MICR - Quiz 3 (Lectures 12-15)

IL-_ starts clonal expansion of naïve T-cells (begins their activation and proliferation)

• IL-2
• IL-4
• IL-10
• IL-7

In B cell signalling, CD40 must occur for a B cell to bind to a T cell. (a)   is present on the T cell and ​ (b)   is present on the B – this signal helps B cells in their (c)   and proliferation. (d)   , a cytokine, is also needed for proliferation and (e)   of B cells.

• CD40L
• survival
• IL-21
• differentiation
• CD40
• IL-2
• IL-17
• IFN-gamma

A) _____, an immunomodulatory molecule that CANNOT be inactivated by S1P lyase blocks the S1P receptor on a lymphocyte from recognizing S1P gradient, whereas _____ inhibits the T-cell from leaving the lymph node by downregulating the expression of S1PR1, the receptor itself

B) Most lymphocytes exist in B & T cell zones within ____ pump

• FTY720, CD69, white

• CD69, FTY720, white

• FTY720, CD69, red

• CD69, FTY720, red

Answer explanation

White pulp is where lymphocytes exist!

Which of the following are chemokines that form the gradient that mediates firm binding in recruiting lymphocytes to secondary lymphoid organs (e.g., lymph node)?

• CD34

• CCL21

• CCL19

• CCR7

• GlyCAM-1

Answer explanation

T cells are deposted into lymph nodes by ___ and leave through _______

Answer explanation

Which of the following are present on the endothelial surface during slow rolling that bind to selectins (during the process of recruiting lymphocytes to secondary lymphoid organs)?

• CD34

• CCL21

• ICAM-1

• GlyCAM-1

• CCR7

Answer explanation

Which of the following is the chemokine receptor present on the lymphocyte itself that responds to the gradient that mediates firm binding in recruiting lymphocytes to secondary lymphoid organs (e.g., lymph node)?

• CD34

• CCL21

• CCL19

• CCR7

• GlyCAM-1

Answer explanation

A) True or false? A BCR heavy chain expresses both allelic exclusion and isotypic exclusion

B) The difference between a T1 and T2 transitional B cell, is that there is the complement receptor CD21 present on __

• True, T1 transitional B cell

• True, T2 transitional B cell

• False, T1 transitional B cell

• False, T2 transitional B cell

Answer explanation

A BCR light chain expresses both allelic exclusion and isotypic exclusion due to the presence of kappa or lambda chains.

A heavy chain only expresses allelic exclusion (does not express isotypic exclusion)

A) Replacement of an autoreactive BCR through ______ is limited to immunoglobulin _____ chain only!

B) If a T1 transitional B cell does not receive the survival signal _____, which is provided by ______ cells, it dies

Answer explanation

Match the binding partners that help guide naïve T cell migration into secondary lymph nodes

• CD43 on an HEV

• LFA-1; present on naive T cell

• MadCAM-1 on MALT endothelium; rolling

• L selectin; present on naive T cell

• MadCAM-1 on MALT endothelium; arrest

• LPAM-1 on naive T cells

• ICAM-1 present on HEV in arrest

• L selectin; present on naive T cell

Answer explanation

PAM is MAd - arrest her!

Also LFA is an integrin present on a T cell - these bind to ITAMs in full arrest on HEVs.

Selectins are involved in rolling alone.