Some examples of intracellular pathogens include viruses, the food poisoning bacterium Salmonella and the eukaryotic parasites that cause malaria (Plasmodium spp.) and leishmaniasis (Leishmania spp.). Other bacteria, such as Mycobacterium tuberculosis, live inside a protective capsule that prevents lysis by complement. Many pathogens secrete compounds that diminish or misdirect the hosts immune response. Some bacteria form biofilms to protect themselves from the cells and proteins of the immune system. Such biofilms are present in many successful infections, such as the chronic Pseudomonas aeruginosa and Burkholderia cenocepacia infections characteristic of cystic fibrosis. Other bacteria generate surface proteins that bind to antibodies, rendering them ineffective; examples include Streptococcus (protein G), Staphylococcus aureus (protein A), and Peptostreptococcus magnus (protein L).The mechanisms used to evade the adaptive immune system are more complicated. The simplest approach is to rapidly change non-essential epitopes (amino acids and/or sugars) on the surface of the pathogen, while keeping essential epitopes concealed. This is called antigenic variation. An example is HIV, which mutates rapidly, so the proteins on its viral envelope that are essential for entry into its host target cell are constantly changing. These frequent changes in antigens may explain the failures of vaccines directed at this virus. The parasite Trypanosoma brucei uses a similar strategy, constantly switching one type of surface protein for another, allowing it to stay one step ahead of the antibody response. Masking antigens with host molecules is another common strategy for avoiding detection by the immune system.
Tongue-tie, tongue tied or tongue-tied can refer to:

ankyloglossia, a medical condition in which the lingual frenulum (a membrane that connects the tongue to the floor of the mouth) is unusually short, causing restricted movement of the tongue.Other uses include:

Literature
Tongue-Tied, a 1997 novel by Liselotte Marshall
Tongue-Tied (short story collection), a 2002 collection of short stories by Paul Jennings
"Tongue-Tied" a short story included in the collection
Tongue-Tied: How a Tiny String Under the Tongue Impacts Nursing, Speech, Feeding, and More, a 2018 non-fiction book by Dr. Richard Baxter

Music
Tongue Tied (Red Dwarf song), a song by Danny John-Jules in character as the Cat which was featured in the Red Dwarf episode "Parallel Universe" in 1988
"Tongue Tied" (Boom Crash Opera song), 1995
"Tongue-Tied", a song by Earshot from their 2004 album Two
"Tongue Tied" (Eve 6 song), a single from their 1998 album, Eve 6
"Tongue Tied" (Faber Drive song), 2007
"Tongue Tied" (Grouplove song), 2011
"Tongue Tied" (Marshmello, Yungblud and Blackbear song), 2019
"Tongue Tied", a song by Status Quo from their 2007 album In Search of the Fourth Chord

Other uses
Tongue-tie (tack), a piece of equipment sometimes used on racehorses
"Tongue-Tied" (Orange Is the New Black), a 2015 television episode
Miley Cyrus: Tongue Tied, a 2014 short film starring Miley Cyrus