Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Multicenter Study
. 2009 Dec;158(3):294-9.
doi: 10.1111/j.1365-2249.2009.04019.x. Epub 2009 Sep 2.

Lower numbers of circulating Natural Killer T (NK T) cells in individuals with human T lymphotropic virus type 1 (HTLV-1) associated neurological disease

L C Ndhlovu  1 , J E Snyder-Cappione, K I Carvalho, F E Leal, C P Loo, F R Bruno, A R Jha, D Devita, A M Hasenkrug, H M R Barbosa, A C Segurado, D F Nixon, E L Murphy, E G Kallas
Affiliations
Multicenter Study

Lower numbers of circulating Natural Killer T (NK T) cells in individuals with human T lymphotropic virus type 1 (HTLV-1) associated neurological disease

L C Ndhlovu et al. Clin Exp Immunol. 2009 Dec.

Abstract

Human T lymphotropic virus type 1 (HTLV-1) infects 10-20 million people worldwide. The majority of infected individuals are asymptomatic; however, approximately 3% develop the debilitating neurological disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). There is also currently no cure, vaccine or effective therapy for HTLV-1 infection, and the mechanisms for progression to HAM/TSP remain unclear. NK T cells are an immunoregulatory T cell subset whose frequencies and effector functions are associated critically with immunity against infectious diseases. We hypothesized that NK T cells are associated with HAM/TSP progression. We measured NK T cell frequencies and absolute numbers in individuals with HAM/TSP infection from two cohorts on two continents: São Paulo, Brazil and San Francisco, CA, USA, and found significantly lower levels when compared with healthy subjects and/or asymptomatic carriers. Also, the circulating NK T cell compartment in HAM/TSP subjects is comprised of significantly more CD4(+) and fewer CD8(+) cells than healthy controls. These findings suggest that lower numbers of circulating NK T cells and enrichment of the CD4(+) NK T subset are associated with HTLV-1 disease progression.

PubMed Disclaimer

Figures

Fig. 2
Fig. 2
Proportion of natural killer T (NK T) cells in patients and controls. The NK T cell frequencies of three subject groups is shown from the American cohort (a) (black dots) and Brazilian cohort (b) (white dots). Absolute numbers of NK T cells for the American cohort (c) (black dots) and Brazilian cohort (d) (white dots).
Fig. 1
Fig. 1
Gating strategy for the natural killer T (NK T) cells. Gating strategy for NK T cells from the (a) San Francisco HTLV Outcomes Study (HOST) cohort and (b) Sao Paulo cohort. One representative donor from each cohort is shown.
Fig. 3
Fig. 3
Proportion of natural killer T (NK T) cell subsets in patients. The frequencies of total (a) NK T cell lymphocyte subsets and (b) CD3+ cells expressing single positive (SP) CD4 and CD8 cells together with CD4-/CD8- double negative (DN) cells from the Brazilian cohort. (c,d) The frequency of NK T cells from two time-points in 10 human T lymphotropic virus type 1 (HTLV-1) infected individuals; HTLV-1 carriers (c) and those with HAM/TSP (d) from the Brazilian cohort. *P < 0·05 statistically significant.
See this image and copyright information in PMC

References

    1. Orland JR, Engstrom J, Fridey J, et al. Prevalence and clinical features of HTLV neurologic disease in the HTLV Outcomes study. Neurology. 2003;61:1588–94. - PubMed
    1. Osame M, Usuku K, Izumo S, et al. HTLV-I associated myelopathy, a new clinical entity. Lancet. 1986;1:1031–2. - PubMed
    1. Gessain A, Barin F, Vernant JC, et al. Antibodies to human T-lymphotropic virus type-I in patients with tropical spastic paraparesis. Lancet. 1985;2:407–10. - PubMed
    1. Itoyama Y, Minato S, Kira J, et al. Spontaneous proliferation of peripheral blood lymphocytes increased in patients with HTLV-I-associated myelopathy. Neurology. 1988;38:1302–7. - PubMed
    1. Bangham CR. Human T-cell leukaemia virus type I and neurological disease. Curr Opin Neurobiol. 1993;3:773–8. - PubMed

Publication types