Scientific Discoveries

photo: Color enhanced image of a cell.

The Tulane National Primate Research Center has been involved in a variety of important multidisciplinary projects focusing on areas of biomedical research with high priority concerns for human health. The information below highlights some of these scientific discoveries.

Origins of AIDS

  • Proved that SIV was an ancient virus much older than originally believed
  • Identified the sooty mangabey as the natural host of SIV and the most likely source of Human Immunodeficiency Virus-2 (HIV-2).
  • Identified a novel SIV in red-capped mangabeys and mandrills.

AIDS Pathogenesis

  • Demonstrated the intestinal immune system is the primary target of SIV infection which was later validated in humans.
  • Defined the early time course and key target cells of SIV infection, which was also validated in HIV-infected humans.
  • Developed the macaque model of neurologic AIDS.
  • Demonstrated that neuroinvasion by SIV occurs within days of infection and involves specific leukocyte and endothelial adhesion molecules and chemokines.
  • Described the early targets and effects of SIV infection on immune cells and responses in the gut, spleen, bone marrow, brain, liver, and thymus in vivo.

Heterosexual Transmission of AIDS

  • Developed the macaque model of heterosexual transmission of SIV.
  • Defined hormonal influences on vaginal transmission of SIV, and first demonstrated progesterone increases SIV/HIV vaginal transmission rates.
  • Demonstrated the protective effects of topical vaginal microbicides to prevent heterosexual transmission of AIDS
  • Identified the first cellular and molecular targets involved in both vaginal and rectal SIV/SHIV transmission

AIDS Vaccines

  • Developed novel mucosal vaccine protocols and approaches.
  • Tested new vaccine candidates and adjuvants in infant and adult macaques


photo: microscopic image of tb.
  • Established various model of TB in rhesus monkeys to study active TB, chemotherapy and response to vaccination, as well as to study TB latency, reactivation by various factors including SIV co-infection, and the impact of ART and LTBI chemotherapy.
  • Developed a new experimental vaccine which shows exceptional promise as a novel anti-TB vaccine vehicle.
  • Established various model of TB in rhesus monkeys to study active TB, chemotherapy and response to vaccination, as well as to study TB latency, reactivation by various factors including SIV co-infection, and the impact of ART and LTBI chemotherapy.
  • Developed a new research area in the field of host-directed therapies against TB, including testing anti-cancer compound Imatinib, which is now included in an NIH-funded clinical trial in South Africa.
  • Developed a new approach to testing the effectiveness of LTBI chemotherapy in the macaque model.
  • Identified a major role for hypoxia response program of M. tuberculosis in persistence in lung granulomas.
  • Identified a major role for B cells in protection from TB.

Lyme Disease Pathogenesis and Spirochete Biology

  • Established the rhesus monkey model of Lyme disease.
  • Discovered that neuronal degeneration secondary to inflammation could cause the mononeuropathy multiplex commonly observed in neuroborreliosis of the peripheral nervous system.
  • Discovered that inflammation is the key effector of Lyme disease in the central nervous system.
  • Discovered an immune evasion mechanism that Borrelia burgdorferi, the spirochete that causes the disease, may use to cause persistent infections.
  • Discovered that spirochetes elicit not only inflammatory but also anti-inflammatory cytokines from monocytes, thus contributing a method to control the inflammation they themselves cause.
  • Discovered that B. burgdorferi regulates gene expression in a cell-density dependent manner.
  • Discovered that B. burgdorferi antigenic variation does not occur in the tick.

Lyme Disease Diagnosis and Treatment

  • Developed a peptide-based diagnostic immunoassay (C6) that outperforms the currently available two-tier test. This assay is now approved by the Food and Drug Administration (FDA) for use in humans and by the USDA for use in animals.
  • Discovered the antigen-dependent dynamics of longitudinal antibody responses to B. burgdorferi infection in monkeys; used these findings to select a combination of antigens for diagnostic test development.
  • Developed a Luminex®-based multi-antigen diagnostic test for serodiagnosis of Lyme disease. This test expands the specificity of detection across early and late phases of disease.
  • Discovered that current antibiotic monotherapy does not clear B. burgdorferi from infected primates. Further study revealed that the persistent spirochetes are living and induce mild to moderate inflammation in multiple organs, including the heart, joints and peripheral nervous system.

Relapsing Fever

  • Established a rhesus macaque model of tick-borne relapsing fever using infection with Borrelia turicatae. Using real-time monitoring, quantified febrile episodes corresponding to high spirochete loads in the blood and discovered that cardiac function is impaired.
  • Discovered inflammatory mediators of blood cells induced specifically by B. turicatae and antibody responses to conserved antigens that may serve as vaccine candidates.


photo: close up image of a mosquito.
  • Discovered the parasite stage responsible for malaria relapse (the hypnozoite).
  • Developed molecular markers for malaria relapse.
  • Developed the first monkey model of malaria during pregnancy.
  • Developed the only successful model of congenital malaria.
  • Established that placental malaria in the macaque is similar to human placental malaria.
  • Ultrasonographic exams established intrauterine growth retardation (IUGR) and not prematurity as the cause of low birth weight (potential model of IUGR).


  • Identified for the first time a prokaryotic gene in a eukaryotic organism, the microsporidian Vittaforma corneae. This led to the inclusion of fluoroquinolones as lead compounds for treating microsporidiosis.
  • Isolated and identified a new microsporidian species, Encephalitozoon hellem, which infects humans and birds.
  • Identified unique genotype markers among isolates of Encephalitozoon cuniculi.
  • Developed improved Polymerase Chain Reaction (PCR)-based methods for diagnosing microsporidiosis.
  • Developed in vitro and in vivo models for testing and identifying drugs with antimicrosporidial activity.
  • Applied genotyping diagnostics to identify animal reservoirs of microsporidia species that pose a risk for transmission to humans.
  • Contributed to genome sequencing and transcriptome projects for several microsporidia species that infect humans, nonhuman primates (and other animals).
  • Defined mechanisms of macrophage-mediated destruction of intracellular microsporidia species that infect humans and nonhuman primates.

Regenerative Medicine

  • Characterized and applied as therapies mesenchymal stem cells from bone marrow and adipose tissue of rhesus macaques.
  • Developed and tested novel CAR-T cell strategies targeting SIV.
  • Started a tissue engineering research program focused on the nonhuman primate model.
  • Successfully developed a tissue engineered nipple areolar complex in the NHP model.
  • Developing novel neurotropic adeno-associated virus vectors via virus evolution for gene therapy applications.
  • Developed novel gene therapy vectors targeting both the brain and hematopoietic stem cells for the treatment of Krabbe’s disease.

Assisted Reproductive Technology

  • Developed a system for the in vitro production of rhesus embryos.
    • Superovulation and retrieval of mature rhesus oocytes.
    • Developed rhesus embryos to the blastocyst stage following in vitro fertilization and culture.
    • Cryopreserved in vitro-derived rhesus embryos.
    • Successfully transferred fresh and cryopreserved normal rhesus embryos resulting in five single and two sets of twin pregnancies.

Celiac Disease

  • Established non-human primate model of celiac disease characterized by:
    • Intestinal tissue transglutaminase and anti-gliadin antibodies.
    • Intestinal inflammatory cytokines, i.e., IFN-gamma and IL-15.
    • Small intestinal enteropathy, villous atrophy and enterocyte apoptosis.
    • Small intestinal intra-epithelial lymphocytosis.
    • Gut microbiome dysbiosis.
    • Upregulation of specific miRNAs with dysbiotic bacteria-binding motifs.
    • Decreased metabolism of xenobiotics, cancer predisposition.
    • MHC II (Mamu II) genetic predisposition.
    • Validated new celiac therapy based on novel breeds of cereal grains.

Enteric Viruses

  • Isolated and characterized a new rotavirus from juvenile monkeys (TUCH):
    • TUCH classified as simian rotavirus, genotype G1P[8].
    • Identified rotavirus VP6-specific CD4+ T cell epitopes.
    • Reported role of rotavirus VP4 in biliary atresia and cholangiopathy.
    • Reported rotavirus interspecies transmission and reassortment.
  • Isolated and characterized a new enteric calicivirus of rhesus origin (TV):
    • New genus within family Caliciviridae, i.e., Recovirus.
    • Recovered infectious TV from transfected cells in vitro.
    • Established juvenile rhesus macaque model of TV infection.
    • Demonstrated presence of TV antibodies in humans.
    • Described genetic diversity and human HBGA-TV interactions.

Congenital Cytomegalovirus (CMV) Infection

  • Developed the first experimental nonhuman primate model of primary congenital CMV infection in rhesus macaques for studies on immune protection and CMV vaccine development
  • First demonstration of placental rhesus CMV transmission in pregnant macaques
  • Demonstrated that maternal CD4+ T lymphocytes are critical for preventing placental CMV transmission and protecting against fetal loss
  • Showed that delayed onset of anti-CMV neutralizing antibodies and CMV-specific T cell immunity increased risk of congenital CMV transmission
  • Demonstrated that passively infused pre-existing high titer anti-CMV antibodies are sufficient for protection against congenital CMV infection
  • Showed evidence of immune selection pressure on transmitted viral variants

The TNPRC is a division of Tulane University (985) 871-6201