clinical Manufacturing.

1. TNFRI Expression and Immunosuppression (Claim 17): US11708560 states that Choung et al. "does not provide teachings of other technical features such as TNFRI expression, immunosuppression by inhibition of IL-2Rα expression." However, WO 2007/087139 (Danilkovitch et al.), specifically mentioned in US11708560 as describing methods for quantifying TNFRI, demonstrates prior art knowledge of TNFRI in the context of MSCs. The role of MSCs in immunosuppression was also recognized in the prior art, with studies investigating their ability to suppress T-cell activation. A PHOSITA familiar with MSC biology and the art of immunosuppression would understand the potential significance of TNFRI expression as a marker for MSC potency. Therefore, combining the general MSC preparation methods with an assay for TNFRI, as described by Danilkovitch et al., to select for potent MSCs would have been obvious to a PHOSITA.
2. Cryopreservation Resilience (Claim 18): The ability to cryopreserve MSCs while maintaining viability is crucial for clinical applications. The challenges and methods for cryopreserving MSCs and assessing post-thaw viability were well-known in the art. Prior art highlights the importance of cryopreservation for shipping and storage of cell products, and studies already evaluated the impact of freezing and thawing on cell viability and phenotype. A PHOSITA would be motivated to select for MSC preparations with high post-thaw viability (e.g., >70%) as a standard quality control measure for clinical products.
3. Differentiation Capacity (Claim 19): One of the defining characteristics of MSCs is their multipotent differentiation capacity into adipogenic, chondrogenic, and osteogenic lineages. This characteristic was routinely assessed as part of MSC characterization. Therefore, selecting for MSC preparations that retain this capacity after expansion would be a predictable step for a PHOSITA aiming to ensure the functional integrity of therapeutic MSCs.
4. Normal Karyotype (Claim 20), Pathogen-Free (Claim 21), and Low Residuals (Claim 22): These aspects relate to the safety and purity of cell preparations for clinical use. Ensuring a normal karyotype, freedom from pathogens, and low levels of manufacturing residuals (like BSA and trypsin) are fundamental requirements for any cell-based therapeutic product. These are standard good manufacturing practice (GMP) considerations and quality control measures. A PHOSITA working in the field of clinical-grade cell manufacturing would inherently incorporate such screening and selection steps to meet regulatory requirements and ensure patient safety. The methods for screening for pathogens (e.g., endotoxin, bacteria, fungi, viruses) and for quantifying residual manufacturing agents were well-established in the prior art.

A PHOSITA, faced with the need to produce safe, potent, and functionally robust MSC preparations for clinical use, would have been motivated to combine the basic MSC isolation and expansion techniques (as outlined by Choung et al. and general knowledge) with these standard characterization, quality control, and safety assessment methods. The individual elements of these claims were known in the art, and their combination would have been a logical and predictable step for a PHOSITA seeking to optimize MSC preparations for therapeutic applications.