Immunology and Serology Flashcards
7 cards from real Medical Laboratory Technician Exam practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Immunology and Serology flashcards as text
Which complement pathway is activated by mannose-binding lectin (MBL) binding to microbial carbohydrates?
Answer: Lectin pathway
MBL activates the lectin (MBL) pathway by binding mannose residues on microbial surfaces, triggering MASP-1 and MASP-2.
A patient's serum shows a prozone phenomenon in an RPR test. What should the laboratory do?
Answer: Dilute the serum and repeat the test
Prozone occurs with antibody excess; diluting the serum allows lattice formation and produces a visible agglutination reaction.
Which cell type is the primary producer of IgE antibodies in allergic responses?
Answer: Plasma cells derived from B lymphocytes
IgE is secreted by plasma cells (terminally differentiated B cells) after class-switching driven by IL-4 and IL-13.
In a direct antiglobulin test (DAT), a positive result with anti-IgG but negative with anti-C3d most likely indicates:
Answer: Warm autoimmune hemolytic anemia
Warm AIHA is predominantly IgG-mediated without complement deposition, yielding a positive anti-IgG DAT only.
Which cytokine is the primary inducer of acute-phase protein synthesis in the liver?
Answer: IL-6
IL-6 is the principal cytokine that stimulates hepatocytes to produce acute-phase proteins such as CRP and fibrinogen.
A VDRL test performed on CSF is used to diagnose which condition?
Answer: Neurosyphilis
VDRL on CSF is the standard serologic test for diagnosing neurosyphilis, as it has high specificity in that specimen type.
HLA typing is most critical before which clinical procedure?
Answer: Solid organ transplantation
HLA matching between donor and recipient is essential in solid organ transplantation to minimize rejection risk.