How mesenchymal stem cell cotransplantation with hematopoietic stem cells can improve engraftment in animal models

Table 1 Characteristics of hematopoietic stem cells

Ref.	Year	Hematopoietic stem cells			Transplantation
		Donor	Source	Lineage	Cell dose	Route	Volume (µL)
Lee et al[9]	2021	Mice (C57BL/6)	BM	NC	1 × 107	IV	NR
Huang et al[10]	2021	Human	UCB	MNC	1 × 107	IV; IB	200; NR
Yin et al[8]	2020	Human	UCB	CD34+	2.5 × 103; 5 × 103; 1 × 104; 2 × 104	IV; IB	NR; 10
Choi et al[11]	2020	Mice (C57BL/6)	BM	NC	1 × 107	IV	200
Trento et al[12]	2017	Mice (C57BL/6 CD45.1)	BM	NC	2 × 106	IV	NR
Abbuehl et al[13]	2017	Mice (FVB Actin-GFP)	BM	NC	5 × 106	IV	100
Kim et al[14]	2016	Mice (C57BL/6J-Pep3b-Ly5.1 Pep3b)	BM	NC	2 × 104	NR	NR
Futrega et al[15]	2016	Human	UCB	CD34+	5 × 104	IV; IB	100; 10
van der Garde et al[16]	2015	Human	UCB	CD34+	2 × 105	IV	NR
Fernández-García et al[17]	2015	Mice (P3D2F1 H2b/d CD45.1)	BM	LSK	1.5 × 104	NR	NR
Chen et al[18]	2015	Mice (C57BL/6)	BM	NC	5 × 106	IV	NR
Chen et al[19]	2014	Human	UCB	CD34+	1 × 105	IV	NR
Wu et al[20]	2013	Human	UCB	NC	1 × 106	IV	250
Lim et al[21]	2013	Human	UCB	MNC	1 × 107	IV	200
Lee et al[22]	2013	Human	UCB	CD34+	2 × 105	IV	150-200
Kornblit et al[23]	2013	Dog (beagle)	BM	NC	1.8-5.3 × 108/kg	IV	50 mL
Fortin et al[24]	2013	Mice (B6.SJL-PtrcaPep3b/BoyJ CD45.1)	BM	NC	2 × 106	IV	NR
Carrancio et al[25]	2013	Human	UCB	CD34+	1 × 105	IV; IB	200; 20

BM: Bone marrow; MNC: Mononuclear cells; NC: Nucleated cells; UCB: Umbilical cord blood; LSK: Lineage^- Sca-1+ cKit+; IV: Intravenous; IB: Intrabone; NR: Not reported.

Table 2 Characteristics of mesenchymal stem cells

Ref.	Mesenchymal stem cells					Transplantation
	Donor	Source	Surface marker	Passage	Modification	Cell dose	Route	Volume (µL)
Lee et al[9]	Human	Tonsil	Negative: CD14, CD34, CD45, HLA-DR, CD40, CD80, CD86 CD11b, CD21, CD23, CD35 and CD54	P3-5	MMP3-knockdown	1 × 106	IV	NR
			Positive: CD73, CD95 and CD105
Huang et al[10]	Human	UCB	Negative: CD34 and CD45	P4	NA	5 × 106; 1 × 106	IV; IB	NR
			Positive: CD90, CD105 and CD75
Yin et al[8]	Human	UCB	NR	NR	GFP; EGF; FGF2; PDGFB	5 × 105	IB	10
Choi et al[11]	Human	Tonsil	Negative: CD14, CD34, CD45, HLA-DR, CD40, CD80, CD86 CD11b, CD21, CD23, CD35 and CD54	P3-5	NA	2 × 106	IV	200
			Positive: CD73, CD95 and CD105
Trento et al[12]	Mice (C57BL/6 CD45.2 orNos2-/-)	BM	Negative: CD45	Max P8	Nos2-/-	2 × 105	IV	NR
			Positive: PDGFRα and Sca-1
Abbuehl et al[13]	Mice (FVB Insulin-GFP)	BM	Negative: CD105	NR	NA	1 × 104	IB	3
			Positive: CD73 and Sca1
Kim et al[14]	Mice (C57BL/6J-Ly 5.2 BL6)	BM	Negative: CD45	Min P2	NA	2 × 105	NR	NR
Futrega et al[15]	Human	BM	Negative: CD45, CD34 and HLA-DR	P3	NA	5 × 105	IV; IB	100; 10
			Positive: CD44, CD90, CD73, CD105 and CD146
van der Garde et al[16]	Human	FL	Negative: CD34	NR	NA	1 × 106	IV	NR
Fernández-García et al[17]	Mice (B6D2F1, H2b/d, CD45.2)	AT	Negative: CD34, CD45.1 and CD80Low: Sca-1	P5-8	NA	2 × 105; 4 × 105; 6-10 × 105	IV	NR
			Positive: CD29, CD44, CD73, CD90.2, CD105, CD106, CD144, and CD166
Chen et al[18]	Mice (C57BL/6)	BM	NR	P3-8	CXCR4	5 × 105	IV	NR
Chen et al[19]	Human	BM	Negative: CD34 and CD45	NR	SDF1; HOXB4	8 × 105	IV	NR
			Positive: CD90 and CD44
Wu et al[20]	Human	UCB	Negative: CD14, CD31, CD34, CD45, and HLA-DR	NR	NA	1 × 106	IV	250
			Positive: CD13, CD29, CD44, CD73, CD90, and CD105
Lim et al[21]	Human	UCB	Negative: CD14, CD34 and CD45	P4	NA	5 × 106	IV	200
			Positive: CD73 and CD105
Lee et al[22]	Human	UCB; AT; BM	Negative: CD14, CD34, and CD45	NR	NA	1 × 106	IV	150-200
			Positive: CD73, CD90, and CD105
Kornblit et al[23]	Dog (beagle)	BM	NR	P1	NA	4.8-10 × 108/kg	IV	50 mL
Fortin et al[24]	Mice	BM	Negative: CD45 and CD31	NR	solG-CSFR	1.5 × 107	IP	NR
			Positive: CD44 and CD90dim
Carrancio et al[25]	Human	BM	Positive: CD73, CD90, CD105, CD44, and CD166	P3	NA	5 × 105	IV; IB	200; 20

AT: Adipose tissue; FL: Fetal lung; BM: Bone marrow; UCB: Umbilical cord blood; MMP3: Matrix metallopeptidase 3; GFP: Green fluorescent protein; EGF: Epidermic growth factor; FDF2: Fibroblast growth factor 2; PDGFB: Platelet-derived growth factor subunit B; CXCR4: C-X-C chemokine receptor type 4; SDF-1: Stromal cell-derived factor 1; HOXB4: Homeobox B4; solG-CSFR: Soluble granulocyte colony-stimulating factor decoy receptor; TPO: Thrombopoietin; Nos2^-/^-: Deficient in type 2 nitric oxide; IP: Intraperitoneal; IV: Intravenous; IB: Intrabone; NR: Not reported; NA: Not applied.

Table 3 Bone marrow cotransplantation model

Ref.	HSC donor	MSC donor	Host	Conditioning	Source	Dose (Gy)	MSC immunogenicity	Groups
Lee et al[9]	Mice (C57BL/6)	Human	Mice (BALB/c H-2d)	Chemotherapy	Bu/Cy	25 mg/kg/4 d	Xenogeneic	Control; HSC; HSC + T-MSC; HSC + MMP3kdT-MSC
						100 mg/kg/2 d
Huang et al[10]	Human	Human	Mice (NOD/SCID)	TBI	60-Co	2.7	Xenogeneic	Control; HSC; HSC + UCB-MSC (IV/IB)
Yin et al[8]	Human	Human	Mice (NOD/SCID; NOG)	TBI	NR	2.5	Xenogeneic	HSC; HSC + GFP-MSC; HSC + EGF-MSC; HSC + FGF2-MSC; HSC + PDGFB-MSC (IV/IB)
Choi et al[11]	Mice (C57BL/6)	Human	Mice (BALB/c)	Chemotherapy	Bu/Cy	20 mg/kg/4 d	Xenogeneic	Control; HSC; HSC + T-MSC
						100 mg/kg/2 d
Trento et al[12]	Mice (C57BL/6 CD45.1)	Mice (C57BL/6 CD45.2 orNos2-/-)	Mice (C57BL/6 CD45.2)	TBI	NR	8	Allogeneic	HSC; HSC + MSC; HSC + Nos2−/−MSC
Abbuehl et al[13]	Mice (FVB Actin-GFP)	Mice (FVB Insulin-GFP)	Mice (FVB Insulin-GFP)	TBI	NR	2 × 4.5	Allogeneic	HSC; HSC + MSC
Kim et al[14]	Mice (C57BL/6J-Pep3b-Ly5.1 Pep3b)	Mice (C57BL/6J-Ly 5.2 BL6)	Mice (C57BL/6J-Ly 5.2 BL6)	TBI	NR	9	Xenogeneic	HSC; HSC + MSC (NSS/SS) direct or priming
Futrega et al[15]	Human	Human	Mice (NSG)	TBI	137-Cs	2.5	Xenogeneic	HSC (IV/IB); HSC + MSC; HSC + MSC-spheroids (IB)
van der Garde et al[16]	Human	Human	Mice (NOD/SCID)	TBI	NR	3.5	Xenogeneic	HSC; HSC + MSC; Ex/TPO-HSC; Ex/TPO-HSC + MSC
Fernández-García et al[17]	Mice (P3D2F1 H2b/d CD45.1)	Mice (B6D2F1,H2b/d, CD45.2)	Mice (B6D2F CD45.2)	TBI	NR	5-7	Allogeneic	HSC; HSC + AT-MSC
Chen et al[18]	Mice (C57BL/6)	Mice (C57BL/6)	Mice (BALB/c H-2d)	TBI	60-Co	7.5	Allogeneic	HSC; HSC + EGFP-MSC; HSC + CXCR4-MSC
Chen et al[19]	Human	Human	Mice (NOD/SCID/IL2rγnull)	TBI	60-Co	3.5	Xenogeneic	Control; HSC; HSC + MSC; HSC + SDF-1-MSC; HSC + HOXB4-MSC; HSC + SDF1-HOXB4-MSC
Wu et al[20]	Human	Human	Mice (NOD/SCID)	TBI	NR	3.5	Xenogeneic	HSC; HSC + UCB-MSC
Lim et al[21]	Human	Human	Mice (NOD/SCID)	TBI	Cs	2.5	Xenogeneic	HSC; HSC + hPTH; HSC + UCB-MSC + hPTH
Lee et al[22]	Human	Human	Mice (NOD/SCID)	TBI	NR	3	Xenogeneic	HSC; HSC + BM-MSC; HSC + AT-MSC; HSC + UCB-MSC
Kornblit et al[23]	Dog (beagle)	Dog (beagle)	Dog (Beagle)	TBI	60-Co	9.2	Allogeneic	Control; HSC; HSC + MSC (unrelated or DLA-id MSC)
Fortin et al[24]	Mice (B6.SJL-PtrcaPep3b/BoyJ CD45.1)	Mice	Mice (C57BL/6J)	TBI	60-Co	8	Allogeneic	HSC; HSC + MSC; HSC + solG-CSFR-MSC
Carrancio et al[25]	Human	Human	Mice (NOD/SCID)	TBI	Cs	3	Xenogeneic	HSC (IV/IB); HSC IV + MSC (IV/IB)

Bu: Busulfan; Cy: Cyclophosphamide; TBI: Total body irradiation; Cs: Cesium; Co: Cobalt; HSC: Hematopoietic stem cells; Ex/TPO-HSC: HSC expanded with thrombopoietin; MSC: Mesenchymal stem cells; T-MSC: Tonsil mesenchymal stem cells derived; UCB-MSC: Umbilical cord blood mesenchymal stem cells derived; AT-MSC: Adipose tissue mesenchymal stem cells derived; BM-MSC: Bone marrow mesenchymal stem cells derived; MMP3kdT-MSC: Mesenchymal stem cells with matrix metallopeptidase 3-knockdown; GFP-MSC: Mesenchymal stem cells expressing green fluorescent protein; EGF-MSC: Mesenchymal stem cells expressing epidermic growth factor; FGF2-MSC: Mesenchymal stem cells expressing fibroblast growth factor 2; PDGFB-MSC: Mesenchymal stem cells expressing platelet-derived growth factor subunit B; Nos2^-/-MSC: Mesenchymal stem cells deficient in type 2 nitric oxide; EGFP-MSC: Mesenchymal stem cells expressing enhanced green fluorescent protein; CXCR4-MSC: Mesenchymal stem cells expressing C-X-C chemokine receptor type 4; SDF-1-MSC: Mesenchymal stem cells expressing stromal cell-derived factor 1; HOXB4-MSC: Mesenchymal stem cells expressing Homeobox B4; solG-CSFR-MSC: Mesenchymal stem cells expressing soluble granulocyte colony-stimulating factor decoy receptor; hPTH: Human parathyroid hormone; DLA: Dog leukocyte antigen; DLA-id: Dog leukocyte antigen identical; NSS: Non-stimulatory serum; SS: Stimulatory serum.

Table 4 Cotransplantation evaluation

Ref.	Objective	Therapy evaluation	Evaluation technique	Evaluation time (d)	Outcome	Conclusion
Lee et al[9]	Evaluate cotransplantation of HSCs and T-MSCs and influence of MMP3 expression	Chimerism	FC	10	Only the HSC + T-MSC group had a significant increase in frequency of H-2d cells in PB receptor	Cotransplantation of T-MSCs with intact expression of MMP3 increased homing and engraftment of HSCs, as well as blood cell recovery and survival
					The HSC + MMP3kdT-MSC group did not present any alteration
		Hematopoietic reconstitution	BC	24	The HSC + T-MSC group had the highest number of circulating WBCs and RBCs and similar level to the control group
		Homing	FC	1	The groups that received T-MSCs presented higher homing independently of expression of MMP3
		Cellularity	H&E	24	The cellularity of the BM only was significantly increased in the HSC + T-MSC group
		Survival	Kaplan-Meier estimator	24	The HSC + T-MSC group had a higher survival rate (71%) in comparison to the HSC + MMP3kdT-MSC group (38%)
Huang et al[10]	Evaluate the cotransplantation of HSCs and UCB-MSCs in an iron overload model	Chimerism	FC	42	Cotransplantation of HSCs with UCB-MSCs increased the frequency of CD45+ cells in BM, independently of route, and presented a higher frequency of CD34+ only with IB route	Cotransplantation of HSCs with UCB-MSCs increased the engraftment and the proliferation of UCB-MNCs, improving their differentiation in the iron overload model independently of the administration rote
		Distribution	Fluorescence	42	HSCs in the IV group accumulated in the spleen but not BM, and in the IB group, accumulation was mainly in BM
		Expression of hematopoietic cytokines	IHC	42	Cotransplantation of HSCs with UCB-MSCs increased expression of VEGF-A, OPN, and SDF-1 independently of route
		Survival	Kaplan-Meier estimator	42	The HSC + UCB-MSC group via IB had a higher survival rate
Yin et al[8]	Evaluate the cotransplantation of HSC and MSC expressing EGF, FGF2 or PDGFB	Chimerism	FC	84	There was no difference in the frequency of CD34+ and CD45+ between the HSC + MSC and HSC groups	BM treated with PDGFB-MSCs improved the self-renewal of human HSCs in primary recipients, leading to superior engraftment in secondary transplantation
					PDGFB-MSC significantly increased the frequency of CD45+ and CD34+ human cells in comparison with HSC group, except CD34+ IV
					The FGF2-MSC group had a significant increase in CD45+ by IB route compared with the HSC group
					PDGFB-MSC promoted a higher frequency of CD45+ in secondary transplantations
Choi et al[11]	Evaluate the cotransplantation of HSCs and T-MSCs in thymus regeneration	Survival	Kaplan–Meier estimator	40	The HSC + T-MSC group had a higher survival rate	Cotransplantation of HSCs and T-MSCs improved survival rate and restored the thymus structure and increased the diversity of thymus-derived T cells
		Thymus regeneration	Tissue volumetry	3, 10 and 40	In 10 d, the thymuses of the HSC + T-MSC group were larger
					In 40 d, the thymuses of all groups returned to a size similar to the control thymus
			Histology		Highest cellularity and better-defined structures in the HSC + T-MSC group
			IHC		The HSC + T-MSC group presented more CD3+ cells
Trento et al[12]	Evaluate the cotransplantation of HSC and Nos2−/− MSC in the differentiation of myeloid cells	Chimerism	FC	13	There was no difference in the frequency of CD45.1+ myeloid cells in the BM and in the spleen of the recipient animals	There was no difference in the frequency of neutrophils and eosinophil between the groups, macrophages and monocytes were more numerous in the HSC + MSC group
		Hematopoietic reconstitution	FC	13	There was an increase of the frequency of macrophages and monocytes in the HSC + MSC group compared to the HSC and HSC + Nos2−/− MSC group
Abbuehl et al[13]	Evaluate the cotransplantation of HSCs and MSCs	Chimerism	FC	112	Cotransplantation of HSCs and MSCs increased the frequency and number of GFP+ LSK, HSCs (LSK CD48 CD150+) and LT- HSCs (LSK CD48- CD150+ CD34) cells in secondary receptors of HSCs derived from the HSC + MSC group	Cotransplantation of HSCs with MSCs significantly increased number of functional HSCs derived from donors
		Hematopoietic reconstitution	BC	7 and 14	Highest number of lymphocytes and neutrophils in 14 d in the HSC + MSC group
Kim et al[14]	Evaluate the cotransplantation of HSCs and stimulated MSCs	Chimerism	FC	64 to 84	Percentage of CD45.1+ and number of LSK CD45.1 cells increased in the HSC + MSC-SS group	Cotransplantation of HSCs with MSCs under stimulatory condition increased HSC engraftment
					Percentage of CD45.1+ lymphoid cells was equal in the HSC and HSC + MSC-NSS groups, however there was a reduction in the HSC + MSC-SS group IB route, the reverse was observed in myeloid cells
		Hematopoietic reconstitution	IHC	64 to 84	Only observed in the HSC + MSC-SS group
Futrega et al[15]	Evaluate the cotransplantation of HSCs and MSC-spheroids	Chimerism	FC	56 (weekly)	Reduction of CD45+ in the HSC + MSC group in spleen comparing IB to IV route	HSC transplantation by IB route improved IB engraftment, but did not contribute to high levels of systemic engraftment in xenogeneic animal models and cotransplantation with MSC-spheroids enhanced supportive environment to retention of HSC in IB route
					Significant reduction of CD34+ in the MSC-spheroids group in PB and spleen in IB route
					Increase in engraftment of CD45+ and CD34+ in IB administration of the HSCs with MSCs or without MSCs in comparison to distal bone
van der Garde et al[16]	Evaluate the cotransplantation of HSCs expanded with TPO and MSCs	Chimerism	FC	42	The HSC + MSC group had significantly increased CD45+ in the receptors while TPO only induced engraftment	Cotransplantation of MSCs can improve engraftment after 6 wk, whereas TPO expansion improves early platelet recovery
		Platelet recovery	FC	14 and 42	In short term, use of Ex/TPO-HSCs with or without MSCs increased platelet number, in long term, only the presence of MSCs with HSCs had an effect on platelet formation
Fernández-García et al[17]	Evaluate the cotransplantation of HSCs and AT-MSCs	Chimerism	FC	28, 56, and 84	Cotransplantation of HSCs and MSCs resulted in an increase of CD45.1+ in the receptor dose-dependently in the mild conditioning (5 Gy)	Cotransplantation with low doses of AT-MSCs accelerated early HSC engraft, but only higher dose of MSCs improved later HSC engraftment, as also long-term repopulating HSCs, and homing of HSCs, facilitating hematopoietic reconstitution
					Highest frequency of CD45.1+ in secondary and tertiary receptors, using HSCs + higher doses of AT-MSCs
		Homing	FC	2, 4, and 24 h	Co-infusion of AT-MSCs increased homing of LSK CD45.1+ cells in BM
Chen et al[18]	Evaluate the cotransplantation of HSCs and MSCs overexpressing CXCR4	Chimerism	FC	7 and 14	At 7 d, frequency of H-2b cells in the receptors was lower in the HSC + CXCR4-MSC group, increasing equally in all groups at 14 d	Cotransplantation of HSCs with CXCR4-MSCs accelerates hematopoietic reconstitution, promotes HSC engraftment, PB cell recovery, and BM hyperplasia
		Hematopoietic reconstitution	BC	7 to 21	The HSC + MSC group increased reconstitution of leukocytes and platelets, and HSC + CXCR4-MSC group had more rapid effect
		Cellularity	HE	7 and 14	Highest cellularity in the BM and in the spleen of the receptors of CXCR4-MSC, predominantly myeloid in BM
Chen et al[19]	Evaluate the cotransplantation of HSCs and MSCs modified to express SDF-1/HOXB4	Chimerism	FC	28	The presence of CD45+ was higher in the groups that received MSCs, with emphasis in HSC + SDF1-HOXB4-MSC group	HSC + SDF1-HOXB4-MSC group significantly increased engraftment of HSCs, hematopoietic recovery, and rapid recovery of BM cellularity
		Hematopoietic reconstitution	BC	7, 14, 21, and 28	In the HSC + SDF1-HOXB4-MSC group, the WBCs, PLT and HGB levels returned to normal
					The HSC + SDF-1-MSC group did not present total recovery, although the WBC, PLT and HGB levels recovered more quickly than in other groups
		Cellularity	Wright staining	14 and 28	The cellularity was significantly higher in the HSC + SDF-1-MSC and HSC + HOXB4-MSC groups
		Survival	Kaplan–Meier estimator	14 and 28	The HSC + SDF1-HOXB4-MSC group had higher survival rate than other groups
Wu et al[20]	Evaluate the cotransplantation of HSCs and MSCs	Chimerism	FC	56 to 77	The HSC + UCB-MSC group had higher frequency of CD45+ in the PB and BM	The use of UCB-MSCs in cotransplantation resulted in better engraftment of HSCs
Lim et al[21]	Evaluate cotransplantation of HSCs treated with hPTH and MSCs	Hematopoietic reconstitution	BC	28, 42 and 49	There was no difference in the number of WBCs, RBCs and PLTs in the groups over time	Cotransplantation of HSCs with MSCs could lead to an increase of hematopoietic reconstitution and may be a synergistic effect between MSCs and hPTH
		Cellularity	FC	49	There was difference only in the HSC and HSC + UCB-MSC groups treated with hPTH
					CD34+ did not differ between the groups, but myeloid and lymphoid lineages were markedly higher in HSC + UCB-MSC + hPTH group
			HE	56	Highest cellularity of the BM in the groups that received hPTH with or without MSCs
Lee et al[22]	Evaluate the cotransplantation of HSCs and AT-MSCs, UCB-MSCs or BM-MSCs	Chimerism	FC	42 or 70	The groups that received MSCs, independently of the source, had an increase of the frequency of CD45+ cells	Cotransplantation of HSCs with BM-MSCs, AT-MSCs or UCB-MSCs increased engraftment, and UCB-MSCs had higher proliferation rates
Kornblit et al[23]	Evaluate the cotransplantation of HSCs and MSCs with identical DLA or not	Hematopoietic reconstitution	BC	100	There was no difference in the number of PLTs and granulocytes between the groups	Cotransplantation of HSCs with MSCs did not increase engraftment of HSCs, and the MSCs with identical DLA or not was safe
Fortin et al[24]	Evaluate the cotransplantation of HSCs and MSCs expressing solG-CSFR	Chimerism	FC	13 and 45	In the HSC + MSC group, there was a higher number of CD45+ compared to other groups	In the cotransplantation of HSCs with MSCs, the presence of solG-CSFR increased the homing and accelerated hematopoietic reconstitution
		Homing	FC	18 h	The homing was significantly higher in the HSC + solG-CSFR-MSC group than the HSC + MSC group, and in this last group the increase did not differ from the control group
Carrancio et al[25]	Evaluate the cotransplantation of HSCs and MSCs according to the routes (IB and IV)	Chimerism	FC	21 and 42	The number of CD45+ was significantly higher in the HSC + MSC s by IV route (at 21 d), but at 42 d, this increase occurred in the HSC + MSC group by IB route in the local area of administration, followed by the HSC + MSC group by IV	MSCs increased hematopoietic engraftment when cotransplanted by both routes (IV/IB)

HSC: Hematopoietic stem cells; Ex/TPO-HSC: HSC expanded with thrombopoietin; MSC: Mesenchymal stem cells; T-MSC: Tonsil mesenchymal stem cells derived; UCB-MSC: Umbilical cord blood mesenchymal stem cells derived; AT-MSC: Adipose tissue mesenchymal stem cells derived; BM-MSC: Bone marrow mesenchymal stem cells derived; FGF2-MSC: Mesenchymal stem cells expressing FGF-2; PDGFB-MSC: Mesenchymal stem cells expressing PDGFB; Nos2^-/-MSC: Mesenchymal stem cells deficient in type 2 nitric oxide; CXCR4-MSC: Mesenchymal stem cells expressing CXCR4; SDF-1-MSC: Mesenchymal stem cells expressing SDF-1; HOXB4-MSC: Mesenchymal stem cells expressing HOXB4; solG-CSFR-MSC: Mesenchymal stem cells expressing solG-CSFR; MMP3kdT-MSC: Mesenchymal stem cells with matrix MMP3 knockdown; VEGF-A: Vascular endothelial growth factor; OPN: Osteopontin; SDF-1: Stromal cell-derived factor-1a; EGF: Epidermic growth factor; FGF-2: Fibroblast growth factor 2; PDGFB: Platelet-derived growth factor subunit B; GFP: Green fluorescent protein; LSK: Lineage^- Sca-1+ cKit+; NSS: Non-stimulatory serum; SS: Stimulatory serum; TPO: Thrombopoietin; CXCR4: C-X-C chemokine receptor type 4; SDF-1: Stromal cell-derived factor 1; HOXB4: Homeobox B4; hPTH: Human parathyroid hormone; DLA: Dog leukocyte antigen; solG-CSFR: Soluble granulocyte colony-stimulating factor decoy receptor; MMP3: Matrix metallopeptidase 3; FC: Flow citometry; BC: Blood count; H&E: Hematoxylin staining; IHC: Immunohistochemistry; BM: Bone marrow; PB: Peripheral blood; WBC: White blood cells; RBC: Red blood cells; PLT: Platelets; HGB: Hemoglobin; IV: Intravenous; IB: Intrabone.