Epidermal cell thymocyte activity factor/interleukin 1 (ETAF/IL)-like activity in lymph drained from normal human...

Area of Science:

• Immunology
• Dermatology
• Cell Biology

Background:

• Human skin lymph contains lymphocytes with high spontaneous blastic transformation and lectin responsiveness.
• This suggests extravasated subpopulations or lymph-borne co-stimulatory factors.

Purpose of the Study:

• To determine if human prenodal skin lymph possesses lymphokine activity.
• To identify the source of this activity within skin-draining lymph.

Main Methods:

• Assessing lymph's effect on lectin-induced thymocyte and autologous blood lymphocyte proliferation.
• Using anti-interleukin-1 (IL-1) antiserum to abrogate activity.
• Analyzing supernatant from cultured lymph cells (lymphocytes, Langerhans cells).

Main Results:

• Skin lymph significantly augmented lectin-induced lymphocyte proliferation.
• This augmenting activity was neutralized by anti-IL-1 antiserum.
• No IL-1 activity was detected in lymph cell supernatant or serum.
• The source of the activity was identified as epidermal, not mononuclear cells.

Conclusions:

• Human skin lymph contains epidermal cell thymocyte activating factor/interleukin (ETAF/IL)-1-like activity.
• This activity is distinct from serum factors and IL-2.
• The primary source of this lymphokine activity is epidermal cells within the skin.