Elderly subjects suffer from increased levels of activated T cells and a TH1/TH2 imbalance. Zinc deficiency of the aged is correlated with decreased cell-mediated immune responses. The association of age and zinc adjustment with the amounts of TH1 (CCR5+) and TH2 (CCR4+) cell populations in healthy aged old donors enrolled in the European ZINCAGE project was examined. Old and nonagenarian indiv...

Adefovir dipivoxil treatment has significantly improved the outcome of chronic hepatitis B virus (HBV) infection. However, it remains largely unknown how immune system responds to the treatment. Chronic HBV patients were treated with adefovir dipivoxil and examined for serum HBV DNA loads, cytokines, and T helper (Th1) and 2 (Th2) cytokine producing T cells during 104 weeks of the treatment. Th...

T helper cell (Th1 and Th2) associated responses were examined following a primary infection with the gastrointestinal nematode Heligmosomoides polygyrus in five inbred strains of mice with different resistance phenotypes. Levels of (i) mast cell protease, (ii) specific IgE, (iii) nitric oxide and (iv) specific IgG2a, as markers of Th2 and Th1 associated responses, respectively, were determined...

Th1 cells that produce IFN-gamma are essential in the elimination of intracellular pathogens, and Th2 cells that synthetize IL-4 control the eradication of helminths. However, highly polarized Th1 or Th2 responses may be harmful and even lethal. Thus, the development of strategies to selectively down-modulate Th1 or Th2 responses is of therapeutic importance. Herein, we demonstrate that dihydro...

The objective of this study was to compare the concentrations of Th1 (IFN-γ , TNF-α) and Th2 (IL-4,IL-10) cytokines in the serum of normal pregnant and recurrent spontaneous abortion (RSA) women in 1st trimester as well as in the normal fertile non pregnant women. In RSA women there was a significant increasing in the mean concentration of Th1 cytokines (TNFα and IFNγ) as well as in Th1/TH2 tha...

The ability of committed Th1 and Th2 cells to function in altered cytokine environments is a central issue in autoimmune and immune-mediated diseases. Therefore, it is of interest to study the ability of Th1 or Th2 cells to expand and produce cytokine reciprocal environments in vivo. Using STAT4- and STAT6-deficient mice, we studied the expansion and cytokine production of Ag-specific Th1 or Th...

Phosphodiesterase (PDE) inhibitors can modulate the functions of immune cells, including T lymphocytes, due to increased intracellular levels of cyclic nucleotides. The drugs (aminophylline, milrinone and sildenafil) were administered once or five times at 24 h intervals at the following doses: 20 mg/kg, i.m., 1 mg/kg, i.m. and 1 mg/kg, p.o., respectively. Th1 and Th2 cytokine levels (IL-2, IFN...

We present and analyze a model for the cross-regulation of the Th1 and Th2 helper cell subsets during an immune response by the regulatory cytokines interferon-gamma (IFN)-gamma) and interleukin-10 (IL-10). IFN-gamma, secreted by Th1 cells, can inhibit the proliferation of Th2 cells. Interleukin-10, secreted by Th2 cells, inhibits cytokine production by Th1 cells. Based on these properties, the...

helper T lymphocytes (Th) were subdivided into two distinct populations, Th1 and Th2 cells. Th1 cells producing interferon-g (IFN-g) play a critical role in cellular immunity, while Th2 cells producing interleukin (IL)-4 and IL-5 are essential for the regulation of humoral immunity. The balance between Th1and Th2-dominant immunity (Th1/Th2 balance) was thought to be important for the developmen...

Johne's disease (JD), a persistent and slow progressing infection of ruminants such as cows and sheep, is caused by slow replicating bacilli Mycobacterium avium subspecies paratuberculosis (MAP) infecting macrophages in the gut. Infected animals initially mount a cell-mediated CD4 T cell response against MAP which is characterized by the production of interferon gamma (Th1 response). Over time,...