Recovery of T‐lymphocytes for adoptive immunotherapy by lymphapheresis of HIV‐infected patients without alterations of virological, immunological or clinical parameters

Abstract

We performed repeated continuous flow cytaphereses (CFC) on 13 asymptomatic HIV-1-infected patients to study the feasibility of cell separation procedures to recover high yields of peripheral blood T-lymphocytes for adoptive immunotherapy in HIV-infected patients and to determine immunological and virological alterations following such procedures. A mean yield of 6.23 x 10(9) lymphocytes could be obtained by each cytapheresis, containing 1.82 x 10(9) CD4+, 3.23 x 10(9) CD8+ T-lymphocytes and 8.39 x 10(6) CD34+ peripheral progenitor cells. The CD4/CD8 ratio (mean 0.53, SD +/- 0.15) in the cell samples reflected the distribution of the lymphocyte subsets in vivo. Absolute lymphocyte counts decreased at a mean of 404/mm3 (25%) immediately after CFC but were replaced from the extravascular pool within 1 h. The CD4/CD8 ratios, p24-antigenaemia, HLA-DR expression and neopterin levels did not change significantly after cell separation. No alteration of the number of T-cells with integrated proviral DNA copies (1/10(3) to 1/10(6)) could be detected in peripheral T-helper cells by PCR after lymphapheresis. We conclude that high yields of peripheral T-lymphocytes can be obtained by continuous flow lymphapheresis for cell-mediated immunotherapy, without deterioration of virological or immunological parameters in HIV-infected patients. The separated T-cells are fully replaced from extravascular pools after 1 h.

The Beneficial Effects of Lymphocytapheresis for Treatment of Nephrotic Syndrome

“…Clinical improvement in patients with rheumatoid arthritis was accompanied by a reduction of T cells, predominantly CD4‐positive T cells, in the synovial membrane (21). In these cases, the CD4/8 ratio of circulating T cells decreased; however, this ratio did not change as a whole in our study as previously noted in human immunodeficiency virus infected cases (22). Because lymphocyte removal was nonselective in our procedure, the change in the CD4/8 ratio may result from differences in lymphocyte kinetics of the disease backgrounds and concomitant drug therapy (15).…”

Changes in immunological and virological parameters in HIV‐1 infected subjects following leukapheresis

“…Both absolute and percentage of CD8 + cell counts returned to pre-leukapheresis values on day 7. These results are in accordance with those reported previously by other investigators [7,8].…”

“…Using an ultrasensitive PCR assay to quantify HIV-1 RNA, we did not observe any increase in viral load in either treated or untreated participants. These results extend those previously reported where P24 antigen was used to monitor viral burden [7,8]. Moreover, in three subjects leukapheresis induces a decrease in viral load shortly after the end of the collection.…”

“…Limited information has been re-ported on the impact of leukapheresis on immunological and virological parameters in HIV-1 infected subjects without prior conditioning with growth factors. Previous studies on leukapheresis in HIV-1 infected subjects have shown that this procedure looks safe without significant changes in CD4 + cell counts or viral load [7,8]. However, these studies did not include untreated HIV-1 infected subjects and viral burden was monitored using serum P24 antigen, which is known to be a less sensitive marker than HIV-1 RNA quantitative polymerase chain reaction (PCR) assay.…”