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Topic:Bone Marrow

Bone marrow in horses is a spongy tissue found within the cavities of certain bones, such as the pelvis, ribs, and femur. It is a vital component of the hematopoietic system, responsible for the production of blood cells, including red blood cells, white blood cells, and platelets. These cells are crucial for oxygen transport, immune function, and blood clotting, respectively. Bone marrow consists of two types: red marrow, which is actively involved in blood cell production, and yellow marrow, which primarily stores fat. The composition and activity of bone marrow can change with age, health status, and physiological demands. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and clinical implications of bone marrow in equine health and disease.
Comments on ‘Finite element modelling for investigating bone-implant interactions in equine orthopaedics’.
Equine veterinary journal    June 21, 2026   doi: 10.1002/evj.70221
de Souza AF, Meira JBC, Fonteque JH, De Zoppa ALDV.No abstract available
Circulating Elements in the Bloodstream of Growing Foals: Focus on Heavy Metals and Bone Remodeling Across Growth Stages.
Biological trace element research    June 19, 2026   doi: 10.1007/s12011-026-05186-3
Hulitká D, Coradduzza D, Sanna A, Biggio GP, Taras A, Cannas A, Carru C, Medici S, Cherchi R, Cappai MG.Bone tissue undergoes continuous remodelling throughout the life of the individual, and growth is the most impacting phase. In fact, tightly coordinated processes of resorption, synthesis, and mineralization of the bone matrix under systemic hormonal, biomechanical, and metabolic control occur for variable periods of time across species. The horse is a fast-growing animal and for this reason identified as precocial. It was hypothesized that blood serum levels of minerals in growing foals at different stages of accretion may vary over time. This investigation aimed to assess the dynamics of cir...
Gross and Histopathologic Comparison of the Distal Third Metacarpal Bone and the Proximal First Phalanx with Sodium Fluoride Positron Emission Tomography Radiopharmaceutical Uptake in Five Horses.
Veterinary sciences    June 18, 2026   Volume 13, Issue 6 591 doi: 10.3390/vetsci13060591
Kelleher M, Marr J, Graham B, Cecere T, Klamer B, Anishchenko S, Beylin D.Injuries of the metacarpophalangeal joint are a major cause of morbidity and catastrophic fracture in racing horses, yet early osseous pathology is often difficult to detect using conventional imaging. This pilot study aimed to correlate sodium fluoride Positron Emission Tomography (F-NaF PET) radiopharmaceutical uptake with gross and histopathologic changes in the distal third metacarpal bone (MC3) and proximal first phalanx (P1). Five horses (three racing Thoroughbreds with fetlock injury and two non-racing controls) underwent ante-mortem F-NaF PET and cone-beam CT imaging (CBCT), followed b...
Vital bone and increased osteoid in equine osteochondrosis dissecans of the proximal phalanx: A controlled study indicating a mineralization deficit rather than vascular failure.
Bone    June 12, 2026   Volume 211 117977 doi: 10.1016/j.bone.2026.117977
Leuffert SI, von Brackel FN, Cardinaux EM, Alimy AR, Windels O, Geburek F, Amling M.Osteochondrosis and osteochondrosis dissecans (OCD) are among the most common orthopaedic disorders in young horses. Although traditionally explained by vascular failure and ischaemic necrosis, recent findings in human juvenile OCD suggest that impaired bone mineralization may play an important role. Horses are known to have relatively low circulating vitamin D metabolites, raising the question of whether insufficient mineralization contributes to equine OCD. This study investigated the bone vitality and mineralization status of osteochondrosis dissecans fragments (OCDFs) collected from the do...
Validation of measurable radiographic parameters for quantitative assessment of carpal and metacarpal bone morphology in foals.
Veterinary journal (London, England : 1997)    June 5, 2026   Volume 318 106736 doi: 10.1016/j.tvjl.2026.106736
Son JK, De Paz P, Kim J, Sanaei R, Ryu S, Bailey S, Davies HMS.Radiographic morphometry provides a quantitative means to evaluate bone conformation in horses, yet validation of these parameters in foals has not previously been undertaken. This study aimed to determine the intra- and inter-rater repeatability and reproducibility of established carpal and third metacarpal (MC3) radiographic parameters in Thoroughbred foals and to establish baseline conformational data. Twenty Thoroughbred foals were radiographed without sedation from birth to 14 months of age at two-month intervals. Dorsopalmar carpal and lateromedial MC3 radiographs were obtained using sta...
Visceral disseminated hemangiosarcoma causing severe bicytopenia in a mare.
Journal of equine veterinary science    May 22, 2026   105944 doi: 10.1016/j.jevs.2026.105944
Novotny L, Plachy J, Kveton M, Misik J, Wilkerson MJ.Hemangiosarcoma is an uncommon but highly aggressive malignant vascular neoplasm in horses, most often identified as a disseminated process at postmortem examination. This report describes an adult Warmblood mare presenting with acute hemorrhagic diarrhea, severe anemia, and thrombocytopenia associated with disseminated hemangiosarcoma likely originating in the transverse colon with metastasis to the liver and lungs. This case highlights gastrointestinal hemangiosarcoma as a potential differential diagnosis in horses with unexplained bicytopenia and hemorrhagic enteropathy.
A novel flowable calcium silicate cement for endodontic therapy in equine teeth.
Equine veterinary journal    May 7, 2026   doi: 10.1002/evj.70176
Jackson K, Quintrell E, Staszyk C, Ha W, Kelty E, Patalwala D, Bogen G.Equine endodontic treatment for apical infections is performed infrequently due to anatomical and accessibility challenges of equine cheek teeth. However, the alternative of extraction is not without risk and lifelong implications for the horse. Mineral trioxide aggregate (MTA), a calcium silicate cement (CSC), has been used successfully in human dentistry for decades. MTA and other CSCs demonstrate excellent biocompatibility with favourable antimicrobial and physicochemical properties. These characteristics may support their application as an alternative filling material when used in equine e...
The Effects of Boron Mineral on Performance, Bone and Mineral Metabolism in Purebred Arabian Foals.
Biological trace element research    May 6, 2026   doi: 10.1007/s12011-026-05138-x
Yilmaz İÇ, Güler T, Ekmen EG, Özçelik M.Boron plays significant roles in various biological systems, including mineral, lipid, and energy metabolism, immune and endocrine systems, and brain function. It has been suggested to enhance performance and may prevent conditions such as osteoporosis, osteoarthritis, and arthritis. Despite these known benefits, its effects on growth performance and mineral metabolism in horses remain understudied, particularly in young animals like Purebred Arabian foals. The primary objective of this study was to investigate the effects of different doses of boron supplementation (0, 5, 10, and 15 mg/day ...
Successful Use of Vincristine in a Quarter Horse Gelding with Immune-Mediated Thrombocytopenia.
Journal of equine veterinary science    April 8, 2026   105889 doi: 10.1016/j.jevs.2026.105889
Salewski KE, Talavera MA, Gonzalez GA, Waldridge BM, White JM, Williams MJ, Williams ML.This case reports the successful use of vincristine in a Quarter Horse with presumed immune-mediated thrombocytopenia. A 15-year-old Quarter Horse gelding presented for a pinch skin graft procedure on the left forelimb over the cannon bone. On day 10 of hospitalization, the horse developed a fever (102.6°F, RI: 99-101°F), and severe petechiae of the mucous membranes. A complete blood count (CBC) (Advia 2120i) revealed a severe thrombocytopenia (16,000 platelets/μL, RI:100,000-400,000/μL). Diagnostic testing was negative for Anaplasma phagocytophilum by PCR, Theileria equi and Babesia cabal...
Longitudinal associations between dorsal carpal and third metacarpal bone morphology in Thoroughbred foals during growth.
Journal of equine veterinary science    April 8, 2026   Volume 162 105890 doi: 10.1016/j.jevs.2026.105890
Son JK, De Paz P, Kim J, Sanaei R, Ryu S, Bailey S, Davies HMS.The carpal and third metacarpal (MC3) bones of the equine forelimb undergo morphological adaptation during early growth, influenced by developmental and mechanical factors. However, the longitudinal interactions between dorsal carpal morphology and MC3 structural characteristics have not been fully characterized. Improved understanding of these relationships may help identify morphological indicators associated with bone injury risk before training. Objective: To examine the longitudinal associations between dorsal carpal angular morphology and MC3 diaphyseal parameters in growing Thoroughbred...
Serum-free medium modulates the immunomodulatory and anabolic function of equine bone marrow-derived mesenchymal stromal cells.
Experimental cell research    March 25, 2026   Volume 459, Issue 1 115000 doi: 10.1016/j.yexcr.2026.115000
Tehrani AH, Toth K, Osinchuk N, Dufour A, Krawetz R, Sen A, Sparks H.Adult bone marrow-derived mesenchymal stromal cells (BM-MSCs) hold significant therapeutic potential in human and veterinary medicine. Traditionally, BM-MSC cultures use fetal bovine serum (FBS) to promote growth, but this practice introduces batch variability and xenogeneic contamination that complicate clinical translation. While serum-free medium (SFM) alternatives have been optimized for human MSCs, limited options have been explored for alternative or veterinary species. Here, we compared a chemically defined, customizable SFM formulation with conventional serum-containing medium (SCM) fo...
Ultrasound-guided intralesional tendon and ligament injections in the horse.
Journal of the American Veterinary Medical Association    March 20, 2026   1-2 doi: 10.2460/javma.25.12.0786
Pigé C, Vaughan B, Reesink HL.To describe principles of ultrasound-guided injection techniques for intralesional delivery of regenerative orthobiologics into equine tendon and ligament core lesions. Unassigned: A university-owned horse and equine cadaver forelimbs. Unassigned: A reproducible protocol for ultrasound-guided injection is demonstrated with the superficial digital flexor tendon used as an example. Following diagnosis of the lesion, the horse should be sedated and the affected limb desensitized with perineural anesthesia. The lesion is identified ultrasonographically in transverse and longitudinal planes, marked...
Objective, Longitudinal Computed Tomographic Evaluation of the Metacarpal Condyles in Non-Lame Thoroughbred Racehorses.
Animals : an open access journal from MDPI    March 20, 2026   Volume 16, Issue 6 973 doi: 10.3390/ani16060973
Putnoki V, Pollard D, Dyson S, Boros K, Nagy A.There are limited data on sequential computed tomographic (CT) evaluation and objective CT assessment of the metacarpal condyles in Thoroughbred racehorses. This longitudinal study aimed to document changes in attenuation of the metacarpal condyles during the first two years of training and racing. Fan-beam CT examination of the metacarpophalangeal regions was performed on 40 non-lame Thoroughbred yearlings, and repeated four more times, approximately six months apart. Mean Hounsfield Unit (HU) measurements were obtained on sagittal reconstructions of the dorsal and palmar halves of the medial...
Clinical and research applications of synthetic bone substitutes in equine veterinary medicine: A systematic review.
Equine veterinary journal    February 24, 2026   doi: 10.1002/evj.70151
Skierbiszewska K, Turek B, Jasiński T, Kaczorowski M, Kozłowska N, Higuchi J, Domino M.Bone grafting in equine medicine offers a promising contribution to treating orthopaedic developmental diseases and chondral, osteochondral and segmental bone defects. Among grafts, synthetic bone substitutes-alloplastics-show favourable biological properties addressing numerous limitations presented by autografts, xenografts and allografts. Objective: To compile and disseminate clinical data and research findings from existing publications on the use of alloplastics in horses. Methods: Systematic review. Methods: Following Preferred Reporting Items for Systematic Reviews and Meta-analysis 202...
Bilateral hindlimb superficial digital flexor tendinopathy in a sports horse.
Journal of equine veterinary science    February 20, 2026   Volume 159 105819 doi: 10.1016/j.jevs.2026.105819
Mazzucco L, Marcatili M, Withers J, Cantatore F.Superficial digital flexor tendinopathy is a common cause of forelimb lameness in Thoroughbred racehorses and sports horses; however, this condition is rarely observed in the hindlimb. A 16-year-old Irish sports horse gelding was presented with bilateral swelling in the plantar metatarsal region and severe bilateral hindlimb lameness visible at the walk. The lameness occurred after the cross-country phase of an eventing competition. The clinical suspicion of superficial digital flexor tendon (SDFT) injury was confirmed after ultrasonographic examination, which revealed an extensive core lesion...
Markers of bone turnover, parathyroid hormone, calcium, and magnesium concentrations in horses with acute colitis.
Veterinary journal (London, England : 1997)    February 16, 2026   Volume 316 106595 doi: 10.1016/j.tvjl.2026.106595
Kamr A, Fortin-Trahan R, Arroyo LG, Hostnik LD, Gomez DE, Toribio RE.Hypocalcemia is frequent in horses with colitis. Information on serum parathyroid hormone (PTH) concentrations and its association with bone turnover biomarkers in horses with colitis is lacking. We aimed to determine the association between serum bone resorption biomarkers (C-terminal telopeptide of type I collagen [CTX-I]) and bone formation (osteocalcin [OCN]) with blood PTH, total calcium (tCa), ionized calcium (iCa), phosphorus (Pi), and total magnesium (tMg) concentrations, and mortality in horses with acute colitis. A total of 163 horses were divided into colitis (n = 127) and healt...
Generation and characterization of an immortalized equine osteoblast cell line.
Veterinary journal (London, England : 1997)    January 30, 2026   Volume 316 106573 doi: 10.1016/j.tvjl.2026.106573
Palomino Lago E, Roberts SJ, Orriss IR, Lumsden ES, Guest DJ.Bone is a dynamic tissue that is maintained through the co-ordination of bone resorption and bone formation. An imbalance of these processes can lead to bone disease. In vitro studies of osteoblasts can help to understand bone formation, but primary cells have a limited lifespan in culture. Herein, we report the successful generation of equine immortalized osteoblasts through the stable overexpression of human telomerase reverse transcriptase (hTERT) and Simian virus 40 (SV40) large T-antigen in osteoblasts isolated from trabecular bone taken from the third metacarpal of a two-year-old Thoroug...
Three-dimensional anatomical description of the microarchitecture of the distal sesamoid bone in healthy and navicular syndrome-affected horses by computed microtomography.
Anatomical record (Hoboken, N.J. : 2007)    January 20, 2026   doi: 10.1002/ar.70143
Salinas P, Vergara MA, Tapia D.Navicular syndrome (NS) is a chronic, degenerative condition of the equine thoracic limb that compromises the distal sesamoid bone (DSB) and associated structures responsible for stabilization and load absorption during locomotion. Although historically attributed to vascular alterations, its etiology is now recognized as biomechanical, characterized by chronic overload of the deep digital flexor tendon. Conventional diagnostic techniques-radiography, scintigraphy, and ultrasonography-lack the sensitivity and precision required to detect early microarchitectural alterations. This study aimed t...
Risk assessment for condylar stress fracture in elite racing Thoroughbreds using standing computed tomography-based virtual mechanical testing.
Equine veterinary journal    January 18, 2026   Volume 58, Issue 3 674-681 doi: 10.1002/evj.70145
Brown NL, Irandoust S, Thom EJ, Whitton RC, Henak CR, Muir P.Condylar stress fracture of the third metacarpal bone (MC3) is a common catastrophic injury in Thoroughbred racehorses and is associated with parasagittal groove (PSG) subchondral osteolysis. Standing computed tomography (sCT) imaging enables sensitive identification of this fatigue-induced early subchondral bone injury (SBI), but there is no objective method for identifying racehorses at heightened risk of condylar stress fracture. Objective: To estimate PSG first principal strain in elite Thoroughbred racehorses that have undergone subjective risk assessment using sCT fetlock screening. Meth...
Comparative biomechanical analysis of equine accessory carpal bone fracture repair: Cortical screws in lag fashion versus X-plate technique.
Veterinary surgery : VS    December 21, 2025   Volume 55, Issue 3 620-630 doi: 10.1111/vsu.70071
Gernhardt J, Reuter T, Mählmann K, Schulze N, Lischer CJ.To compare the feasibility and biomechanical stability of two surgical techniques for fixation of vertical plane fractures of the accessory carpal bone (ACB). Methods: Randomized experimental ex vivo study. Methods: Eight equine accessory carpal bones were included in a control group. A total of 20 equine cadaveric forelimbs were randomly assigned into two groups (n = 10 per group). Methods: Vertical plane fractures were created palmar to the extensor sulcus using an oscillating saw. In Group 1 (CS), fractures were stabilized with two 4.5 mm cortical screws in lag fashion. In Group 2 (XP...
Subchondral and Osteochondral Unit Bone Damage in the Fetlock Region of Sport Horses Using Low-Field MRI: Case Series.
Animals : an open access journal from MDPI    December 2, 2025   Volume 15, Issue 23 3468 doi: 10.3390/ani15233468
De Zani D, Rabbogliatti V, Rabba S, Auletta L, Longo M, Zani DD.Damage to the osteochondral unit is a common cause of lameness in horses. Published descriptions of MRI findings of osteochondral unit and subchondral damage are currently lacking, and only a few reports describe outcomes in sport horses. The aims of this case series retrospective study were to describe different MRI patterns of osteochondral/subchondral pathology in the fetlock joint using low-field MRI and to provide outcome information. A total of 35 sport horses were included. Data regarding detailed clinical history, treatment and outcome were evaluated. MRI identified a total of 39 bone ...
Localisation and outcome of presumed thoracolumbar vertebral stress fracture in 35 UK Thoroughbred racehorses using nuclear scintigraphy.
Equine veterinary journal    December 1, 2025   doi: 10.1111/evj.70113
Chapple AR, Daglish J, Stover SM, Slipchenko N, Phillips KL.Stress fracture is an important cause of mortality and morbidity in racing Thoroughbreds. Nuclear scintigraphy is the imaging modality of choice for investigating unlocalised stress-related bone remodelling in horses. Stress fractures of the caudal lumbar vertebral column have been previously described in both racing Quarter horses and racing Thoroughbreds post-mortem. There is a lack of literature describing the imaging appearance of vertebral stress fractures in racehorses ante-mortem. Objective: To describe: (1) ante-mortem scintigraphic appearance of presumed thoracolumbar vertebral stress...
The impact of cumulative bone fatigue on musculoskeletal injury risk in racing Thoroughbreds.
Veterinary journal (London, England : 1997)    November 19, 2025   Volume 314 106502 doi: 10.1016/j.tvjl.2025.106502
Morrice-West AV, Wong ASM, Hitchens PL, Whitton RC.Musculoskeletal injuries (MSI) in racehorses are not typically spontaneous events, but develop gradually through cumulative cycles of loading over time. Stride characteristics can now be recorded with wearable technology, providing opportunity to quantify the skeletal impact of galloping over time. We estimated bone fatigue accumulation based on speed (m/s) and number of strides from n = 3168 race starts by n = 405 Thoroughbreds commencing racing in Tasmania, Australia between 2011 and 2016. The percentage bone fatigue accumulated was divided by various time periods (career, active car...
New Model of Disuse-Induced Bone Density Loss in Horses.
Animals : an open access journal from MDPI    October 29, 2025   Volume 15, Issue 21 3137 doi: 10.3390/ani15213137
Micheau L, Audigié F, Moiroud C, Jacquet S.Disuse-induced bone loss during stall confinement and immobilization is a major concern in horses because it impairs recovery and increases susceptibility to further injury. Experimental models are needed to evaluate therapeutic options, but most available equine models rely on cast immobilization, which is technically demanding and may be associated with complications. This study aimed to assess a simpler and less restrictive model to induce a quantifiable decrease in bone density in horses. Six French Standardbred horses underwent eight weeks of stall confinement, with a wooden wedge fitted ...
Cellular interactions and gene expression analysis of two equine-derived bone graft materials: an in vitro study.
Minerva dental and oral science    October 28, 2025   Volume 74, Issue 6 355-371 doi: 10.23736/S2724-6329.25.05209-X
DI Stefano DA, Coccoluto L, Panina-Bordignon P, Brambilla E, Ruffini F, Murtaj V, Orlando F, Colombo M, Frigerio C, DI Bona A, Recupero D, Morroni M....Bone grafting is a surgical procedure that involves the use of bone tissue or bone substitutes to repair damaged bone. In dentistry and maxillofacial surgery, bone graft substitutes from various sources are commonly used. Given their critical role in clinical outcomes, it is essential to thoroughly investigate the biological and mechanical properties of these materials. Methods: In this in vitro study, we evaluated the biological properties of two equine-derived bone graft substitutes in comparison to β-tricalcium phosphate. The materials included one equine-derived graft containing hydrolyze...
Stress-related bone injuries of the carpal joints in show jumping horses rarely limit long-term performance: a retrospective study of 15 cases.
Journal of the American Veterinary Medical Association    October 24, 2025   Volume 264, Issue 2 218-226 doi: 10.2460/javma.25.07.0443
Micheau L, Jacquet-Guibon S, Tallaj A, Bertoni L, Denoix JM, Coudry V.To describe the type and distribution of carpal joint lesions causing lameness in show jumping horses and describe their 1-year performance outcomes. Unassigned: 15 show jumping horses (median age, 9 years; IQR, 8 to 11 years) of 3 different breeds, mostly Selle Français, evaluated at a referral center between 2013 and 2023. The inclusion criterion was forelimb lameness localized to the carpus, confirmed by perineural or IA analgesia and/or increased radiopharmaceutical uptake on scintigraphy. Horses with limb conformation abnormalities, a history of trauma, or extra-articular soft tissue les...
Use of preoperative computed tomography (CT) to plan repair of comminuted fractures of the middle phalanx in six Warmblood horses: Configuration, treatment and long-term outcome.
Veterinary surgery : VS    October 15, 2025   Volume 54, Issue 8 1698-1710 doi: 10.1111/vsu.70039
Marcatili M, Kalinovskiy A, Christoph L.To describe the additional information provided by computed tomography (CT) in planning and assisting repair of comminuted fractures of the middle phalanx (MP) in Warmblood horses. Methods: Case series. Methods: Six adult Warmblood horses. Methods: The case records of horses undergoing CT examination prior to internal fixation of comminuted MP fractures were reviewed. All horses underwent radiographic and preoperative CT examination. A standardized fast protocol (SFP) to assess CT images was used. Surgical repair consisted of fracture repair and proximal interphalangeal joint arthrodesis using...
A mathematical model of metacarpal subchondral bone adaptation, microdamage and repair in racehorses.
Journal of the Royal Society, Interface    October 1, 2025   Volume 22, Issue 231 20250297 doi: 10.1098/rsif.2025.0297
Pan M, Malekipour F, Pivonka P, Morrice-West AV, Flegg JA, Whitton RC, Hitchens PL.Fractures of the distal limb in Thoroughbred racehorses primarily occur because of accumulation of bone microdamage from high-intensity training. Mathematical models of subchondral bone adaptation of the third metacarpal lateral condyles are capable of approximating existing data for Thoroughbred racehorses in training or at rest. To improve upon previous models, we added a dynamic resorption rate and microdamage accumulation and repair processes. Our ordinary differential equation model simulates the coupled processes of bone adaptation and microdamage accumulation, and is calibrated to data ...
Feasibility and safety of intrathecal transplantation of allogeneic bone marrow mesenchymal stem cells in horses.
Veterinary research communications    September 29, 2025   Volume 49, Issue 6 333 doi: 10.1007/s11259-025-10920-8
de Oliveira Ferreira LV, Maia L, Barberini DJ, Takahira RK, de Vasconcelos Machado VM, Machado GF, de Melo GD, Amorim RM.Mesenchymal stem cells (MSCs) have emerged as a promising alternative for treating neurological disorders due to their neuroprotective, neuroregenerative, immunomodulatory, anti-inflammatory, and anti-apoptotic properties. The use of allogeneic MSCs offers advantages such as the selection of specific cells and their immediate availability. This study aimed to evaluate the safety and feasibility of intrathecal transplantation of allogeneic equine bone marrow-derived MSCs (EqBM-MSCs) in healthy horses. Ten healthy horses (five-12 years old) were randomly divided into two groups. In the control g...
Xenogen-free media provide variable equine mesenchymal stromal cell expansion after a 7-day culture period.
American journal of veterinary research    September 24, 2025   Volume 86, Issue 12 ajvr.25.03.0109.xml doi: 10.2460/ajvr.25.03.0109
Larson MK, Gaffney C, Hoagland C, Jayawickrama J, Kamm JL.To determine the xenogen-free serum source that provides the greatest number of live equine mesenchymal stromal cells (MSCs) while maintaining the MSC phenotype. Unassigned: Equine bone marrow-derived MSCs from 8 horses were cultured for 7 days in media containing one of the following serum treatments: 10% xenogeneic serum, 10% or 20% commercial allogeneic equine serum, 10% autologous serum, 10% equine pooled platelet lysate (PPL), or a staged media reduction of xenogeneic media. Live cell numbers, MSC viability, and MSC immunophenotype were compared. Unassigned: The use of 10% commercial allo...
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