Erythropoietin exerts direct immunomodulatory effects on the cytokine production by activated human T-lymphocytes.

The effect of erythropoietin-ß (Epo-ß) on the functional profile of activated human T-lymphocytes remains largely unknown, which hinders clinical application of Epo as an immunomodulatory agent. We studied the direct impact of Epo on the activation status of human T lymphocytes following activation by particles loaded with antibodies (Abs) against human CD2, CD3, and CD28. T cell activation was assessed by the surface expression of CD38 activation marker. Epo did not significantly affect activation status of both CD4(+) and CD4(-) T cells, as well as of naive (CD45RA(+)CD197(+)), central memory (CD45RA(-)CD197(+)), effector memory (CD45RA(-)CD197(-)), and terminally-differentiated (CD45RA(+)CD197(-)) T cells. However, Epo markedly augmented production of IL-2, IL-4 and IL10 by activated T cells with concomitant reduction in IFN-γ secretion. Taken together, our data showed that Epo could directly down-regulate pro-inflammatory T cell responses without affecting T cell activation status.

[DIRECT EFFECT OF IL-7 ON THE GROWTH AND FUNCTIONAL ACTIVITY OF T-LYMPHOCYTES IN THE ABSENCE OF ANTIGENIC STIMULUS].

It is shown that in the absence of antigenic stimulus interleukin-7 (IL-7) is capable of increasing the content of cells expressing the CD25 molecule among both CD4-positive and CD4-negative effector memory T-cells (CD45RA-CD197-), as well as terminally differentiated T cells (CD45RA+CD197-) without causing a significant impact on the status of the activation of naive T cells (CD45RA+CD197+) and central memory T cells (CD45RA-CD197+). IL-7 was also able to enhance T-cell production of IL-2, interferon-γ (IFN-γ) and IL-10, but not IL-4. These data indicate the involvement of IL-7 into a direct upregulation of growth and functional activity of human T cells in the absence of antigenic stimulus and the relative scarcity of costimulatory effects.

[Karyological investigations of populations of the lizard Zootoca vivipara (Juaquin, 1787) from the Baltic Sea basin (western region of Russia)].

Populations of the lizard Zootoca vivipara (Juaquin, 1787) (Lacertidae, Sauria) from Western and Central Europe are poorly differentiated in morphology. However, they differ from each other by several karyotype markers and their reproductive mode (oviparous and viviparous types). Here we report for the first time the results of combined investigations of Z. vivipara from Eastern Europe (the Baltic Sea basin of Western Russia). The karyotype and reproductive mode of the specimens from four previously not examined populations in Kaliningrad region have been studied. It has been shown that these lizards have viviparous mode of reproduction and their karyotypes vary on morphology of W-sex chromosomes. Females possess 2n = 35 : 32 A + Z1Z2W, with W--SV and 2n = 35 : 32 A + Z1Z2W, with W--A/ST. We have identified these populations karyologically and have first revealed that they belong to two different viviparous forms of nominative subspecies Z. v. vivipara, namely to its "western" and "Russian (eastern)" forms. These data have confirmed that the Baltic Sea basin in Eastern Europe is a zone of secondary contact of these chromosomal forms of Z. v. vivipara. The results obtained do not now allow us to speak about their sympatry, parapatry and (or) hybridization events. The results suggest that during postglasial time "western" form might colonize this region from western Europe whereas "Russian (eastern)" form might do it from Southern-Eastern Europe. It has been recommended to save the biodiversity of Z. vivipara in Kaliningrad region, namely the peripheral and very rare on vast territory of Russia "western" form and unique for western region of Russia "Russian (eastern)" form.