text: Yo, check it out, I got a story to tell
  'Bout a disease, it's called visceral leishmaniasis, oh, hell
  It's chronic, it's fatal, it's a real tough fight
  With them low-affinity antibodies, it's a dangerous plight
  
  See, in humans, hypergammaglobulinemia is the sign
  That disease progression is comin' down the line
  But what about them hypermutated and class-switched ones?
  Nobody ever studied 'em, we're breakin' new grounds, son
  
  We used Aicda mice, yeah, they were our crew
  And the model of Leishmania donovani, it's true
  Showed that without them mutated antibodies in the mix
  Resistance to disease increased, we got our fix
  
  Stronger Th1 responses, protectin' the host
  Lower frequency of regulatory cells, boastin' the most
  But here's the twist, it's a real mind-bender
  The absence of IFN-gamma and IL-10, it's a game-changer
  
  In them Aicda mice, it wasn't 'cause of T-cell effect
  Nah, it was the cytokine environment, we had to inspect
  TNF, IL-10, IFN-gamma came into play
  Only when them hypermutated antibodies had their say
  
  So, listen up, our results are clear as day
  Hypergammaglobulinemia keeps the inhibitory responses at bay
  During chronic visceral leishmaniasis, it's the key
  Now you know the science, my rap's set you free