ant ▁home ost asis . ▁Since ▁SP - B ▁has ▁a ▁major ▁role ▁in ▁sur fact ant ▁bi ogen esis ▁and ▁spread ing ▁of ▁sur fact ant ▁and ▁li pid ▁layer , ▁any ▁dis ruption ▁to ▁existence ▁of ▁SP - B ▁results ▁in ▁in effect ive ▁resp iration ▁and ▁le th al ▁pul mon ary ▁conditions ▁at ▁birth . ▁Path ology ▁manifest ation ▁in ▁full - term ▁infant ▁res emb les ▁characteristics ▁of ▁new born ▁with ▁Res p ir atory ▁Dist ress ▁Sy nd rome . ▁Im aging ▁of ▁ep ith el ial ▁type ▁II ▁cells ▁with ▁SP - B ▁def ic iency ▁shows ▁imm ature ▁l am ell ar ▁bodies ▁without ▁tight ly ▁pack ed ▁memb ran es , ▁but ▁rather ▁with ▁loose ▁and ▁un organ ized ▁memb ran es . ▁The ▁ratio ▁of ▁ph osph ol ip id - prote in ▁also ▁decre ases ▁with ▁ab normal ▁ph osph ol ip ids . ▁In ▁addition , ▁sur fact ant ▁collected ▁from ▁SP - B ▁def ic iency ▁ep ith el ial ▁type ▁II ▁cells ▁is ▁not ▁as ▁effective ▁in ▁lower ing ▁surface ▁t ension ▁and ▁creating ▁film ▁as ▁normal ▁sur fact ant . ▁Im mun oh ist och em ical ▁features ▁of ▁SP - B ▁def ic iency ▁show ▁decre ased ▁levels ▁of ▁pro SP - B ▁and ▁SP - B ▁prote ins , ▁along ▁with ▁increased ▁presence ▁of ▁imm uno ▁protein ▁SP - A ▁and ▁partially ▁processed ▁intermediate ▁pe pt ides ▁of ▁pro SP - C . ▁App earance ▁of