Nonhuman primates as models for the discovery and development of radiation countermeasures

Figures & data

Table 1. New World and Old World NHPs.

Features	New World NHPs (Platyrrhines)	Old World NHPs (Catarrhines)
Size	Primates of small to medium size	Primates of medium to large size
Tail	Prehensile (used as 5th limb)	Not prehensile (not used as 5th limb)
Nose	Flat nosed, sideways facing, widely separated nostrils	Narrow nosed, downwards facing, close set nostrils
Dental	12 premolar teeth	8 premolar teeth
Vision	Monochromatic vision with the exception of Howler monkeys	Colored trichromatic vision
Thumbs	Aligned with other fingers; non-opposable	Not aligned with other fingers; opposable
Rump	Lack of padding	Sitting pads present
Habitat	Primarily live in trees	Varied habitat ranging from deserts to rainforests
Pairing	Tend to be monogamous, forming pair bonds and showing paternal care from both parents	Usually less monogamous
Species	Capuchins, Howler monkeys, Marmosets	Rhesus monkeys (Macaca mulatta), Cynomolgus (aka long-tailed or crab-eating) monkeys (Macaca fasicularis), African Green monkeys, Baboons Bonobos, Chimpanzees, Colobus, Gibbons, Gorillas, Guenons, Langurs Leaf monkeys, Macaques, Mangabeys, Orangutans, Patas, Proboscids, Siamangs
	Owl monkeys, Sakis, Spider monkeys, Squirrel monkeys, Tamarins, Titi monkeys, Uakaris, Woollys

Table 2. Some important radiation countermeasures evaluated in NHP models.

Countermeasures	NHPs used	Important attributes	Reference
^aG-CSF (filgrastim, Neupogen)	Rhesus of Chinese origin, Cynomolgus	Enhances survival and blood neutrophil recovery in several species including NHPs regardless of radiation source, requires extensive dosing schedule and full supportive care	[18]
^aPEGylated G-CSF (PEGfilgrastim, Neulasta)	Rhesus of Chinese origin, Cynomolgus	Similar to G-CSF, but it requires few doses (2 doses weekly vs. daily dosing for 17–21 days for G-CSF) without compromising effectiveness	[19]
^bGM-CSF (Leukine, Sargramostim)	Rhesus of Chinese origin	Enhanced survival, blood neutrophil recovery, reduced infection, effective without blood product, and its administration can be delayed till 48 h after irradiation	[20,21]
^bCBLB502 (Entolimod)	Rhesus of Chinese origin	TLR5 ligand stimulating NF-κB that results in inhibition of apoptosis, used as a radioprotector as well as a radiomitigator	[22,23]
^bIL-12 (HemaMax)	Rhesus of Chinese origin	Enhanced survival and promoted hematopoiesis, recovery of immune system and GI functions, single dose administered 24 h post-irradiation increased survival	[24–26]
^b5-AED	Rhesus of Chinese origin	Demonstrated radiomitigation in NHP model, increased survival and stimulated hematopoietic recovery	[27]
γ-tocotrienol (GT3)	Rhesus of Chinese origin	One of the more promising radioprotective tocols, shown to be effective in NHP model by improving hematopoietic recovery following exposure to γ-radiation	[28]
AEOL 10150	Rhesus of Chinese origin	Well-tolerated, spectrum catalytic antioxidant demonstrated to be effective in reducing radiation-induced lung injury and increasing survival in the NHP model, daily doses administered 1–60 d post-irradiation significantly increased survival when compared to control at end of 180 d study	[29,30]
HemokineTM	Baboons (Papio hamadryas Anubis)	Treatment (iv, once daily, twice per wk during the first wk, and five times per wk in the second wk) significantly enhances CFU-GM production, neutrophil recovery, platelet counts, and hematopoietic stem cell survival	[31]
Cytokine combination (FLT3 + Thrombopoietin + IL-3 (SFT3) + PEGfilgrastim)	Cynomolgus	Single administration reduces severity and period of thrombocytopenia with supportive care, administration can be delayed up to 48 h	[32]
Cytokine combination (IL-3 + GM-CSF)	Rhesus; domestic born	Administered twice daily for 21 d post-irradiation, antibiotics were also administered, treatments accelerated platelet and neutrophil recovery	[21]
Stem cell factor + FLT-3 ligand + megakaryocyte growth and development factor + IL-3	Cynomolgus	Single administration with full supportive care stimulated cell recovery and bone marrow hematopoietic activity, 75% of treated NHPs did not experience neutropenia or thrombocytopenia.	[33]
IL-6	Rhesus; domestic born Cynomolgus	Required 2-wk dosing schedule, significant increase in platelets following administration and decreased the need for blood transfusion, administration significantly reduced the duration of thrombocytopenia, also reduced the severity radiation-induced anemia	[34,35]
Recombinant human growth hormone (rhGH)	Cynomolgus	Evaluated against 2 Gy TBI, once daily injections were given for 30 d, rhGH accelerated the recovery of total white blood cells, monocytes, and eosinophils and trended to a faster recovery of neutrophils and lymphocytes compared with saline control	[36]
Cytokine combination (IL-6 + G-CSF)	Cynomolgus	Administration caused significant increases in platelets, neutrophils, and lymphocytes	[34]
Cytokine combination (IL-6 + GM-CSF)	Cynomolgus	Dosing for 21 d demonstrated significant increase in platelets, neutrophils and eosinophils	[34]
Promegapoietin-1α	Rhesus	An agonist for the human IL-3 and Mpl (myeloproliferative leukemia virus oncogene) receptors that stimulates hematopoietic reconstitution, evaluated with full supportive care, significantly improved all platelet-related parameters: thrombocytopenia was eliminated, the severity of platelet nadirs was significantly improved	[37]
Indralin (B-190)	Rhesus	Radioprotective activity of indralin occurs by interaction with α-adrenoreceptor, consistent efficacy over 7 species of animals including NHPs, in a recent study 5 out of 6 NHPs were protected when the drug was administered 5 min before radiation	[38]
IL-1	Cynomolgus	Played important role in hematopoietic regulation, administration of IL-1 to 5 animals shortened post-irradiation neutropenia from 30 to 17 d, as well as increased marrow progenitors, prolonged administration of IL-1 (14 d) was found to be less effective at regulating neutropenia as compared to short treatment courses	[39]
Recombinant glycosylated human IL-6	Baboons	Accelerated peripheral blood platelet count in radiation-induced bone marrow depression	[12]
CD34^+ bone marrow cells	Baboons	Autologous CD34^+ marrow cells completely reconstituted the radiation-induced hematopoietic damage in baboons	[40]
Leridistim	Rhesus	Leridistim or its PEGylated version significantly improved neutrophil recovery following radiation induced myelosuppression.	[41–43]
IL-6 + IL-3	Rhesus; domestic born	Coadministration improves polymorphonuclear cell recovery compared with IL-6 alone and decreases duration of thrombocytopenia. Sequential administration significantly increases platelet production and reduces the duration of thrombocytopenia.	[35]
Megakaryocyte growth and development factor + G-CSF	Rhesus; domestic born	Administration significantly enhanced platelet recovery, reduced duration of thrombocytopenia and neutropenia, and enhanced multilineage hematopoietic recovery.	[44]
Synthokine SC-55494	Rhesus; domestic born	This high-affinity IL-3 receptor ligand significantly reduced the duration of thrombocytopenia. When administered post-TBI, significantly enhanced platelet recovery and modulated neutrophil nadir.	[45]
Synthokine SC-55494 + GM-CSF	Rhesus; domestic born	Significantly shortens the period of neutropenia and improves platelet nadir. Requires twice daily dosing for 23 days following TBI	[46]
Recombinant human G-CSF + TPO + IL-2	Rhesus	When used in combination, significantly promoted hematopoietic recovery and colony formation as well as increased survival (100%) in NHPs exposed to 7.0 Gy ^60Co γ-radiation.	[47]
Recombinant TPO	Rhesus	Single administration of TPO 24 h following 5 Gy TBI prevented thrombocytopenia, accelerated the reconstitution of immature CD34^+ BM cells, and potentiated the response to growth factors in NHPs.	[48]
Myelopoietin	Rhesus	Significantly reduced duration and severity of neutropenia and thrombocytopenia in NHPs treated with MPO when compared control cohorts after exposure to either 7.0 Gy ^60Co γ-radiation or 6.0 Gy 250 kVp X-ray.	[43]
Autologous bone marrow transplantation	Rhesus; domestic-born	Significantly improves the duration and nadir of thrombocytopenia and platelet recovery, requires infusion within 2 h of TBI.	[49]

^aFDA approved for H-ARS.

^bFDA IND.

Large number of radiation countermeasures have been investigated using NHP model. We have presented some of those agents in this table.

Figure 1. Comparison of NHP neutrophils, platelets, WBC, monocytes, and lymphocytes of survivors and non-survivors after exposure to various doses of radiation. NHPs were exposed to ⁶⁰Co γ-irradiation (5.0, 5.8, 6.5, or 7.2 Gy). Blood was collected at various time points post-radiation, and cells were counted using a Bayer Advia-120 cell counter. The data for each time point are shown as the mean ± standard error for those which survived until 60 d (survivors, blue) and those who succumbed to the effects of radiation before 60 d (non-survivors, orange). It should be noted that all animals surived after exposure to 5.0 Gy radiation.

Figure 2. Radiation-induced changes in NHP cytokines. NHPs were exposed to various doses (5.0, 5.8, 6.5, or 7.2 Gy) of ⁶⁰Co γ-irradiation. Blood was collected at various time points post-irradiation, and cytokines were analyzed using Multiplex Luminex. The data for each time point are shown as the mean ± standard error for each radiation group. *indicates the time points when the radiation dose dependent first order correlation were significant and when equal variance between groups were assumed (p ≤ 0.05, n = 8 for 5.8, 6.5, 7.2 irradiated groups and n = 4 for the 5.0 Gy radiation group).

Farese AM, MacVittie TJ. Filgrastim for the treatment of hematopoietic acute radiation syndrome. Drugs Today (Barc). 2015;51:537–548.

 PubMed Web of Science ®Google Scholar

Hankey KG, Farese AM, Blaauw EC, et al. Pegfilgrastim improves survival of lethally irradiated nonhuman primates. Radiat Res. 2015;183:643–655. .

 PubMed Web of Science ®Google Scholar

Clayton NP, Charpentier EJJ, LaCasse ER, et al. Sargramostim significantly improved the mortality rate at Day 60 in a non-human primate model of hematopoietic acute radiation syndrome with minimal supportive care when administered 48 h after total body irradiation. 42nd Conference of the European Radiation Reasearch Society; 2016; Amsterdam, Netherlands; p. 190

 Google Scholar

Farese AM, Williams DE, Seiler FR, et al. Combination protocols of cytokine therapy with interleukin-3 and granulocyte-macrophage colony-stimulating factor in a primate model of radiation-induced marrow aplasia. Blood. 1993;82:3012–3018.

 PubMed Web of Science ®Google Scholar

Krivokrysenko VI, Shakhov AN, Singh VK, et al. Identification of granulocyte colony-stimulating factor and interleukin-6 as candidate biomarkers of CBLB502 efficacy as a medical radiation countermeasure. J Pharmacol Exp Ther. 2012;343:497–508. .

 PubMed Web of Science ®Google Scholar

Krivokrysenko VI, Toshkov IA, Gleiberman AS, et al. The Toll-like receptor 5 agonist Entolimod mitigates lethal acute radiation syndrome in non-human primates. Plos One. 2015;10:e0135388.

 PubMed Web of Science ®Google Scholar

Gluzman-Poltorak Z, Mendonca SR, Vainstein V, et al. Randomized comparison of single dose of recombinant human IL-12 versus placebo for restoration of hematopoiesis and improved survival in rhesus monkeys exposed to lethal radiation. J Hematol Oncol. 2014;7:31.

 PubMed Web of Science ®Google Scholar

Gluzman-Poltorak Z, Vainstein V, Basile LA. Recombinant interleukin-12, but not granulocyte-colony stimulating factor, improves survival in lethally irradiated nonhuman primates in the absence of supportive care: evidence for the development of a frontline radiation medical countermeasure. Am J Hematol. 2014;89:868–873.

 PubMed Web of Science ®Google Scholar

Stickney DR, Dowding C, Authier S, et al. 5-androstenediol improves survival in clinically unsupported rhesus monkeys with radiation-induced myelosuppression. Int Immunopharmacol. 2007;7:500–505. .

 PubMed Web of Science ®Google Scholar

Singh VK, Kulkarni S, Fatanmi OO, et al. Radioprotective efficacy of gamma-tocotrienol in nonhuman primates. Radiat Res. 2016;185:285–298.

 PubMed Web of Science ®Google Scholar

MacVittie TJ, Gibbs A, Farese AM, et al. AEOL 10150 mitigates radiation-induced lung injury in the nonhuman primate: morbidity and mortality are administration schedule-dependent. Radiat Res. 2017;187:298–318.

 PubMed Web of Science ®Google Scholar

Carter CL, Jones JW, Barrow K, et al. A MALDI-MSI approach to the characterization of radiation-induced lung injury and medical countermeasure development. Health Phys. 2015;109:466–478.

 PubMed Web of Science ®Google Scholar

Faller DV, Castaneda SA, Zhou D, et al. An oral HemokineTM, alpha-methylhydrocinnamate, enhances myeloid and neutrophil recovery following irradiation in vivo. Blood Cells Mol Dis. 2017;63:1–8.

 PubMed Web of Science ®Google Scholar

Herodin F, Roy L, Grenier N, et al. Antiapoptotic cytokines in combination with pegfilgrastim soon after irradiation mitigates myelosuppression in nonhuman primates exposed to high irradiation dose. Exp Hematol. 2007;35:1172–1181.

 PubMed Web of Science ®Google Scholar

Drouet M, Mourcin F, Grenier N, et al. Single administration of stem cell factor, FLT-3 ligand, megakaryocyte growth and development factor, and interleukin-3 in combination soon after irradiation prevents nonhuman primates from myelosuppression: long-term follow-up of hematopoiesis. Blood. 2004;103:878–885.

 PubMed Web of Science ®Google Scholar

Zeidler C, Kanz L, Hurkuck F, et al. In vivo effects of interleukin-6 on thrombopoiesis in healthy and irradiated primates. Blood. 1992;80:2740–2745.

 PubMed Web of Science ®Google Scholar

MacVittie TJ, Farese AM, Patchen ML, et al. Therapeutic efficacy of recombinant interleukin-6 (IL-6) alone and combined with recombinant human IL-3 in a nonhuman primate model of high-dose, sublethal radiation-induced marrow aplasia. Blood. 1994;84:2515–2522.

 PubMed Web of Science ®Google Scholar

Chen BJ, Deoliveira D, Spasojevic I, et al. Growth hormone mitigates against lethal irradiation and enhances hematologic and immune recovery in mice and nonhuman primates. PLoS One. 2010;5:e11056.

 PubMed Web of Science ®Google Scholar

Farese AM, Smith WG, Giri JG, et al. Promegapoietin-1a, an engineered chimeric IL-3 and Mpl-L receptor agonist, stimulates hematopoietic recovery in conventional and abbreviated schedules following radiation-induced myelosuppression in nonhuman primates. Stem Cells. 2001;19:329–338.

 PubMed Web of Science ®Google Scholar

Vasin MV, Semenov LF, Suvorov NN, et al. Protective effect and the therapeutic index of indralin in juvenile rhesus monkeys. J Radiat Res. 2014;55:1048–1055.

 PubMed Web of Science ®Google Scholar

Laver J, Abboud M, Gasparetto C, et al. Effects of IL-1 on hematopoietic progenitors after myelosuppressive chemoradiotherapy. Biotherapy. 1989;1:293–300.

 PubMedGoogle Scholar

Herodin F, Mestries JC, Janodet D, et al. Recombinant glycosylated human interleukin-6 accelerates peripheral blood platelet count recovery in radiation-induced bone marrow depression in baboons. Blood. 1992;80:688–695.

 PubMed Web of Science ®Google Scholar

Berenson RJ, Andrews RG, Bensinger WI, et al. Antigen CD34+ marrow cells engraft lethally irradiated baboons. J Clin Invest. 1988;81:951–955.

 PubMed Web of Science ®Google Scholar

Farese AM, Casey DB, Smith WG, et al. Leridistim, a chimeric dual G-CSF and IL-3 receptor agonist, enhances multilineage hematopoietic recovery in a nonhuman primate model of radiation-induced myelosuppression: effect of schedule, dose, and route of administration. Stem Cells. 2001;19:522–533.

 PubMed Web of Science ®Google Scholar

MacVittie TJ, Farese AM, Smith WG, et al. Myelopoietin, an engineered chimeric IL-3 and G-CSF receptor agonist, stimulates multilineage hematopoietic recovery in a nonhuman primate model of radiation-induced myelosuppression. Blood. 2000;95:837–845.

 PubMed Web of Science ®Google Scholar

Farese AM, Hunt P, Grab LB, et al. Combined administration of recombinant human megakaryocyte growth and development factor and granulocyte colony-stimulating factor enhances multilineage hematopoietic reconstitution in nonhuman primates after radiation-induced marrow aplasia. J Clin Invest. 1996;97:2145–2151.

 PubMed Web of Science ®Google Scholar

Farese AM, Herodin F, McKearn JP, et al. Acceleration of hematopoietic reconstitution with a synthetic cytokine (SC-55494) after radiation-induced bone marrow aplasia. Blood. 1996;87:581–591.

 PubMed Web of Science ®Google Scholar

MacVittie TJ, Farese AM, Herodin F, et al. Combination therapy for radiation-induced bone marrow aplasia in nonhuman primates using synthokine SC-55494 and recombinant human granulocyte colony-stimulating factor. Blood. 1996;87:4129–4135.

 PubMed Web of Science ®Google Scholar

Ma YC, Li M, Xing S, et al. [Therapeutic effect of combined cytokines on nonhuman primate model of severe haemopoietic acute radiation sickness]. Zhongguo Shi Yan Xue Ye Xue Za Zhi. 2016;24:573–579.

 PubMedGoogle Scholar

Wagemaker G, Neelis KJ, Hartong SCC, et al. The efficacy of recombinant TPO in murine And nonhuman primate models for myelosuppression and stem cell transplantation. Stem Cells. 1998;16(Suppl 2):127–141.

 PubMedGoogle Scholar

Farese AM, MacVittie TJ, Roskos L, et al. Hematopoietic recovery following autologous bone marrow transplantation in a nonhuman primate: effect of variation in treatment schedule with PEG-rHuMGDF. Stem Cells. 2003;21:79–89.

 PubMed Web of Science ®Google Scholar