Effect of panel reactive antibodies on T cell immunity reinstatement following renal transplantation

BACKGROUND

Chronic kidney disease is associated with immunological disorders, presented as phenotypic alterations of T lymphocytes. These changes are expected to be restored after a successful renal transplantation; however, additional parameters may contribute to this process.

AIM

To evaluate the impact of positive panel reactive antibodies (PRAs) on the restoration of T cell phenotype, after renal transplantation.

METHODS

CD4CD28null, CD8CD28null, natural killer cells (NKs), and regulatory T cells (Tregs) were estimated by flow cytometry at T0, T3, and T6 which were the time of transplantation, and 3- and 6-mo follow-up, respectively. Changes were estimated regarding the presence or absence of PRAs.

RESULTS

Patients were classified in two groups: PRA(-) (n = 43) and PRA(+) (n = 28) groups. Lymphocyte and their subtypes were similar between the two groups at T0, whereas their percentage was increased at T3 in PRA(-) compared to PRA(+) [23 (10.9-47.9) vs 16.4 (7.5-36.8 μ/L, respectively; P = 0.03]. Lymphocyte changes in PRA(-) patients included a significant increase in CD4 cells (P < 0.0001), CD8 cells (P < 0.0001), and Tregs (P < 0.0001), and a reduction of NKs (P < 0.0001). PRA(+) patients showed an increase in CD4 (P = 0.008) and CD8 (P = 0.0001), and a reduction in NKs (P = 0.07). CD4CD28null and CD8CD28null cells, although initially reduced in both groups, were stabilized thereafter.

CONCLUSION

Our study described important differences in the immune response between PRA(+) and PRA(-) patients with changes in lymphocytes and lymphocyte subpopulations. PRA(+) patients seemed to have a worse immune profile after 6 mo follow-up, regardless of renal function.

Histomorphometrical and proliferative aspects of placenta and uterus of the collared peccary (Tayassu tajacu)

The histomorphometric and proliferative characteristics of the collared peccary (Tayassu tajacu) placenta and uterus were analyzed. The material was examined by standard histological techniques and histochemistry (PAS, Perls and Alcian Blue pH 0.5 and 2.5%) and the cellular proliferation by AgNORs and flow cytometry. All the analyzed morphometric variables differed between pregnant and non-pregnant uteri in the luteal phase using the Dunnet test. Height and gland diameter of uterine glands increased linearly during pregnancy, with an intense positive PAS and Perls reaction in all stages. The cells with more than seven AgNORs per nuclei and the cells in the G2M cell cycle phase in the maternal tissue also increased after 70 days of pregnancy. The uteroplacental ridges had a linear increase in size with two distinct areas, base and top, with uterine epithelium and trophoblastic cells changing their morphology following the placental ridge development. Flow cytometry analysis showed the percentage of cells in each cell cycle phase with a quadratic behavior for stages G2/M in the maternal tissue, suggesting an increase in proliferative capacity of maternal tissue after 65 days of pregnancy. The same quadratic effect was observed in the G0/G1 phase in both maternal and fetal tissues. Cells in apoptosis showed cubic behavior in both tissues. The morphometric and cellular dynamic aspects observed in this study have not been previously described and they extend our knowledge of functions relating to maternal-fetal dynamics in this species.